0001558370-22-003302 | 10-K | XBRL Viewer

Print Document View Excel Document

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents	$ 137,703	$ 209,520
Accounts receivable - related party	22,384	38,479
Prepaid expenses	8,102	7,082
Tax incentive receivable	12,634	12,930
Other current assets	2,420	4,565
Total Current Assets	183,243	272,576
Property, plant and equipment, net	75,860	44,042
Intangible assets, net	1,791	2,119
In-process research and development	783	852
Other assets	1,404	1,026
Equity method and other investments	6,656
Right-of-use assets - operating leases, net	22,782	21,486
Right-of-use assets - finance leases, net	27,645	21,596
TOTAL ASSETS	320,164	363,697
CURRENT LIABILITIES:
Accounts payable	15,348	7,134
Accrued expenses	27,586	20,861
Lease obligations, current	3,374	2,583
Deferred revenue - related party, current	21,820	23,545
Other current liabilities		24
Total Current Liabilities	68,128	54,147
Deferred revenue - related party	43,046	49,297
Lease obligations	20,359	19,666
Asset retirement obligations	2,081	1,814
Deferred income tax liability	196	214
Other long-term liabilities	953
TOTAL LIABILITIES	134,763	125,138
COMMITMENTS (Note 14)
SHAREHOLDERS' EQUITY:
Ordinary Shares, $0.00003881 par value, 1,288,327,750 authorized, 44,548,925 and 44,189,150 shares issued and outstanding at December 31, 2021 and 2020, respectively	2	2
Capital in excess of par value	528,659	504,482
Accumulated other comprehensive loss	(2,671)	(4,897)
Accumulated deficit	(340,589)	(261,028)
Total Shareholders' Equity	185,401	238,559
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 320,164	$ 363,697

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.00003881	$ 0.00003881
Common stock, shares authorized	1,288,327,750	1,288,327,750
Common stock, shares issued	44,548,925	44,189,150
Common stock, shares outstanding	44,548,925	44,189,150

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
License revenue - related party	$ 37,701	$ 15,563
Operating expenses:
General and administrative	43,765	44,207
Research and development	67,128	33,910
Total operating expenses	110,893	78,117
Loss from operations	(73,192)	(62,554)
Other non-operating income (expense):
Foreign currency (loss) gain	(6,293)	3,426
Interest income	212	1,275
Interest expense	(288)	(139)
Net loss	(79,561)	(57,992)
Other comprehensive income (loss):
Foreign currency translation gain (loss)	2,226	(3,103)
Total comprehensive loss	(77,335)	(61,095)
Net loss	$ (79,561)	$ (57,992)
Basic net loss per ordinary share	$ (1.80)	$ (1.54)
Diluted net loss per ordinary share	$ (1.80)	$ (1.54)
Weighted-average number of ordinary shares outstanding, basic	44,139,655	37,724,189
Weighted-average number of ordinary shares outstanding, diluted	44,139,655	37,724,189

CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Ordinary Shares [Member] Public Placement [Member]	Ordinary Shares [Member] At-the-market offering [Member]	Ordinary Shares [Member] Visiogene License Agreement	Ordinary Shares [Member] Vector Neurosciences Acquisition [Member]	Ordinary Shares [Member] Acquisition of Bullseye Therapeutics Inc [Member]	Ordinary Shares [Member]	Capital in Excess of Par Value [Member] Public Placement [Member]	Capital in Excess of Par Value [Member] At-the-market offering [Member]	Capital in Excess of Par Value [Member] Visiogene License Agreement	Capital in Excess of Par Value [Member] Vector Neurosciences Acquisition [Member]	Capital in Excess of Par Value [Member] Acquisition of Bullseye Therapeutics Inc [Member]	Capital in Excess of Par Value [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]	Public Placement [Member]	At-the-market offering [Member]	Visiogene License Agreement	Vector Neurosciences Acquisition [Member]	Acquisition of Bullseye Therapeutics Inc [Member]	Total
Beginning Balance at Dec. 31, 2019						$ 1						$ 395,630	$ (1,794)	$ (203,036)						$ 190,801
Beginning Balance, Shares at Dec. 31, 2019						36,791,906
Exercise of share options												841								$ 841
Exercise of share options, shares						109,296														109,296
Share-based compensation												18,417								$ 18,417
Issuance of shares in connection with asset acquisitions										$ 7,685								$ 7,685
Issuance of shares in connection with asset acquisitions, shares				544,500
Other comprehensive income (loss)													(3,103)							(3,103)
Issuance of shares, net of issuance costs	$ 1						$ 69,252	$ 12,657							$ 69,253	$ 12,657
Issuance of shares, net of issuance costs, shares	5,750,000	993,448
Net loss														(57,992)						(57,992)
Balance at Dec. 31, 2020						$ 2						504,482	(4,897)	(261,028)						238,559
Balance, Shares at Dec. 31, 2020						44,189,150
Exercise of share options												1,709								$ 1,709
Exercise of share options, shares						186,638														186,638
Share-based compensation												20,784								$ 20,784
Issuance of shares in connection with equity method and other investments									$ 1,165								$ 1,165
Issuance of shares in connection with equity method and other investments, shares			75,000
Issuance of shares in connection with asset acquisitions											$ 519								$ 519
Issuance of shares in connection with asset acquisitions, shares					98,137
Other comprehensive income (loss)													2,226							2,226
Net loss														(79,561)						(79,561)
Balance at Dec. 31, 2021						$ 2						$ 528,659	$ (2,671)	$ (340,589)						$ 185,401
Balance, Shares at Dec. 31, 2021						44,548,925

CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Stock issuance costs	$ 5,141
Public Placement [Member]
Stock issuance costs	4,635
Public and Private Placements [Member]
Stock issuance costs	$ 506

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (79,561)	$ (57,992)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	20,784	18,417
Foreign currency loss (gain)	6,293	(3,426)
Depreciation and amortization	7,873	4,172
Net change in right-of-use assets and liabilities	161	(387)
Loss on disposal of equipment, furniture and fixtures	56	213
Gain on termination of lease liability		(144)
Loss on equity method investment	9
Amortization of interest on asset retirement obligations	148	136
Issuance of shares in connection with license agreement	976
Issuance of shares in connection with asset acquisition	1,020	7,685
Fair value adjustment	434
(Increase) decrease in operating assets:
Accounts receivable - related party	16,391	(15,402)
Prepaid expenses	(1,083)	(2,366)
Tax incentive receivable	310	(715)
Other current assets	2,161	(2,520)
Other assets	(457)	164
Increase (decrease) in operating liabilities:
Accounts payable	13,347	1,566
Accrued expenses	8,118	2,171
Other current liabilities	(23)	24
Deferred revenue - related party	(7,487)	(15,563)
Net cash used in operating activities	(10,530)	(63,967)
Cash flows from investing activities:
Purchase of property, plant and equipment	(46,351)	(20,924)
Payment for right-of-use asset	(8,866)	(13,968)
Purchase of intangible asset		(2,128)
Equity method and other investments	(6,500)
Net cash used in investing activities	(61,717)	(37,020)
Cash flows from financing activities:
Payments on lease obligations - financing leases	(1)	(23)
Exercise of share options	1,709	841
Proceeds from the issuance of ordinary shares		87,051
Issuance costs in connection with ordinary shares		(5,141)
Net cash provided by financing activities	1,708	82,728
Net decrease in cash and cash equivalents	(70,539)	(18,259)
Effect of exchange rate changes on cash	(1,278)	422
Cash and cash equivalents at beginning of year	209,520	227,357
Cash and cash equivalents at end of year	137,703	209,520
Supplemental disclosure of non-cash transactions:
Issuance of shares in connection with equity method and other investments	1,165
Fixed asset acquisition included in accounts payable and accrued expenses at end of year	7,178	1,615
Right-of-use assets obtained in exchange for lease liabilities	4,424	1,889
Asset retirement obligations in connection with leases	120
Issuance of shares in connection with asset acquisition	519	7,685
Supplemental disclosure of cash flow information:
Cash paid for interest	$ 139	$ 3

Principal Business Activity

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Principal Business Activity

1. Principal Business Activity

The Company

MeiraGTx Holdings plc and subsidiaries (the “Company” or “Meira Holdings”), an exempted company incorporated under the laws of the Cayman Islands, is a vertically integrated, clinical stage gene therapy company with six programs in clinical development and a broad pipeline of preclinical and research programs. The Company has core capabilities in viral vector design and optimization and gene therapy manufacturing, as well as a potentially transformative gene regulation technology. Led by an experienced management team, the Company has taken a portfolio approach by licensing, acquiring and developing technologies that give depth across both product candidates and indications. The Company’s initial focus is on three distinct areas of unmet medical need: ocular diseases, including inherited retinal diseases as well as large degenerative ocular diseases, neurodegenerative diseases and severe forms of xerostomia. Though initially focusing on the eye, central nervous system and salivary gland, the Company intends to expand its focus in the future to develop additional gene therapy treatments for patients suffering from a range of serious diseases. The Company also owns and operates a current good manufacturing practices, or cGMP, multi-product, multi-viral vector manufacturing facility in London, United Kingdom (“UK”), which includes fill and finish capabilities and can supply the Company’s clinical and potential commercial material. Additionally, on August 4, 2020, the Company entered into agreements to acquire the buildings for its second cGMP viral vector manufacturing facility and its first cGMP plasmid and DNA production facility in Shannon, Ireland to expand its manufacturing and supply chain capabilities. The Company closed on the acquisition of the first building in August 2020 and closed on the acquisition of the second building in January 2021.

Acquisitions

On October 4, 2021, the Company acquired Bullseye Therapeutics, Inc. (“Bullseye”), a company engaged in developing mechanisms to deliver retinal drugs and gene therapies to the eye. Bullseye was renamed MeiraGTx Therapeutics, Inc.

On April 9, 2020, the Company acquired Emrys Bio Inc. (“Emrys”), a pre-clinical biopharmaceutical company developing brain-derived neurotrophic factor gene therapy for treatment of genetic obesity disorders, as well as the development of gene therapy product candidates for other central nervous system diseases. Emrys was renamed MeiraGTx Bio, Inc.

These acquisitions are part of the Company’s continuing efforts to expand its focus to develop additional gene therapy treatments for patients suffering from a range of serious diseases. (See Note 3 for additional information).

Basis of Presentation

The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Liquidity

The Company has not yet achieved profitable operations. There is no assurance that profitable operations, if ever achieved, could be sustained on a continuing basis. In addition, development activities, clinical and preclinical testing, and commercialization of the Company’s product candidates will require significant additional financing. The Company’s accumulated deficit at December 31, 2021 totaled $340.6 million, and management expects to incur substantial losses in future periods. The success of the Company is subject to certain risks and uncertainties,

including among others, uncertainty of product development; competition in the Company’s field of use; uncertainty of capital availability; uncertainty in the Company’s ability to enter into agreements with collaborative partners; expanding and protecting the Company’s intellectual property portfolio; dependence on third parties; dependence on key personnel; the COVID-19 pandemic and mitigation measures. For the year ended December 31, 2021, the Company used $10.5 million in cash flows from operations and there are no assurances that the Company will generate positive cash flows in the future. Additionally, there are no assurances that the Company will be successful in obtaining an adequate level of financing for the development and commercialization of its product candidates.

As of December 31, 2021, the Company had cash and cash equivalents in the amount of $137.7 million, which consisted of depository and money market accounts. On January 30, 2019, the Company entered into a collaboration, option and license agreement with Janssen Pharmaceuticals, Inc. (“Janssen”), one of the Janssen Pharmaceuticals Companies of Johnson & Johnson (the “Collaboration Agreement”), for the research, development and commercialization of gene therapies for the treatment of inherited retinal diseases (“IRD”). Under the terms of the Collaboration Agreement, the Company received an upfront payment of $100.0 million in March 2019 and a $30.0 million milestone payment in December 2021. The Company also receives funding for certain research, manufacturing, clinical development and commercialization costs, potential additional milestone payments upon the achievement of such milestones and royalties on future net sales of products. The Company estimates that its cash and cash equivalents on hand and accounts receivable – related party at December 31, 2021 will be sufficient to cover its expenses for at least the next twelve months from the date of issuance of these consolidated financial statements.

Risks and Uncertainties

The Company operates in an industry that is subject to intense competition, government regulation and rapid technological change. The Company’s operations are subject to significant risk and uncertainties including financial, operational, technological, regulatory and other risks, including the potential risk of business failure.

There are also many uncertainties regarding the pandemic caused by the novel coronavirus, or COVID-19, and the Company continues to monitor the impact of the pandemic on all aspects of its business, including how the pandemic will impact its financial condition, liquidity, operations, clinical studies, employees, vendors, and industry. While the pandemic did not materially affect the Company's financial results and business operations in the year ended December 31, 2021 and 2020, the Company is unable to predict the impact that COVID-19 will have on its financial position and operating results in future periods due to numerous uncertainties. The Company will continue to assess the evolving impact of the COVID-19 pandemic and will make adjustments to its operations as necessary.

The Company’s capital resources and operations to date have been funded primarily with the proceeds from the Collaboration Agreement and private and public equity offerings. In the future, the Company may seek to raise additional capital through equity offerings, debt financings, marketing and distribution arrangements and other collaborations, strategic alliances and licensing arrangements or other sources to enable it to complete the development and potential commercialization of its product candidates. The COVID-19 outbreak and mitigation measures also have had, and may continue to have, an adverse impact on global economic conditions, which could have an adverse effect on the Company’s ability to raise capital when needed.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Consolidation

The accompanying consolidated financial statements include the accounts of Meira Holdings and its wholly owned subsidiaries:

MeiraGTx Limited, a limited company incorporated under the laws of England and Wales;

MeiraGTx, LLC, a Delaware limited liability company (“Meira LLC”);

MeiraGTx UK II Limited, a limited company incorporated under the laws of England and Wales (“Meira UK II”);

MeiraGTx Ireland DAC, a designated activity company incorporated under the laws of Ireland (“Meira Ireland”);

MeiraGTx Netherlands B.V., a private company with limited liability incorporated under the laws of the Netherlands (“Meira Netherlands”);

MeiraGTx Belgium, a private company with limited liability incorporated under the laws of Belgium (“Meira Belgium”);

BRI-Alzan, Inc., a Delaware corporation (“BRI-Alzan”);

MeiraGTx Bio Inc., a Delaware corporation (“Meira Bio”);

MeiraGTx B.V., a private company with limited liability incorporated under the laws of the Netherlands (“Meira B.V.”);

MeiraGTx Neurosciences, Inc., a Delaware corporation (“Meira Neuro”);

MeiraGTx Therapeutics, Inc., a Delaware corporation (“Meira Therapeutics”); and

MeiraGTx UK Limited, a limited company incorporated under the laws of England and Wales (“Meira UK”).

All intercompany balances and transactions between the consolidated companies have been eliminated in consolidation.

Use of Estimates

Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these consolidated financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. In preparing these consolidated financial statements, management used significant estimates in the following areas, among others: collaboration revenue, the accounting for research and development costs, share-based compensation, leases, asset retirement obligations and tax incentive receivable.

Additionally, the Company has made estimates of the impact of the COVID-19 pandemic within the consolidated financial statements and there may be changes to those estimates in future periods. Actual results may differ from these estimates.

Cash and Cash Equivalents

The Company considers all highly liquid instruments with an original maturity of 90 days or less at the time of purchase to be cash equivalents. Cash and cash equivalents consist of checking and money market accounts that are readily convertible into cash.

Financial Instruments

The carrying value of accounts receivable-related party, tax incentive receivable, other current assets, and accounts payable reported in the consolidated balance sheets equal or approximate fair value due to their short maturities.

Tax Incentive Receivable

Meira UK II is eligible to participate in a UK research and development tax incentive programs under which it is eligible to receive a cash refund from Her Majesty’s Revenue & Customs (“HMRC”) for a percentage of the qualified research and development costs expended by Meira UK II under the small and medium sized enterprises (“SME”) program and the research and development expenditures credit (“RDEC”) program. The SME cash refund is available to companies with less than 500 employees and annual aggregate revenue of less than 100.0 million euro or total aggregate assets less than 86.0 million euro during the reimbursable period. The Company’s estimate of the amount of cash refund it expects to receive related to the SME and RDEC programs is included in tax incentive receivable in the accompanying consolidated balance sheets and such amounts are recorded as a reduction of research and development expense in the statements of operations. During the years ended December 31, 2021 and 2020, the Company recorded reductions to research and development expenses of $5.4 million and $5.3 million, respectively.

In addition, the Company incurs Value Added Tax (“VAT”) on services provided by UK and EU vendors, which it is entitled to reclaim. The Company’s estimate of the amount of cash refund it expects to receive related to VAT was $1.9 million and $4.0 million as of December 31, 2021 and 2020, respectively, which is included in other current assets in the accompanying consolidated balance sheets.

Fair Value Measurements

Fair value is defined as the price that would be received upon sale of an asset or paid upon transfer of a liability in an orderly transaction between market participants at the measurement date and in the principal or most advantageous market for that asset or liability. The fair value should be calculated based on assumptions that market participants would use in pricing the asset or liability, not on assumptions specific to the entity. In addition, the fair value of liabilities should include consideration of non-performance risk including the Company’s own credit risk.

The Company follows ASC Topic 820, Fair Value Measurements and Disclosures, or ASC 820, for application to financial assets and liabilities. In addition to defining fair value, the standard expands the disclosure requirements around fair value and establishes a fair value hierarchy for valuation inputs. The hierarchy prioritizes the inputs into three levels based on the extent to which inputs used in measuring fair value are observable in the market. Each fair value measurement is reported in one of the three levels which are determined by the lowest level input that is significant to the fair value measurement in its entirety. These levels are:

●

Level 1: Observable inputs such as quoted prices in active markets for identical assets the reporting entity has the ability to access as of the measurement date;

●

Level 2: Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and

●

Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

The table below represents the values of the Company's financial assets and liabilities that are required to be measured at fair value on a recurring basis (in thousands):


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2021		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	66,585	$	66,585	$	—	$	—
Other long-term liabilities	$	953	$	953	$	—	$	—


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2020		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	186,938	$	186,938	$	—	0	—

Equity Method and Other Investments

The Company accounts for equity investments under the equity method of accounting when the requirements for consolidation are not met, and the Company has significant influence over the operations of the investee. Equity method investments are initially recorded at cost and subsequently adjusted for the Company’s share of net income or loss and cash contributions and distributions and are included in equity method and other investments in the accompanying consolidated balance sheets. Equity investments that do not result in consolidation and are not accounted for under the equity method are measured at fair value, with any changes in fair value recognized in net income (loss). For any such investments that do not have readily determinable fair values, the Company elects the measurement alternative to measure the investments at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Equity method investments are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. If it is determined that a loss in value of the equity method investment is other than temporary, an impairment loss is measured based on the excess of the carrying amount of an investment over its estimated fair value. Impairment analyses are based on current plans, intended holding periods, and available information at the time the analysis is prepared.

Concentrations of Credit Risk

The Company maintains its cash and cash equivalents primarily in depository and money market accounts within two large financial institutions in the United States and one large financial institution in the United Kingdom and Ireland. Cash balances deposited at these major financial banking institutions exceed the insured limit. The Company has not experienced any losses on its bank deposits and believes these deposits do not expose the Company to any significant credit risk.

Intangible Assets

Intangible assets consist of purchased rights to licensed technology as it relates to the Company’s manufacturing processes and has future alternative use in the Company’s operations. The licensed technology is being amortized on a straight-line basis over 7 years, which represents the estimated periods of benefit and the expected pattern of consumption (see Note 7).

Property, Plant and Equipment, Net

Property, plant and equipment are stated at cost, net of accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are depreciated over the lesser of their useful lives or the life of the lease (see Note 6).

The estimated useful lives of the asset categories are as follows:


Asset Category		Useful Lives
Computer and office equipment		3 years
Laboratory equipment		5 years
Manufacturing equipment		7 years
Furniture and fixtures		5 years
Leasehold improvements		lesser of useful life or remaining term of lease

Expenditures for leasehold improvements are capitalized, and expenditures for maintenance and repairs are expensed to operations as incurred.

ASC Topic 360, Property, Plant and Equipment, addresses the financial accounting and reporting for impairment or disposal of long-lived assets. The Company reviews the recorded values of long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset or group of assets may not be fully recoverable. The Company recorded no material impairment charges in 2021 or 2020.

Leases

The Company accounts for leases in accordance with ASC 842. The Company determines if an arrangement is a lease at contract inception. A lease exists when a contract conveys the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. The definition of a lease embodies two conditions: (1) there is an identified asset in the contract that is land or a depreciable asset (i.e., property, plant, and equipment), and (2) the Company has the right to control the use of the identified asset. The Company accounts for the lease and non-lease components as a single lease component.

From time to time the Company enters into direct financing lease arrangements that include a lessee obligation to purchase the leased asset at the end of the lease term, a bargain purchase option, or provides for minimum lease payments with a present value of 90% or more of the fair value of the leased asset at the date of lease inception.

Operating leases where the Company is the lessee are included in right-of-use (“ROU”) assets and lease obligations are included on the Company’s consolidated balance sheets. The lease obligations are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date and subsequent reporting periods.

Finance leases where the Company is the lessee are included in ROU assets – finance leases, net and lease obligations on the Company’s consolidated balance sheets. The lease obligations are initially measured in the same manner as for operating leases and are subsequently measured at amortized cost using the effective interest method.

Key estimates and judgments include how the Company determined (1) the discount rate used to discount the unpaid lease payments to present value, (2) lease term and (3) lease payments.

ASC 842 requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. As most of the Company’s leases where it is the lessee do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company’s incremental borrowing rate for a lease is the rate of interest it would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. The Company uses the implicit rate when readily determinable.

The lease term for all of the Company’s leases includes the non-cancellable period of the lease plus any additional periods covered by either a lessee option to extend (or not to terminate) the lease that is reasonably certain to be exercised, or an option to extend (or not to terminate) the lease controlled by the lessor.

The ROU asset is initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date less any lease incentives received.

For operating leases, the ROU asset is subsequently measured throughout the lease term at the carrying amount of the lease liability, minus any accrued lease payments, less the unamortized balance of lease incentives received. Lease expense for lease payments is recognized on a straight-line basis over the lease term.

For finance leases, the ROU asset is subsequently amortized using the straight-line method from the lease commencement date to the earlier of the end of its useful life or the end of the lease term unless the lease transfers ownership of the underlying asset, or the Company is reasonably certain to exercise an option to purchase the underlying asset. In those cases, the ROU asset is amortized over the useful life of the underlying asset. Amortization of the ROU asset is recognized and presented separately from interest expense on the lease liability.

The Company has elected not to recognize ROU assets and lease liabilities for all short-term leases that have a lease term of 12 months or less at lease commencement. Lease payments associated with short-term leases are recognized as an expense on a straight-line basis over the lease term.

Asset Retirement Obligations

Accounting for asset retirement obligations requires legal obligations associated with the retirement of long-lived assets to be recognized at fair value when incurred and capitalized as part of the related long-lived asset. In the absence of quoted market prices, the Company estimates the fair value of its asset retirement obligations using Level 3 present value techniques, in which estimates of future cash flows associated with retirement activities are discounted using a credit-adjusted risk-free rate of 8%. Asset retirement obligations currently reported on the Company’s consolidated balance sheets were measured during a period of historically low interest rates. The impact on measurements of new asset retirement obligations using different rates in the future may be significant.

The Company uses estimates to determine the asset retirement obligations at the end of the lease term and discounts such asset retirement obligations using an estimated discount rate. Interest on the discounted asset retirement obligation is amortized over the term of the lease using the effective interest method and is recorded as interest expense in the consolidated statements of operations and comprehensive loss.

The change in asset retirement obligations is as follows (in thousands):


	For the Years Ended December 31,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Additional asset retirement obligations during the period		120		—
Amortization of interest		148		136
Effects of exchange rate		(1)		23
Balance at end of period	$	2,081	$	1,814

Share-Based Compensation Expense

Options

The Company grants share options to employees, non-employee members of the Company’s board of directors and non-employee consultants as compensation for services performed. Employee and non-employee members of the board of directors’ awards of share-based compensation are accounted for in accordance with ASC 718, Compensation - Stock Compensation, or ASC 718. ASC 718 requires all share-based payments to employees and non-employee directors, including grants of share options, to be recognized in the consolidated statement of operations and comprehensive loss based on their grant date fair values. The grant date fair value of share options is estimated using the Black-Scholes option valuation model.

Using this model, fair value is calculated based on assumptions with respect to (i) the fair value of the Company’s ordinary shares on the grant date; (ii) expected volatility of the Company’s ordinary share price, (iii) the periods of time over which the optionees are expected to hold their options prior to exercise (expected term), (iv) expected dividend yield on the Company’s ordinary shares, and (v) risk-free interest rates.

As there had been no public market for the Company’s ordinary shares until the Company’s initial public offering (“IPO”) on June 7, 2018, the estimated fair value of the ordinary shares until that time had been determined by the Company’s board of directors as of the date of each option grant, with input from management, considering the most recently available third-party valuations of ordinary shares and the board of directors’ assessment of additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the date of the grant. The assumptions underlying these valuations represented management’s best estimate, which involved inherent uncertainties and the application of management’s judgment. As a result, if the Company had used different assumptions or estimates, the fair value of its ordinary shares and its share-based compensation expense could have been materially different.

The fair value of ordinary shares after the Company’s IPO was determined based upon the closing share price on the date of grant.

Since the Company’s ordinary shares had not been traded on a public exchange prior to the Company’s IPO and have only been traded on a public exchange for a short period of time since the Company’s IPO, the Company believes that it does not have sufficient company-specific information available to determine the expected term based on its historical data. As a result, the expected term of share options granted to the optionees is determined using the average of the vesting period and contractual life of the option, an accepted method for the Company’s option grants under the Securities and Exchange Commission’s (“SEC”) Staff Accounting Bulletin No. 107 and No. 110, Share-Based Payment.

Similarly, the Company believes that its future volatility could differ materially during the expected term from the volatility that would be calculated from its historical share prices to date. Consequently, expected volatility is based on an analysis of guideline companies in accordance with ASC 718. The expected dividend yield is zero as the Company has never paid dividends and does not currently anticipate paying any in the foreseeable future. Risk-free interest rates are based on quoted U.S. Treasury rates for securities with maturities approximating the option’s expected term.

Restricted Shares

In connection with certain employment, service and research agreements, the Company has granted restricted ordinary shares as compensation. The ordinary shares are recognized in the consolidated statements of operations and comprehensive loss based on their grant date fair values. Compensation cost relating to share grants with service-based graded vesting schedules is recognized based on the vesting schedule.

Restricted Share Units

The Company grants restricted share units (“RSUs”) to employees, non-employee members of the Company’s board of directors and non-employee consultants as compensation for services performed. Awards of RSUs are accounted for in accordance with ASC 718, Compensation - Stock Compensation, or ASC 718. ASC 718 requires all share-based payments to employees, non-employee members of the Company’s board of directors and non-employee consultants, including grants of RSUs, to be recognized in the consolidated statement of operations and comprehensive loss based on their grant date fair values. The grant date fair value of RSUs is determined using the closing market price of the Company’s ordinary shares on the date of grant.

Collaboration Arrangements

The Company evaluates its collaborative arrangements pursuant to ASC 808, Collaborative Arrangements (“ASC 808”) and ASC 606, Revenue from Contracts with Customers (“ASC 606”). The Company considers the nature and contractual terms of collaborative arrangements and assesses whether the arrangement involves a joint operating activity pursuant to which the Company is an active participant and is exposed to significant risks and rewards with respect to the arrangement. If the Company is an active participant and is exposed to significant risks and rewards with respect to the arrangement, the Company accounts for the arrangement as a collaboration under ASC 808. To date, the Company has entered into two separate collaboration agreements, both of which are with Janssen, which were determined to be within the scope of ASC 808.

ASC 808 does not address recognition or measurement matters related to collaborative arrangements. Payments between participants pursuant to a collaborative arrangement that are within the scope of other authoritative accounting literature on income statement classification are accounted for using the relevant provisions of that literature. If the payments are not within the scope of other authoritative accounting literature, the income statement classification for the payments is based on an analogy to authoritative accounting literature or if there is no appropriate analogy, a reasonable, rational and consistently applied accounting policy election. Payments received from a collaboration partner to which this policy applies may include upfront payments in respect of a license of intellectual property, development and commercialization-based milestones, and royalties.

Refer to the discussion in Note 12 for further information related to the accounting for the Collaboration Agreement.

Revenue Recognition

Arrangements with collaborators may include licenses to intellectual property, research and development services, manufacturing services for clinical and commercial supply, and participation on joint steering committees. The Company evaluates the promised goods or services to determine which promises, or group of promises, represent

performance obligations. In contemplation of whether a promised good or service meets the criteria required of a performance obligation, the Company considers the stage of development of the underlying intellectual property, the capabilities and expertise of the customer relative to the underlying intellectual property, and whether the promised goods or services are integral to or dependent on other promises in the contract. When accounting for an arrangement that contains multiple performance obligations, the Company must develop judgmental assumptions, which may include market conditions, reimbursement rates for personnel costs, development timelines and probabilities of regulatory success to determine the stand-alone selling price for each performance obligation identified in the contract.

When the Company concludes that a contract should be accounted for as a combined performance obligation and recognized over time, the Company must then determine the period over which revenue should be recognized and the method by which to measure revenue. The Company generally recognizes revenue using a cost-based input method.

The Collaboration Agreement with Janssen is accounted for under ASC 808, however, as ASC 808 does not address recognition or measurement matters such as determining the appropriate unit of accounting or when the recognition criteria are met, the Company accounts for the consideration received from Janssen in accordance with ASC 606. In accordance with ASC 606, the Company recognizes revenue when its customer or collaborator obtains control of promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that the Company determines are within the scope of ASC 606, it performs the following five steps:

identify the contract(s) with a customer;

ii.

identify the performance obligations in the contract;

iii.

determine the transaction price;

iv.

allocate the transaction price to the performance obligations within the contract; and

recognize revenue when (or as) the entity satisfies a performance obligation.

The Company only applies the five-step model to contracts when it determines that it is probable it will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer.

At contract inception, once the contract is determined to be by analogy within the scope of ASC 606, the Company assesses the goods or services promised within the contract to determine whether each promised good or service is a performance obligation. The promised goods or services in the Company’s arrangements typically consist of a license to the Company’s intellectual property and research, development and manufacturing services. The Company may provide options to additional items in such arrangements, which are accounted for as separate contracts when the customer elects to exercise such options, unless the option provides a material right to the customer. Performance obligations are promises in a contract to transfer a distinct good or service to the customer that (i) the customer can benefit from on its own or together with other readily available resources, and (ii) is separately identifiable from other promises in the contract. Goods or services that are not individually distinct performance obligations are combined with other promised goods or services until such combined group of promises meet the requirements of a performance obligation.

The Company determines transaction price based on the amount of consideration the Company expects to receive for transferring the promised goods or services in the contract. Consideration may be fixed, variable, or a combination of both. At contract inception for arrangements that include variable consideration, the Company estimates the probability and extent of consideration it expects to receive under the contract utilizing either the most

likely amount method or expected amount method, whichever best estimates the amount expected to be received. The Company then considers any constraints on the variable consideration and includes in the transaction price variable consideration to the extent it is deemed probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved.

The Company then allocates the transaction price to each performance obligation based on the relative standalone selling price and recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) control is transferred to the customer and the performance obligation is satisfied. For performance obligations which consist of licenses and other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

The Company records amounts as accounts receivable when the right to consideration is deemed unconditional. When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded as deferred revenue.

Amounts received prior to satisfying the revenue recognition criteria are recognized as deferred revenue in the Company’s consolidated balance sheet. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue – related party, current. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue – related party.

The Company’s collaboration revenue arrangements include the following:

Up-front License Fees: If a license is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from nonrefundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

Milestone Payments: At the inception of an agreement that includes research and development milestone payments, the Company evaluates each milestone to determine when and how much of the milestone to include in the transaction price. The Company first estimates the amount of the milestone payment that the Company could receive using either the expected value or the most likely amount approach. The Company primarily uses the most likely amount approach as that approach is generally most predictive for milestone payments with a binary outcome. Then, the Company considers whether any portion of that estimated amount is subject to the variable consideration constraint (that is, whether it is probable that a significant reversal of cumulative revenue would not occur upon resolution of the uncertainty.) The Company updates the estimate of variable consideration included in the transaction price at each reporting date which includes updating the assessment of the likely amount of consideration and the application of the constraint to reflect current facts and circumstances.

Royalties: For arrangements that include sales-based royalties, including milestone payments based on a level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company will recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any revenue related to sales-based royalties or milestone payments based on the level of sales.

Research and Development Services: The Company is incurring research and development costs, with Janssen responsible for up to 100% of the costs, depending on the type of research and development services being performed. The Company records costs associated with the development activities as research and development expenses in the consolidated statement of operations and comprehensive loss consistent with ASC 730, Research and Development. The reimbursement of the research and development costs by Janssen is representative of the joint risk sharing nature of the arrangement. The Company considered the guidance in ASC 808 and recognizes the payments received from Janssen as a reduction to research and development expense when the related costs are incurred.

Research and Development

Research and development costs are charged to expense as incurred. These costs include, but are not limited to, employee-related expenses, including salaries, benefits and travel of the Company’s research and development personnel; expenses incurred under agreements with contract research organizations and investigative sites that conduct clinical and preclinical studies and for the drug product for the clinical studies and preclinical activities; facilities; supplies; rent, insurance, certain legal fees, share-based compensation, depreciation, other costs associated with clinical and preclinical activities and regulatory operations and acquisition of in process research and development write-offs. Research funding under collaboration agreements and refundable research and development credits / tax credits are recorded as an offset to these costs.

Costs for certain development activities, such as Company funded outside research programs, are recognized based on an evaluation of the progress to completion of specific tasks with respect to their actual costs incurred. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected in the consolidated financial statements as prepaid or accrued research and development expenses, as the case may be.

Foreign Currencies

The Company’s consolidated financial statements are presented in U.S. dollars, the reporting currency of the Company. The financial position and results of operations of Meira UK II, Meira Ireland, Meira Netherlands, Meira Belgium and Meira B.V. are measured using the foreign subsidiaries’ local currency as the functional currency. These entities’ cash accounts holding U.S. dollars are remeasured based upon the exchange rate at the date of remeasurement with the resulting gain or loss included in the consolidated statements of operations and comprehensive loss. Expenses of such subsidiaries have been translated into U.S. dollars at average exchange rates prevailing during the period. Assets and liabilities have been translated at the rates of exchange on the consolidated balance sheet dates. The resulting translation gain and loss adjustments are recorded directly as a separate component of shareholders' equity and as other comprehensive loss on the consolidated statements of operations and comprehensive loss.

Income Taxes

Income taxes are recorded in accordance with ASC Topic 740, Income Taxes, or ASC 740, which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Realization of net deferred tax assets is dependent on future taxable income. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some, or all, of the deferred tax assets will not be realized. Realization of net deferred tax assets is dependent on future taxable income (see Note 11).

The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. As of December 31, 2021 and 2020, the Company recorded unrecognized tax positions of $0.7 and $0.5 million, respectively. No interest and penalties have been accrued relative to the unrecognized tax positions.

The Company is required to estimate income taxes in each of the jurisdictions in which it operates.

Net Loss per Ordinary Share

Basic net loss per ordinary share is computed by dividing net loss by the weighted average number of shares of the Company’s ordinary shares outstanding during the period of computation. Diluted net loss per ordinary share is computed similar to basic net loss per share except that the denominator is increased to include the number of additional ordinary shares that would have been outstanding if the ordinary share equivalents had been issued at the beginning of the year and if the additional ordinary shares were dilutive (treasury stock method) or the two-class method, whichever is more dilutive. For all periods presented, basic and diluted net loss per ordinary share are the same as any additional ordinary share equivalents would be anti-dilutive.

The following securities are considered to be ordinary share equivalents, but were not included in the computation of diluted net loss per ordinary share because to do so would have been anti-dilutive:


	December 31,	December 31,
	2021	2020
Share options	5,924,690	4,824,771
Restricted share units	1,415,000	545,000
Restricted ordinary shares subject to forfeiture	173,097	290,000
	7,512,787	5,659,771

Other Comprehensive Loss

Other comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The only component of other comprehensive loss impacting the Company is foreign currency translation.

Segment Information

Management has concluded it has a single reporting segment for purposes of reporting financial condition and results of operations.

The Company’s license revenue, research funding and deferred revenue from its Collaboration Agreement are generated in the United Kingdom.

The following table summarizes non-current assets by geographical area (in thousands):


	December 31,		December 31,
	2021		2020
United States	$	23,636	$	17,536
United Kingdom		43,349		44,487
European Union		69,936		29,098
	$	136,921	$	91,121

Recent Accounting Pronouncements Not Yet Adopted

In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which adds a new Topic 326 to the Codification and removes the thresholds that companies apply to measure credit losses on financial instruments measured at amortized cost, such as loans, receivables, and held-to-maturity debt securities. Under current GAAP, companies generally recognize credit losses when it is probable that the loss has been incurred. The revised guidance will remove all recognition thresholds and will require companies to recognize an allowance for credit losses for the difference between the amortized cost basis of a financial instrument and the amount of amortized cost that the company expects to collect over the instrument’s contractual life. ASU 2016-13 also amends the credit loss measurement guidance for available-for-sale debt securities and beneficial interests in securitized financial assets. The guidance is applicable for fiscal years beginning after December 15, 2019 and interim periods within those years, however, the FASB extended the effective date for smaller reporting companies to fiscal years beginning after December 15, 2022. The Company is currently evaluating the potential impact of the adoption of this standard on its related disclosures.

Acquisitions

12 Months Ended

Dec. 31, 2021

Business Combinations [Abstract]

Acquisitions

3. Acquisitions

Bullseye Therapeutics, Inc.

On October 4, 2021 (the “Bullseye Closing Date”), the Company acquired the stock of Bullseye, a company engaged in developing mechanisms to deliver retinal drugs and gene therapies to the eye. As a result, Bullseye is a wholly-owned subsidiary of the Company and was renamed MeiraGTx Therapeutics, Inc.

In connection with the acquisition of Bullseye, the consideration to Bullseye’s selling stockholders consisted of an aggregate of 80,276 of the Company’s ordinary shares of which (i) 12,040 ordinary shares were issued on the Bullseye Closing Date, (ii) 28,097 restricted ordinary shares were issued on the Bullseye Closing Date, with 50% of such restricted ordinary shares scheduled to vest on each of the first and second anniversaries of the Bullseye Closing Date, and (iii) 40,139 ordinary shares will be issued 18 months following the Bullseye Closing Date, provided that the shares described in clauses (ii) and (iii) are subject to certain indemnification claims under the Bullseye Merger Agreement. The Company also assumed $0.5 million of Bullseye’s liabilities (“Assumed Liabilities”). Total consideration of $1.5 million was based on the closing price of the Company’s ordinary shares of $13.31 per share on October 1, 2021, plus the Assumed Liabilities.

The Company determined this transaction represented an asset acquisition as substantially all of the value was in the intellectual property as defined by ASC 805, Business Combinations (“ASC 805”). The asset acquisition of in-process research and development was recorded at a fair value of $1.5 million as of October 4, 2021. The acquired in process research and development was immediately charged to research and development expense in the consolidated statement of operations and comprehensive loss as of the acquisition date since the Company determined that there was no additional alternative use of these assets.

The 40,139 ordinary shares that are to be issued 18 months following the Bullseye Closing Date were recorded as a liability at a fair value of $0.5 million on the Bullseye Closing Date. At December 31, 2021, the liability was revalued to $1.0 million based upon the closing price of the Company’s ordinary shares of $23.74 per share on December 31, 2021. The $0.5 million change in fair value was recorded as research and development expense for the year ended December 31, 2021.

Emrys Bio Inc.

On April 9, 2020 (the “Emrys Closing Date”), the Company acquired Emrys, a pre-clinical biopharmaceutical company developing brain-derived neurotrophic factor gene therapy for treatment of genetic obesity disorders, as well as the development of gene therapy product candidates for other central nervous system diseases. The

Company acquired Emrys pursuant to an Agreement and Plan of Merger (the “Emrys Merger Agreement”), dated as of April 9, 2020, by and among the Company, Emrys, and EB Acquisition, Inc., a wholly-owned subsidiary of the Company (“Merger Sub”), the Emrys stockholders and the Emrys stockholder representative, pursuant to which Merger Sub was merged with and into Emrys, with Emrys being the surviving corporation (the “Emrys Merger”). As a result of the Emrys Merger, Emrys became a wholly-owned subsidiary of the Company and was renamed MeiraGTx Bio Inc.

As part of the entry into the Emrys Merger Agreement, the parties to the Agreement and Plan of Merger (the “Vector Merger Agreement”), dated October 5, 2018, entered into an Amendment and Waiver to the Vector Merger Agreement by and among the Company, VN Acquisition, Inc., VN Acquisition 2, Inc., the former Vector Neurosciences Inc. (“Vector”) stockholders and the Vector stockholder representative, to terminate and waive all milestone payments payable under the Vector Merger Agreement that were otherwise required if specified regulatory milestones were met, and to terminate and waive all royalty payments that were otherwise required to be paid under the Vector Merger Agreement. Several of the selling Emrys stockholders were also stockholders of Vector.

In connection with the acquisition of Emrys and the termination and waiver of the milestone and royalty payments otherwise required under the Vector Merger Agreement, the consideration to Emrys selling stockholders consisted of an aggregate of 580,000 of the Company’s ordinary shares of which (i) 232,000 ordinary shares were issued on the Emrys Closing Date, (ii) 290,000 restricted ordinary shares were issued on the Emrys Closing Date, with 50% of such restricted ordinary shares scheduled to vest on each of the first and second anniversaries of the Emrys Closing Date, and (iii) 58,000 ordinary shares will be issued 18 months following the Emrys Closing Date, provided that the shares described in clauses (ii) and (iii) are subject to certain indemnification claims under the Emrys Merger Agreement. Total consideration of $7.7 million was based on the closing price of the Company’s ordinary shares of $13.25 per share on the Closing Date.

The Company determined this transaction represented an asset acquisition as substantially all of the value was in the intellectual property as defined by ASC 805, Business Combinations (“ASC 805”). The asset acquisition of in-process research and development was recorded at a fair value of $7.7 million as of April 9, 2020. The acquired in process research and development was immediately charged to research and development expense in the consolidated statement of operations and comprehensive loss as of the acquisition date since the Company determined that there was no additional alternative use of these assets.

Equity Method and Other Investments

12 Months Ended

Dec. 31, 2021

Long-term Investments [Abstract]

Equity Method and Other Investments

4. Equity Method and Other Investments

The Company’s investments consist of the following (in thousands):


		December 31, 2021
Investee	Investment Type	Ownership Percentage		Carrying Value		Cost Basis
Visiogene LLC	Equity Method Investment	25	%	$	5,156	$	5,165
Other	Equity Investment	3	%		1,500		1,500
Total equity method and other investments				$	6,656	$	6,665

Visiogene LLC

On January 4, 2021, the Company and Visiogene LLC (“Visiogene”) entered into a License and Investment Agreement (“Visiogene License Agreement”) for an exclusive, worldwide license to certain of Visiogene’s intellectual property relating to ocular gene therapy. Concurrently, the Company and Visiogene entered into a Preferred Unit Purchase Agreement (“Visiogene Unit Agreement”) pursuant to which the Company purchased 3,000,000 Visiogene preferred units. In connection with the two Visiogene agreements, the Company paid $5.0

million in cash and issued to Visiogene 75,000 ordinary shares of the Company with a fair market value of $1.2 million based on the closing price of the Company’s ordinary shares on the date of closing.

The Company accounted for the payments under the Visiogene License Agreement and Visiogene Unit Agreement as a basket transaction and allocated $1.0 million to the Visiogene License Agreement and the remaining $5.2 million was allocated to the Visiogene preferred units. The $1.0 million allocated to the Visiogene License Agreement was expensed as acquired in-process research and development as the Company determined there was no alternative future use. The Company accounts for this investment using the equity method of accounting.

During the year ended December 31, 2021, the Company recorded research and development expenses in the amount of $0.01 million related to the Company’s share of Visiogene’s losses.

Prepaid Expenses

12 Months Ended

Dec. 31, 2021

Other Income and Expenses [Abstract]

Prepaid Expenses

5. Prepaid Expenses

Prepaid expenses at December 31, 2021 and 2020 consist of the following (in thousands):


	December 31,		December 31,
	2021		2020
Clinical trial costs	$	2,322	$	1,625
Insurance		2,122		2,903
Dues and license fees		1,185		515
Research and development		991		164
Manufacturing costs		624		1,395
Rent and facilities costs		455		169
Other		403		311
	$	8,102	$	7,082

Property, Plant and Equipment, net

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment, net

6. Property, Plant and Equipment, net

Property, plant and equipment, net at December 31, 2021 and 2020 consist of the following (in thousands):


	December 31,		December 31,
	2021		2020
Leasehold improvements	$	60,878	$	33,777
Manufacturing equipment		12,156		7,021
Laboratory equipment		10,868		7,350
Computer and office equipment		5,750		3,713
Furniture and fixtures		687		568
		90,339		52,429
Less: Accumulated depreciation		(14,479)		(8,387)
	$	75,860	$	44,042

In connection with certain operating leases, the Company has determined that it has asset retirement obligations in the aggregate amount of $4.1 million at the end of those leases. The Company discounted the asset retirement obligations using an 8% discount rate and recorded an asset retirement obligation in the aggregate amount of $1.9 million, which is included in leasehold improvements and is being depreciated over the term of the respective leases.

Depreciation expense related to property, plant and equipment was $6.3 million and $3.7 million for the years ended December 31, 2021 and 2020, respectively.

Intangible Assets

12 Months Ended

Dec. 31, 2021

Intangible Assets

Intangible Assets

7.	Intangible Assets

In November 2020, the Company entered into a non-exclusive, royalty-free technology license agreement that required the Company to pay an upfront payment to the licensor of $2.1 million. The Company accounted for the transaction as an asset acquisition and recorded an intangible asset as it was determined to have alternative future uses in connection with the Company’s manufacturing capabilities.

The following table presents the details of the Company’s intangible assets as of December 31, 2021 and 2020 (in thousands):


	December 31,		December 31,
	2021		2020
Licensed Technology	$	2,119	$	2,145
Less: Accumulated amortization		(328)		(26)
	$	1,791	$	2,119

The intangible asset will be amortized over a period of seven years. Amortization expense of $0.3 million and $0.02 million was recorded as a component of research and development expenses for the years ended December 31, 2021 and 2020, respectively.

As of December 31, 2021, the expected amortization expense for the next five years and thereafter is as follows (in thousands):


	Amortization
	Expense
2022	$	306
2023		306
2024		306
2025		306
2026		306
Thereafter		261
Total amortization	$	1,791

Accrued Expenses

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses

8. Accrued Expenses

Accrued expenses at December 31, 2021 and 2020 were comprised of the following (in thousands):


	December 31,		December 31,
	2021		2020
Clinical trial costs	$	12,524	$	10,261
Compensation and benefits		6,029		3,791
Manufacturing costs		2,889		1,886
Fixed assets		2,077		949
Research and development		1,735		893
Professional fees		1,018		1,219
Consulting		858		1,047
Other		456		815
	$	27,586	$	20,861

Share-Based Compensation

12 Months Ended

Dec. 31, 2021

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-Based Compensation

9. Share-Based Compensation

Equity Incentive Plans

The Company’s 2018 Incentive Award Plan and 2016 Equity Incentive Plan (collectively, the “Plans”), were adopted by the Company’s board of directors and shareholders. Under the Plans, the Company has granted share options and restricted share units (“RSUs”) to selected officers, employees, non-employee members of the Company’s board of directors and non-employee consultants. The Company’s board of directors or a committee thereof administers the Plans. Upon the adoption of the 2018 Incentive Award Plan, the Company ceased issuing awards under the 2016 Equity Incentive Plan. The number of shares available for issuance under the 2018 Incentive Award Plan are increased on January 1 of each calendar year beginning in 2019 and ending in and including 2028, by an amount equal to the lesser of (A) 4% of the ordinary shares outstanding on the final day of the immediately preceding calendar year and (B) a smaller number of shares determined by the Company's board of directors. Under the 2018 Incentive Award Plan the Company initially reserved up to 3,054,996 shares for issuance, which has been increased to 7,388,448 as of December 31, 2021. As of December 31, 2021, 1,195,477 shares remain available for future issuance. In January 2022, the number of shares available for issuance under the 2018 Incentive Award Plan increased by 1,778,500 shares. Also, in January 2022, the Company granted 2,186,200 options and restricted share units to certain executives, employees and consultants, in each case, under the 2018 Incentive Award Plan.

Options

A summary of the Company’s share option activity related to employees, non-employee members of the board of directors and non-employee consultants as of and for the years ended December 31, 2021 and 2020 is as follows (in thousands, except share and per share amounts):


					Weighted-
			Weighted-		Average
			Average		Remaining
		Number of	Exercise		Contractual
		Options	Price		Life (years)
Outstanding at December 31, 2019		3,645,360	$	9.31
Granted		1,666,500	$	15.91
Exercised		(109,296)	$	7.69
Expired		—	$	—
Forfeited		(377,793)	$	15.71
Outstanding at December 31, 2020		4,824,771	$	11.85	7.67	years
Granted		1,667,700	$	15.53
Exercised		(186,638)	$	9.16
Expired		—	$	—
Forfeited		(381,143)	$	12.22
Outstanding at December 31, 2021		5,924,690	$	13.16	7.40	years
Options exercisable at December 31, 2021		3,275,644	$	10.95	6.48	years
Aggregate intrinsic value of options outstanding as of December 31, 2021	$	62,702
Aggregate intrinsic value of options exercisable as of December 31, 2021	$	41,884

Options granted under the Plans have a maximum contractual term of ten years. Options granted generally vest 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months. Options granted to directors when they join the board generally vest in 36 equal monthly installments following the date of grant, and annual options granted to directors generally vest on the earlier of the first anniversary of the date of grant or the day before the Company’s next annual meeting of shareholders after the date of grant.

The total share-based compensation expense recorded in connection with the options was $14.8 million and $12.9 million, of which $6.2 million and $7.0 million was recorded as general and administrative expense and $8.6 million and $5.9 million was recorded as research and development expense during the years ended December 31, 2021 and 2020, respectively.

The total fair value of options vested during the years ended December 31, 2021 and 2020 was $14.4 million and $8.2 million, respectively.

The weighted average grant date fair value of options granted during the years ended December 31, 2021 and 2020 was $11.44 and $11.87, respectively. The grant date fair values of the share options granted were estimated using the Black-Scholes option valuation model with the following ranges of assumptions (see Note 2):


	2021	2020
Risk-free interest rate	0.62 - 1.39%	0.32 - 2.56%
Expected volatility	90%	90%
Expected dividend yield	0%	0%
Expected life (in years)	5.5 - 6.1	5.5 - 6.1

As of December 31, 2021, the total compensation expense relating to unvested options granted that had not yet been recognized was $26.1 million, which is expected to be realized over a period of 4.0 years. The Company will issue shares upon exercise of options from ordinary shares reserved under the Plans.

Restricted Share Units

A summary of the Company’s RSU activity related to employees, non-employee members of the board of directors and non-employee consultants for the years ended December 31, 2021 and 2020 is as follows:


		Weighted-
	Number of	Average
	Restricted	Grant Date
	Share Units	Fair Value
Outstanding at December 31, 2019	—	$	—
Granted	545,000	$	20.02
Vested	—	$	—
Forfeited	—	$	—
Outstanding at December 31, 2020	545,000	$	20.02
Granted	870,000	$	15.36
Vested	—	$	—
Forfeited	—	$	—
Outstanding at December 31, 2021	1,415,000	$	17.16

RSUs granted generally vest 50% on the second anniversary of the date of grant and 25% on the third and fourth anniversaries of the date of grant. Annual RSUs granted to directors generally vest in a single installment on the earliest to occur of the first anniversary of the grant date or the day immediately prior to the date of the next annual meeting of the Company’s shareholders occurring after the date of grant. The RSUs granted to the directors in June 2021 will be paid on or within 30 days after the date a director ceases to serve on the board. For RSUs granted in future years, the directors will be able to elect whether to defer the payment of their annual RSU awards under the Deferred Compensation Plan for Non-Employee Directors, which was adopted by the board on December 17, 2021. The related share-based compensation expense, which is recognized ratably over the requisite service period, is

included in general and administrative and research and development expenses, as applicable, in the consolidated statements of operations and comprehensive loss.

Total share-based compensation expense recorded in connection with the RSUs was $6.0 million and $2.6 million, of which $4.9 million and $2.5 million was recorded as general and administrative expense and $1.1 million and $0.1 million was recorded as research and development expense during the years ended December 31, 2021 and 2020, respectively.

As of December 31, 2021, the total compensation expense relating to unvested RSUs granted that had not yet been recognized was $15.6 million, which is expected to be realized over a period of 3.7 years.

Restricted Ordinary Shares

On June 7, 2018, 1,306,348 restricted ordinary shares, which represented 5% of the fully-diluted outstanding shares of the Company as of such date, were issued to certain members of senior management in accordance with their employment agreements. One-third of such shares vested immediately, with the balance vesting quarterly over the next eight quarters beginning three months after the effectiveness of the Company’s registration statement on Form S-1 filed with the SEC on June 7, 2018 (the “Registration Statement”). The shares were valued at $15.00 per share and the related share-based compensation expense, which is recognized over the requisite service period, is included in general and administrative expenses in the consolidated statements of operations and comprehensive loss. Additionally, under the terms of the employment agreements, the Company was required to pay the income taxes incurred by the grantees in connection with the grant of those restricted shares.

These restricted ordinary shares were fully vested as of June 2020.

Total compensation expense in connection with the issuance of those restricted ordinary shares, in the amount of $6.5 million, of which $2.9 million was share-based and $3.6 million was paid in cash, was recorded as general and administrative expense during the year ended December 31, 2020.

During the years ended December 31, 2021 and 2020 the Company recognized total share-based compensation expense in the accompanying consolidated statements of operations and comprehensive loss as follows (in thousands):


	2021		2020
Research and development	$	9,685	$	6,026
General and administrative		11,099		12,391
Total share-based compensation	$	20,784	$	18,417

The Company does not expect to realize any tax benefits from its share option activity or the recognition of share-based compensation expense because the Company currently has net operating losses and has a full valuation allowance against its deferred tax assets. Accordingly, no amounts related to excess tax benefits have been reported in cash flows from operations or cash flows from financing activities for the years ended December 31, 2021 and 2020.

Ordinary Shares

12 Months Ended

Dec. 31, 2021

Equity [Abstract]

Ordinary Shares

10. Ordinary Shares

2021

Equity Method and Other Investments

As discussed in Note 3, on January 4, 2021, the Company issued 75,000 ordinary shares in connection with the Visiogene transaction in the amount of $1.2 million.

Acquisitions

As discussed in Note 3, on October 4, 2021 the Company issued 12,040 ordinary shares in connection with the Bullseye acquisition.

Also discussed in Note 3, on October 9, 2021, the Company issued 58,000 ordinary shares in connection with the Emrys acquisition.

2020

Public Offering

In November 2020, the Company issued 5,000,000 ordinary shares in a public offering for gross proceeds of $64.3 million. In December 2020, the underwriter exercised its overallotment provision and the Company issued an additional 750,000 ordinary shares for gross proceeds of $9.6 million. Offering costs in connection with both issuances were approximately $4.6 million.

At-the-Market Offering

In July 2019, the Company entered into an “at-the-market” sales agreement with Chardan Capital Markets, LLC, or Chardan, pursuant to which the Company may sell from time to time, ordinary shares having an aggregate offering price of up to $75.0 million through Chardan, acting as our agent. During the year ended December 31, 2020, the Company raised gross proceeds of $13.2 million, through the sale of 993,448 ordinary shares pursuant to an “at-the-market” equity offering program. Offering costs were approximately $0.5 million. In November 2020, the Company terminated the at-the-market equity program.

Acquisitions

In April 2020, the Company issued 522,000 ordinary shares in connection with the acquisition of Emrys.

In October 2020, the Company issued 22,500 ordinary shares, which represented the holdback shares from a previous acquisition.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

11. Income Taxes

For the years ended December 31, 2021 and 2020, the Company recognized a tax benefit of $0.

As of December 31, 2021, the Company had U.S. federal and state net operating losses (“NOLs”) and foreign carryforward tax losses which are available to reduce future taxable income of (in thousands):


	Federal		State/City
United Kingdom	$	164,288	$	—
United States	$	73,568	$	73,308
Other	$	35,296	$	—

The U.S. federal and state NOLs incurred prior to January 1, 2018 in the amount of approximately $6.8 million and $6.7 million, respectively, will begin to expire in 2036. The U.S. NOLs incurred after December 31, 2017 and the UK carryforward tax losses will be indefinitely carried forward. Also, as of December 31, 2021, the Company had orphan drug and research and development credits in the U.S. in the amount of $6.7 million which will begin to expire 2036 and research and development credits of $1.5 million in the UK which can be carried forward indefinitely. The U.S. NOLs and UK carryforward tax losses may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders, as defined under Section 382 Internal Revenue Code, as well as UK tax rules. This could limit the amount of NOLs and carryforward tax losses that the Company can utilize annually to offset future taxable income or tax liabilities. As of December 31, 2020, the Company had performed such an analysis and determined that there were no limitations in the UK. However, for U.S. purposes, the Company determined that a change of ownership occurred in April 2016 and again in June 2018. The Company is still in the process of determining the annual limitation on losses that occurred prior to June 2018.

The Company's pre-tax earnings are as follows (in thousands):


	December 31, 2021		December 31, 2020
United Kingdom	$	(17,056)	$	(41,373)
United States		(49,223)		(13,472)
Other		(13,282)		(3,147)
	$	(79,561)	$	(57,992)

The Company is subject to the corporate tax rate in the UK as a limited UK corporation.

The following table summarizes a reconciliation of income tax benefit compared with the amounts at the UK statutory income tax rate (in thousands):


	December 31, 2021			December 31, 2020
Statutory rate	(15,117)	19.00	%	(11,019)	19.00	%
Permanent differences - other	934	(1.17)	%	1,976	(3.41)	%
RTP and other adjustment	(2,735)	3.44	%	(2,136)	3.68	%
State and local rate, net of federal tax	(5,850)	7.35	%	(1,478)	2.55	%
U.K. tax credit	(1,464)	1.84	%	574	(0.99)	%
U.S. tax credit	(1,491)	1.87	%	(1,242)	2.14	%
Foreign tax rate differential	(540)	0.68	%	(254)	0.44	%
UK rate change (19% & 25% at expected DTA turn)	(10,247)	12.88	%	(2,234)	3.85	%
US state rate change	(447)	0.56	%	25	(0.04)	%
Change in valuation allowance	36,957	(46.45)	%	15,788	(27.22)	%
Actual income tax benefit effective tax rate	—	0.00	%	—	0.00	%

The Expense/(Benefit) for income taxes from continuing operations consists of the following (in thousands):


	December 31, 2021	December 31, 2020
Current Tax Expense/(Benefit)
United Kingdom	—	—
United States	—	—
Other	—	—
Total Current	—	—
Deferred Tax Expense/(Benefit)
United Kingdom	(16,079)	(9,197)
United States	(17,369)	(5,852)
Other	(3,509)	(739)
Total Deferred	(36,957)	(15,788)
Change in Valuation Allowance	36,957	15,788
Total Income Tax Expense/(Benefit)	—	—

Deferred Tax Assets/(Liabilities) (in thousands):


	December 31, 2021		December 31, 2020
Deferred Tax Assets:
Net operating loss carryforwards	$	74,007	$	43,831
Share-based compensation		10,314		5,392
R&D credit		7,498		5,819
Lease liability		7,040		6,150
Other		1,481		298
Deferred tax assets		100,340		61,490

Deferred Tax Liabilities:
Indefinite-lived intangibles		(196)		(173)
Depreciation		(3,339)		(2,252)
Right of use assets		(6,733)		(5,929)
Less: valuation allowance		(90,268)		(53,311)
Net deferred tax liability	$	(196)	$	(175)

ASC 740 requires a valuation allowance to reduce the deferred tax assets reported if, based on the weight of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. After consideration of all the evidence, both positive and negative, the Company has recorded a full valuation allowance, after consideration of the reversal of the deferred tax liabilities for the ROU assets and fixed assets, against its deferred tax assets at December 31, 2021 and 2020 because the Company's management has determined that is it more likely than not that these assets will not be fully realized.

Changes to the UK corporation tax rates have been announced which will impact future accounting periods. Finance Act 2021 increases the UK corporation tax rate from 19% to 25% effective April 1, 2023 for companies with profits in excess of GBP 250,000. As the Company does not expect to be able to utilize its carryforward tax losses in the UK until after April 2023, the deferred tax has been calculated using a tax rate of 25%.

As of December 31, 2021 and 2020, the Company recorded unrecognized tax positions of $0.7 and $0.5 million respectively. The unrecognized tax positions are netted with deferred tax assets above with full valuation allowance. The changes to unrecognized tax positions for 2021 and 2020 were as follows (in thousands):


	December 31, 2021		December 31, 2020
Unrecognized tax benefits as of January 1	$	513	$	—
Gross increases/(decreases) related to current year		165		138
Gross increases/(decreases) related to prior years		(12)		375
Foreign currency translation		—		—
Unrecognized tax positions as of December 31	$	666	$	513

The Company will recognize interest and penalties related to uncertain tax positions in income tax expense. As of December 31, 2021 and 2020, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company's statements of operations and comprehensive loss.

The Company files income tax returns in the United States, UK, various foreign jurisdictions and various U.S. state jurisdictions. In the U.S., all years remain subject to examination. The earliest year subject to the statute of limitations in the UK is 2019.

MeiraGTx Holdings plc is a UK tax resident with no earnings in its foreign subsidiaries and the Company does not expect any temporary basis difference in its investment in these subsidiaries to reverse in the foreseeable future. Therefore, the Company has not recorded deferred taxes on the outside basis difference in its foreign subsidiaries. It is not probable to compute the amounts, if any.

New Tax Legislation

Many governments have enacted or are currently contemplating economic stimulus and financial aid measures. Many of these measures include deferring the due dates for tax payments, including both income tax and other taxes. The Coronavirus Aid, Relief, and Economic Security Act ("CARES Act") was enacted on March 27, 2020 in the United States to address the economic impacts of the COVID-19 pandemic. The CARES Act includes corporate income tax, payroll tax, and other provisions. While the Company may receive financial, tax, or other benefits under the bill, this legislation did not impact the Company during the year ended December 31, 2021 and 2020.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Related Party Transactions

12 Months Ended

Dec. 31, 2021

Related Party Transactions

12. Related Party Transactions

Collaboration and License Agreements

Janssen Pharmaceuticals, Inc.

On January 30, 2019, the Company entered into a Collaboration Agreement with Janssen for the research, development and commercialization of gene therapies for the treatment of IRD. Under the agreement, Janssen paid the Company a non-refundable upfront fee of $100.0 million. Janssen and the Company will collaborate to develop the Company’s current clinical programs in retinitis pigmentosa and two genetic forms of achromatopsia and Janssen has the exclusive right to commercialize these three product candidates (“Clinical IRD Product Candidates”) globally.

Pursuant to the Collaboration Agreement, the Company and Janssen also agreed on a research collaboration to develop a pipeline of preclinical inherited retinal disease gene therapy candidates (“Research IRD Product Candidates”). The parties will select and prioritize the Research IRD Product Candidates and Janssen has the right to opt-in for a fee for each of the specified targets (each an “Option Target”) to obtain certain development, manufacturing and commercialization rights for the Research IRD Product Candidates.

Unless terminated earlier under certain termination clauses, the Collaboration Agreement will continue in effect, on a product-by-product and country-by-country basis, until such time as the royalty terms expire in such country. The Company has determined enforceable rights exist in the Collaboration Agreement as the termination clauses are substantive termination penalties by way of the non-refundable upfront fee and the reversion of any licensed intellectual property granted to Janssen upon the termination of the agreement.

On February 27, 2019, in connection with a private placement, the Company issued 2,898,550 ordinary shares to Johnson & Johnson Innovation – JJDC, Inc. (“JJDC”), the investment arm of Johnson & Johnson and owner of Janssen, on the same terms and conditions as the other investors in the offering. After the offering, JJDC became a related party.

Clinical IRD Product Candidates

Under the Collaboration Agreement, the Company and Janssen will jointly develop Clinical IRD Product Candidates to permit Janssen to commercialize such Clinical IRD Product Candidates under an exclusive license from the Company. In general, the Company will have the primary responsibility to develop each Clinical IRD Product Candidate in accordance with the development plan for each Clinical IRD Product Candidate, including where applicable, conducting any necessary research in order to submit the applicable regulatory filings to

regulatory authorities. The Company will manufacture these products in its cGMP manufacturing facilities for both clinical and commercial supply. Janssen will pay 100% of the clinical and commercialization costs of the products and the Company is eligible to receive untiered 20% royalties on net sales of products and additional development and commercialization milestones up to $340.0 million. The Company received its first milestone payment of $30.0 million in December 2021.

Research IRD Product Candidates

Under the Collaboration Agreement, the Company and Janssen will collaborate to develop Research IRD Product Candidates, with Janssen paying for the majority of the research costs. Janssen has the right to exclusively license any product coming out of the collaboration at the time of an investigational new drug application for an additional fee for each Research IRD Product Candidate. Janssen will then pay 100% of the clinical and commercialization costs for these Research IRD Product Candidates and the Company will receive an untiered royalty on net sales in the high teens as well as development milestones for each Research IRD Product Candidate.

Revenue Recognition under the Collaboration Agreement

The Collaboration Agreement is accounted for under ASC 808, however, ASC 808 does not address recognition or measurement matters. Therefore, the Company will account for the recognition and measurement of consideration under ASC 606. In determining the appropriate amount of revenue to be recognized under ASC 606, the Company performed the following steps: (i) identified the promised goods or services in the contract; (ii) determined whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. The Company evaluated the potential performance obligations in the contract, which included the exclusive license to Clinical IRD Product Candidates, the research, development and manufacturing services (“the services”), and the participation in various joint committees and determined that none of the performance obligations by themselves were distinct. Goods and services that are not distinct are bundled with other goods or services in the contract until a bundle of goods or services that is distinct is created. The services, when combined with the licenses, represent a bundle and should be accounted for as a single performance obligation due to the relevance of the services to the value of the early-stage license and the potential for the intellectual property to be significantly modified during the services period. The Company also evaluated whether or not the right to purchase exclusive option rights for specified Research IRD Product Candidates represents future performance obligations and concluded that these represent a separate buyer decision at market rates, rather than a material right performance obligation. As such, these options have been excluded from the initial allocation of transaction price and the Company will account for these options as separate contracts when and if Janssen elects to exercise the options.

Under ASC 606, the Company recognized collaboration revenue using the cost-to-cost input method, which it believes best depicts the transfer of control to the customer. Under the cost-to-cost input method, the extent of progress towards completion is measured based on the ratio of actual costs incurred to the total estimated costs expected upon satisfying the combined performance obligation by the potential product candidate. Under this method, revenue is being recorded as a percentage of the estimated transaction price based on the extent of progress towards completion. Under ASC 606, the estimated transaction price includes variable consideration subject to constraints. The Company does not include variable consideration to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will occur when any uncertainty associated with the variable consideration is resolved. The estimate of the Company’s measure of progress and estimate of variable consideration to be included in the transaction price will be updated at each reporting date as a change in estimate. The amount related to the unsatisfied portion will be recognized as that portion is satisfied over time.

Under ASC 606 the Company accounts for (i) the licenses it conveyed with respect to the Clinical IRD Product Candidates and (ii) its obligations to perform services as a single performance obligation under the Collaboration

Agreement with Janssen on a product candidate basis. Janssen’s right to purchase exclusive options to obtain certain development, manufacturing and commercialization rights are accounted for separately as they do not represent material rights, based on the criteria of ASC 606. Upon the exercise of any purchased option by Janssen, the contract promises associated with an Option Target would use a separate cost-to-cost model for purposes of revenue recognition under ASC 606.

During the year ended December 31, 2019, the Company received a $100.0 million non-refundable upfront fee from Janssen and during the year ended December 31, 2021, the Company received a $30.0 million milestone payment. The Company allocated these amounts plus other variable consideration not subject to constraint to each identified performance obligation using a combination of methods allowable under ASC 606. The Company applies the practical expedient in Topic 606 and does not include disclosures regarding amounts for variable consideration allocated to wholly-unsatisfied performance obligations or wholly-unsatisfied distinct goods that form part of a single performance obligation, if any. This variable consideration includes expected reimbursement of research and development costs.

During the years ended December 31, 2021 and 2020, the Company recognized $37.7 million and $15.6 million, respectively, of the deferred revenue – related party as license revenue.

The Company also recognized $69.0 million and $57.4 million during the years ended December 31, 2021 and 2020, respectively, related to the reimbursement of research and development expenses.

As of December 31, 2021, the Company expects to recognize the remaining $64.9 million in deferred revenue associated with the non-refundable upfront fee and milestone payment over the estimated research and development period using the cost-to-cost input method over an estimated period of approximately 3.5 years.

A summary of the deferred revenue recognition is as follows (in thousands):


Deferred revenue at December 31, 2019	$	86,214
Deferred revenue recognized as license revenue during the year ended December 31, 2020		(15,563)
Effects of exchange rate		2,191
Deferred revenue at December 31, 2020		72,842
Milestone payment from Janssen		30,000
Deferred revenue recognized as license revenue during the year ended December 31, 2021		(37,701)
Effects of exchange rate		(275)
Deferred revenue at December 31, 2021	$	64,866

Leases

ARE Lease

Effective July 1, 2016, the Company entered into a non-cancellable operating lease (the ”ARE Lease”) for laboratory and related office facilities in New York with ARE-East River Science Park, LLC (“ARE”), an entity that is under common control by an entity that is a minority shareholder of the Company and whose executive chairman and founder is a director of the Company. The ARE Lease provided for monthly base rent and property management fees, including rent escalations and rent holidays, plus operating expenses during the lease term, which was scheduled to expire on December 31, 2021. The Company recorded monthly rent expense on a straight-line basis from July 1, 2016 through February 29, 2020, the date the ARE Lease was terminated as described below.

On January 28, 2020, the Company and ARE mutually agreed to terminate the lease with no further obligation for either party effective as of February 29, 2020. Accordingly, the remaining right of use asset and operating lease

liability in the amount of $0.9 million and $1.0 million, respectively, was written off which resulted in a gain of $0.1 million.

Total rent expense under this operating lease was $0 and $0.1 million for the years ended December 31, 2021 and 2020, respectively.

ARE Vivarium Lease

Effective May 1, 2019, the Company entered into an operating lease for vivarium space with ARE, which was subsequently amended to add additional space within the vivarium. The initial lease had a term of twelve months which automatically renews on an annual basis.

The rent expense under this operating lease was $0.09 million and $0.02 million for the years ended December 31, 2021 and 2020, respectively, which are included in loss from operations.

The Company made cash payments to ARE in connection with this operating lease in the amount of $0.09 million and $0.02 million during the years ended December 31, 2021 and 2020, respectively.

There were no amounts due to ARE under this operating lease at December 31, 2021 and 2020.

As of December 31, 2021, the Company’s lease commitment is approximately $0.09 million.

Kadmon Lease

The Company leased office space on a month-to-month basis from Kadmon Corporation, LLC (“Kadmon”).

During the years ended December 31, 2021 and 2020, the Company incurred and paid rent charges from Kadmon in the amount of $0.5 million and $0.6 million, respectively, which are included in loss from operations.

This lease was terminated effective November 12, 2021.

Leases

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Leases

13. Leases

The Company has commitments under operating leases for laboratory, warehouse, clinical trial sites and office space. The Company also has finance leases for manufacturing space and office equipment. The Company’s leases have initial lease terms ranging from 3 years to 191 years. Certain lease agreements contain provisions for future rent increases. Payments due under the lease contracts include fixed payments.

Total rent expense recorded under these leases was $5.0 million and $3.3 million for the years ended December 31, 2021 and 2020, respectively.

On August 4, 2020, Meira Ireland entered into two agreements (the “Agreements”) with Shannon Commercial Enterprises DAC trading as Shannon Commercial Properties, to acquire two properties in the Shannon Free Zone in Shannon, Ireland for an aggregate price of €18 million, or approximately $21.2 million. These properties will serve as the Company’s second cGMP viral vector manufacturing facility and its first cGMP plasmid and DNA production facility.

The closing for the first building occurred in August 2020 and the closing for the second building occurred in January 2021. The total cost of the first and second buildings, including taxes and legal fees, was €11.9 million and €7.5 million, or approximately $13.8 million and $8.9 million, respectively, and have been recorded as right of use

assets in the consolidated balance sheets as of December 31, 2021. There is no corresponding lease liability as the Company paid the full cost on the date of the closings.

At the closings, Meira Ireland entered into a lease for each property providing for a long leasehold interest of approximately 191 years.

The leases also include customary terms and conditions, with a nominal annual lease cost and annual maintenance fees of approximately €0.3 million, or approximately $0.4 million, in the aggregate, which amount is subject to change depending on the annual maintenance costs within the Shannon Free Zone development.

During the year ended December 31, 2021, the Company recognized seven operating leases for locations in connection with its clinical trials for its IRD product candidates with initial lease terms between 5 years and 6 years. Certain lease agreements contain provisions for tenant allowances and future rent increases. Payments due under the lease contracts include fixed payments. In conjunction with these operating leases, the Company recognized initial operating lease right-of-use assets in the amount of $2.2 million and corresponding lease liabilities in the amount of $2.3 million which are included in the right-of-use assets and lease obligations in the consolidated balance sheets as of December 31, 2021.

The components of lease cost for the years ended December 31, 2021 and 2020 are as follows (in thousands):


	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	1,227	$	519
Interest on lease liabilities		2		3
Total finance lease cost		1,229		522
Operating lease cost		5,002		3,423
Short-term lease cost		751		714
Total lease cost	$	6,982	$	4,659

Amounts reported in the consolidated balance sheets for leases where the Company is the lessee as of December 31, 2021 and 2020 were as follows (in thousands):


	December 31,			December 31,
	2021			2020
Operating leases
Right-of-use asset	$	22,782		$	21,486
Capitalized lease obligations	$	23,721		$	22,221
Finance leases
Right-of-use asset	$	27,645		$	21,596
Capitalized lease obligations	$	12		$	28
Weighted-average remaining lease term
Operating leases		6.5	years		7.0	years
Finance leases		176.7	years		175.1	years
Weighted-average discount rate
Operating leases		8.5	%		8.6	%
Finance leases		8.0	%		8.0	%

Other information related to leases as of the years ended December 31, 2021 and 2020 are as follows (in thousands):


	2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	16	$	22
Operating cash flows from operating leases	$	4,969	$	3,791
Financing cash flows from finance leases	$	2	$	3

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	4,424	$	1,889
Finance leases	$	—	$	—

Future minimum lease payments under non-cancellable leases as of December 31, 2021 are as follows (in thousands):


	Operating Leases		Finance Leases
2022	$	5,252	$	13
2023		5,382		—
2024		5,223		—
2025		5,226		—
2026		4,996		—
Thereafter		4,251		—
Total undiscounted lease payments	$	30,330	$	13
Less: Imputed interest		(6,609)		(1)
Total lease liabilities	$	23,721	$	12

Commitments

12 Months Ended

Dec. 31, 2021

Commitments

Commitments

14. Commitments

License Agreement

Effective February 4, 2015, the Company entered into an exclusive worldwide license agreement with UCL Business, PLC (“UCL Business”) to develop up to eight programs using certain ocular gene therapy technology. Under the terms of the agreement, the Company had agreed to pay UCL Business certain sales milestone payments, if achieved, in the aggregate amount of £39.8 million, or approximately $53.7 million using the exchange rate at December 31, 2021, and royalties on net sales, as defined upon commercialization. Additionally, the Company is responsible for all patent prosecution and maintenance costs incurred and has also agreed to pay UCL Business an annual maintenance fee of £0.5 million, or approximately $0.07 million, until the first commercial sale of a product. The agreement terminates upon the later of (i) the last valid claim in a relevant product, (ii) the expiration of regulatory exclusivity to all licensed products, or (iii) the 10^th anniversary of the first commercial sale of a product.

On July 28, 2017, March 15, 2018 and September 7, 2018, the Company entered into additional exclusive worldwide license agreements with UCL Business under the same terms as the February 4, 2015 worldwide license agreement.

In January and February 2019, the Company amended and restated the following agreements: (i) the License Agreement, dated February 4, 2015, as amended, between the Company and UCL Business; (ii) the License Agreement, dated July 28, 2017, as amended, between the Company and UCL Business; and (iii) the License Agreement, dated March 15, 2018, between the Company and UCL Business to establish new stand-alone license

agreements for the following inherited retinal disease programs: (a) achromatopsia (“ACHM”) caused by mutations in CNGB3; (b) ACHM caused by mutations in CNGA3; (c) X-linked retinitis pigmentosa (“XLRP”); and (d) RPE65-mediated IRD.

The Company’s obligation to pay UCL Business a share of certain sublicensing revenues, as was provided under the February 4, 2015 agreement, has been removed from each of the stand-alone agreements with respect to the IRD programs listed above. Each of the stand-alone agreements now reflects terms substantially similar to those of the February 4, 2015 agreement.

Additionally, under the new stand-alone agreement related to CNGB3 the Company paid UCL Business an upfront payment of £1.5 million, or approximately $1.2 million, and issued 158,832 of the Company’s ordinary shares, which were valued at £1.5 million, or approximately $2.0 million.

Effective March 23, 2020, the Company entered into another worldwide license agreement with UCL Business, to develop an additional ocular gene therapy technology. Under the terms of the agreement, the Company agreed to pay UCL Business certain development and sales milestone payments, if achieved, in the aggregate amount of $39.25 million and royalties on net sales, as defined upon commercialization. Additionally, the Company is responsible for all patent prosecution and maintenance costs incurred and also agreed to pay UCL Business an upfront payment of $0.05 million and an annual maintenance fee of $0.03 million until the first commercial sale of a product. The agreement terminates upon the later of (i) the last valid claim in a relevant product, or (ii) the 10th anniversary of the first commercial sale of a product.

The Company incurred research and development expenses under the agreements in the amount of $0.4 million and $0.03 million during the years ended December 31, 2021 and 2020, respectively.

The amount due to UCL under the license agreements at December 31, 2021 and 2020 is $0.01 million and $0, and is included in accounts payable and accrued expenses on the consolidated balance sheets.

Employee Benefit Plans

12 Months Ended

Dec. 31, 2021

Postemployment Benefits [Abstract]

Employee Benefit Plans

15. Employee Benefit Plans

United States

On January 1, 2017, Meira LLC adopted a defined contribution retirement plan that complies with Section 401(k) of the Internal Revenue Code. All Meira LLC employees over the age of 21 are eligible to participate in the plan after three consecutive months of service. Employees are able to defer a portion of their pay into the plan on the first day of the month or after the day all age and service requirements have been met. The plan provides for a Company matching contribution. All eligible employees receive an employer matching contribution equal to the lesser of the amount the employee contributes to the plan or 6% of their salary up to the annual IRS limit.

United Kingdom

On August 1, 2016, Meira UK II adopted a defined contribution group personal pension plan that complies with HMRC for tax relief. All Meira UK II employees are eligible to participate in the plan upon joining the company and providing the required services. All eligible employees, if they elect to join the pension scheme, receive an employer pension contribution equal to 7.5% to 10.0% of their pensionable earnings. Currently, employees are required to contribute 0.5%, to meet minimum legal pension funding levels of 8%, but may make optional contributions up to the annual allowance HMRC limits.

Netherlands

Meira Netherlands operates a defined contribution pension. All of its employees participate in the plan. All eligible employees receive an employer pension contribution and are also required to contribute.

Ireland

On November 20, 2020, MeiraGTx Ireland adopted a defined contribution pension plan. All MeiraGTx Ireland employees are eligible to participate in the plan upon joining the Company. All eligible employees, if they elect to join the pension scheme, receive an employer pension contribution. The Company’s current contribution, exclusive of an employee match, is 4.5%, which exceeds Revenue Ireland requirements.

Belgium

Meira Belgium operates a defined contribution pension plan. All eligible employees receive an employer pension contribution of 8% of their annual salary. Employees do not make contributions to the plan.

During the years ended December 31, 2021 and 2020, employer contributions to all plans were $1.8 million and $1.1 million, respectively.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Consolidation

The accompanying consolidated financial statements include the accounts of Meira Holdings and its wholly owned subsidiaries:

MeiraGTx Limited, a limited company incorporated under the laws of England and Wales;

MeiraGTx, LLC, a Delaware limited liability company (“Meira LLC”);

MeiraGTx UK II Limited, a limited company incorporated under the laws of England and Wales (“Meira UK II”);

MeiraGTx Ireland DAC, a designated activity company incorporated under the laws of Ireland (“Meira Ireland”);

MeiraGTx Netherlands B.V., a private company with limited liability incorporated under the laws of the Netherlands (“Meira Netherlands”);

MeiraGTx Belgium, a private company with limited liability incorporated under the laws of Belgium (“Meira Belgium”);

BRI-Alzan, Inc., a Delaware corporation (“BRI-Alzan”);

MeiraGTx Bio Inc., a Delaware corporation (“Meira Bio”);

MeiraGTx B.V., a private company with limited liability incorporated under the laws of the Netherlands (“Meira B.V.”);

MeiraGTx Neurosciences, Inc., a Delaware corporation (“Meira Neuro”);

MeiraGTx Therapeutics, Inc., a Delaware corporation (“Meira Therapeutics”); and

MeiraGTx UK Limited, a limited company incorporated under the laws of England and Wales (“Meira UK”).

All intercompany balances and transactions between the consolidated companies have been eliminated in consolidation.

Use of Estimates

Cash and Cash Equivalents

Financial Instruments

Tax Incentive Receivable

Fair Value Measurements

●

Level 1: Observable inputs such as quoted prices in active markets for identical assets the reporting entity has the ability to access as of the measurement date;

●

Level 2: Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and

●

Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

The table below represents the values of the Company's financial assets and liabilities that are required to be measured at fair value on a recurring basis (in thousands):


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2021		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	66,585	$	66,585	$	—	$	—
Other long-term liabilities	$	953	$	953	$	—	$	—


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2020		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	186,938	$	186,938	$	—	0	—

Equity Method and Other Investments

Concentrations of Credit Risk

Intangible Assets

Intangible Assets

Property, Plant and Equipment, Net

The estimated useful lives of the asset categories are as follows:


Asset Category		Useful Lives
Computer and office equipment		3 years
Laboratory equipment		5 years
Manufacturing equipment		7 years
Furniture and fixtures		5 years
Leasehold improvements		lesser of useful life or remaining term of lease

Expenditures for leasehold improvements are capitalized, and expenditures for maintenance and repairs are expensed to operations as incurred.

Leases

Key estimates and judgments include how the Company determined (1) the discount rate used to discount the unpaid lease payments to present value, (2) lease term and (3) lease payments.

Asset Retirement Obligations

The change in asset retirement obligations is as follows (in thousands):


	For the Years Ended December 31,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Additional asset retirement obligations during the period		120		—
Amortization of interest		148		136
Effects of exchange rate		(1)		23
Balance at end of period	$	2,081	$	1,814

Share-Based Compensation Expense

Options

The fair value of ordinary shares after the Company’s IPO was determined based upon the closing share price on the date of grant.

Restricted Shares

Restricted Share Units

Collaboration Arrangements

Refer to the discussion in Note 12 for further information related to the accounting for the Collaboration Agreement.

Revenue Recognition

identify the contract(s) with a customer;

ii.

identify the performance obligations in the contract;

iii.

determine the transaction price;

iv.

allocate the transaction price to the performance obligations within the contract; and

recognize revenue when (or as) the entity satisfies a performance obligation.

The Company’s collaboration revenue arrangements include the following:

Research and Development

Foreign Currencies

Income Taxes

The Company is required to estimate income taxes in each of the jurisdictions in which it operates.

Net Loss per Ordinary Share


	December 31,	December 31,
	2021	2020
Share options	5,924,690	4,824,771
Restricted share units	1,415,000	545,000
Restricted ordinary shares subject to forfeiture	173,097	290,000
	7,512,787	5,659,771

Other Comprehensive Loss

Segment Information

Management has concluded it has a single reporting segment for purposes of reporting financial condition and results of operations.

The Company’s license revenue, research funding and deferred revenue from its Collaboration Agreement are generated in the United Kingdom.

The following table summarizes non-current assets by geographical area (in thousands):


	December 31,		December 31,
	2021		2020
United States	$	23,636	$	17,536
United Kingdom		43,349		44,487
European Union		69,936		29,098
	$	136,921	$	91,121

Recent Accounting Pronouncements Not Yet Adopted

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Schedule of Company's Financial Assets and Liabilities Measured at Fair Value

The table below represents the values of the Company's financial assets and liabilities that are required to be measured at fair value on a recurring basis (in thousands):


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2021		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	66,585	$	66,585	$	—	$	—
Other long-term liabilities	$	953	$	953	$	—	$	—


	Fair Value Measurement Using:
			Significant		Significant Other		Significant
	December 31,		Observable Inputs		Observable Inputs		Unobservable
Description	2020		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	186,938	$	186,938	$	—	0	—

Schedule of Estimated Useful Lives of Assets


Asset Category		Useful Lives
Computer and office equipment		3 years
Laboratory equipment		5 years
Manufacturing equipment		7 years
Furniture and fixtures		5 years
Leasehold improvements		lesser of useful life or remaining term of lease

Schedule of Change in Asset Retirement Obligations

The change in asset retirement obligations is as follows (in thousands):


	For the Years Ended December 31,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Additional asset retirement obligations during the period		120		—
Amortization of interest		148		136
Effects of exchange rate		(1)		23
Balance at end of period	$	2,081	$	1,814

Schedule of Anti-dilutive Securities Excluded from Computation of Earnings per Share


	December 31,	December 31,
	2021	2020
Share options	5,924,690	4,824,771
Restricted share units	1,415,000	545,000
Restricted ordinary shares subject to forfeiture	173,097	290,000
	7,512,787	5,659,771

Summary of Non-Current Assets by Geographical Area

The following table summarizes non-current assets by geographical area (in thousands):


	December 31,		December 31,
	2021		2020
United States	$	23,636	$	17,536
United Kingdom		43,349		44,487
European Union		69,936		29,098
	$	136,921	$	91,121

Equity Method and Other Investments (Tables)

12 Months Ended

Dec. 31, 2021

Long-term Investments [Abstract]

Schedule of Investments

The Company’s investments consist of the following (in thousands):


		December 31, 2021
Investee	Investment Type	Ownership Percentage		Carrying Value		Cost Basis
Visiogene LLC	Equity Method Investment	25	%	$	5,156	$	5,165
Other	Equity Investment	3	%		1,500		1,500
Total equity method and other investments				$	6,656	$	6,665

Prepaid Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Summary of Prepaid Expenses

Prepaid expenses at December 31, 2021 and 2020 consist of the following (in thousands):


	December 31,		December 31,
	2021		2020
Clinical trial costs	$	2,322	$	1,625
Insurance		2,122		2,903
Dues and license fees		1,185		515
Research and development		991		164
Manufacturing costs		624		1,395
Rent and facilities costs		455		169
Other		403		311
	$	8,102	$	7,082

Property, Plant and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment, net

Property, plant and equipment, net at December 31, 2021 and 2020 consist of the following (in thousands):


	December 31,		December 31,
	2021		2020
Leasehold improvements	$	60,878	$	33,777
Manufacturing equipment		12,156		7,021
Laboratory equipment		10,868		7,350
Computer and office equipment		5,750		3,713
Furniture and fixtures		687		568
		90,339		52,429
Less: Accumulated depreciation		(14,479)		(8,387)
	$	75,860	$	44,042

Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2021

Intangible Assets

Schedule of Intangible Assets

The following table presents the details of the Company’s intangible assets as of December 31, 2021 and 2020 (in thousands):


	December 31,		December 31,
	2021		2020
Licensed Technology	$	2,119	$	2,145
Less: Accumulated amortization		(328)		(26)
	$	1,791	$	2,119

Schedule of Amortization Expense

As of December 31, 2021, the expected amortization expense for the next five years and thereafter is as follows (in thousands):


	Amortization
	Expense
2022	$	306
2023		306
2024		306
2025		306
2026		306
Thereafter		261
Total amortization	$	1,791

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses at December 31, 2021 and 2020 were comprised of the following (in thousands):


	December 31,		December 31,
	2021		2020
Clinical trial costs	$	12,524	$	10,261
Compensation and benefits		6,029		3,791
Manufacturing costs		2,889		1,886
Fixed assets		2,077		949
Research and development		1,735		893
Professional fees		1,018		1,219
Consulting		858		1,047
Other		456		815
	$	27,586	$	20,861

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Company's Share Option Activity Related to Employees, Non-Employee Members of the Board of Directors and Non-Employee Consultants


					Weighted-
			Weighted-		Average
			Average		Remaining
		Number of	Exercise		Contractual
		Options	Price		Life (years)
Outstanding at December 31, 2019		3,645,360	$	9.31
Granted		1,666,500	$	15.91
Exercised		(109,296)	$	7.69
Expired		—	$	—
Forfeited		(377,793)	$	15.71
Outstanding at December 31, 2020		4,824,771	$	11.85	7.67	years
Granted		1,667,700	$	15.53
Exercised		(186,638)	$	9.16
Expired		—	$	—
Forfeited		(381,143)	$	12.22
Outstanding at December 31, 2021		5,924,690	$	13.16	7.40	years
Options exercisable at December 31, 2021		3,275,644	$	10.95	6.48	years
Aggregate intrinsic value of options outstanding as of December 31, 2021	$	62,702
Aggregate intrinsic value of options exercisable as of December 31, 2021	$	41,884

Schedule of Grant Date Fair Values of the Stock Options Granted


	2021	2020
Risk-free interest rate	0.62 - 1.39%	0.32 - 2.56%
Expected volatility	90%	90%
Expected dividend yield	0%	0%
Expected life (in years)	5.5 - 6.1	5.5 - 6.1

Summary of Company's RSU Activity Related to Employees, Non-Employee Members of the Board of Directors and Non-Employee Consultants


		Weighted-
	Number of	Average
	Restricted	Grant Date
	Share Units	Fair Value
Outstanding at December 31, 2019	—	$	—
Granted	545,000	$	20.02
Vested	—	$	—
Forfeited	—	$	—
Outstanding at December 31, 2020	545,000	$	20.02
Granted	870,000	$	15.36
Vested	—	$	—
Forfeited	—	$	—
Outstanding at December 31, 2021	1,415,000	$	17.16

Schedule of Share-Based Compensation Expense


	2021		2020
Research and development	$	9,685	$	6,026
General and administrative		11,099		12,391
Total share-based compensation	$	20,784	$	18,417

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Summary of Net Operating Loss Carryforwards


	Federal		State/City
United Kingdom	$	164,288	$	—
United States	$	73,568	$	73,308
Other	$	35,296	$	—

Schedule of Company's Pre-Tax Earnings

The Company's pre-tax earnings are as follows (in thousands):


	December 31, 2021		December 31, 2020
United Kingdom	$	(17,056)	$	(41,373)
United States		(49,223)		(13,472)
Other		(13,282)		(3,147)
	$	(79,561)	$	(57,992)

Schedule of Reconciliation of Income Tax Benefit with Amounts at the U.K. Statutory Income Tax Rate

The following table summarizes a reconciliation of income tax benefit compared with the amounts at the UK statutory income tax rate (in thousands):


	December 31, 2021			December 31, 2020
Statutory rate	(15,117)	19.00	%	(11,019)	19.00	%
Permanent differences - other	934	(1.17)	%	1,976	(3.41)	%
RTP and other adjustment	(2,735)	3.44	%	(2,136)	3.68	%
State and local rate, net of federal tax	(5,850)	7.35	%	(1,478)	2.55	%
U.K. tax credit	(1,464)	1.84	%	574	(0.99)	%
U.S. tax credit	(1,491)	1.87	%	(1,242)	2.14	%
Foreign tax rate differential	(540)	0.68	%	(254)	0.44	%
UK rate change (19% & 25% at expected DTA turn)	(10,247)	12.88	%	(2,234)	3.85	%
US state rate change	(447)	0.56	%	25	(0.04)	%
Change in valuation allowance	36,957	(46.45)	%	15,788	(27.22)	%
Actual income tax benefit effective tax rate	—	0.00	%	—	0.00	%

Schedule of Expense/(Benefit) for Income Taxes from Continuing Operations

The Expense/(Benefit) for income taxes from continuing operations consists of the following (in thousands):


	December 31, 2021	December 31, 2020
Current Tax Expense/(Benefit)
United Kingdom	—	—
United States	—	—
Other	—	—
Total Current	—	—
Deferred Tax Expense/(Benefit)
United Kingdom	(16,079)	(9,197)
United States	(17,369)	(5,852)
Other	(3,509)	(739)
Total Deferred	(36,957)	(15,788)
Change in Valuation Allowance	36,957	15,788
Total Income Tax Expense/(Benefit)	—	—

Schedule of Deferred Tax Assets and Liabilities

Deferred Tax Assets/(Liabilities) (in thousands):


	December 31, 2021		December 31, 2020
Deferred Tax Assets:
Net operating loss carryforwards	$	74,007	$	43,831
Share-based compensation		10,314		5,392
R&D credit		7,498		5,819
Lease liability		7,040		6,150
Other		1,481		298
Deferred tax assets		100,340		61,490

Deferred Tax Liabilities:
Indefinite-lived intangibles		(196)		(173)
Depreciation		(3,339)		(2,252)
Right of use assets		(6,733)		(5,929)
Less: valuation allowance		(90,268)		(53,311)
Net deferred tax liability	$	(196)	$	(175)

Schedule of Unrecognized Tax Benefits


	December 31, 2021		December 31, 2020
Unrecognized tax benefits as of January 1	$	513	$	—
Gross increases/(decreases) related to current year		165		138
Gross increases/(decreases) related to prior years		(12)		375
Foreign currency translation		—		—
Unrecognized tax positions as of December 31	$	666	$	513

Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2021

Summary of the Deferred Revenue Recognition

A summary of the deferred revenue recognition is as follows (in thousands):


Deferred revenue at December 31, 2019	$	86,214
Deferred revenue recognized as license revenue during the year ended December 31, 2020		(15,563)
Effects of exchange rate		2,191
Deferred revenue at December 31, 2020		72,842
Milestone payment from Janssen		30,000
Deferred revenue recognized as license revenue during the year ended December 31, 2021		(37,701)
Effects of exchange rate		(275)
Deferred revenue at December 31, 2021	$	64,866

Leases (Tables)

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Schedule of Components of Lease Cost

The components of lease cost for the years ended December 31, 2021 and 2020 are as follows (in thousands):


	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	1,227	$	519
Interest on lease liabilities		2		3
Total finance lease cost		1,229		522
Operating lease cost		5,002		3,423
Short-term lease cost		751		714
Total lease cost	$	6,982	$	4,659

Schedule of Consolidated Balance Sheets for Leases

Amounts reported in the consolidated balance sheets for leases where the Company is the lessee as of December 31, 2021 and 2020 were as follows (in thousands):


	December 31,			December 31,
	2021			2020
Operating leases
Right-of-use asset	$	22,782		$	21,486
Capitalized lease obligations	$	23,721		$	22,221
Finance leases
Right-of-use asset	$	27,645		$	21,596
Capitalized lease obligations	$	12		$	28
Weighted-average remaining lease term
Operating leases		6.5	years		7.0	years
Finance leases		176.7	years		175.1	years
Weighted-average discount rate
Operating leases		8.5	%		8.6	%
Finance leases		8.0	%		8.0	%

Schedule of Other Information Related to Leases

Other information related to leases as of the years ended December 31, 2021 and 2020 are as follows (in thousands):


	2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	16	$	22
Operating cash flows from operating leases	$	4,969	$	3,791
Financing cash flows from finance leases	$	2	$	3

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	4,424	$	1,889
Finance leases	$	—	$	—

Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases

Future minimum lease payments under non-cancellable leases as of December 31, 2021 are as follows (in thousands):


	Operating Leases		Finance Leases
2022	$	5,252	$	13
2023		5,382		—
2024		5,223		—
2025		5,226		—
2026		4,996		—
Thereafter		4,251		—
Total undiscounted lease payments	$	30,330	$	13
Less: Imputed interest		(6,609)		(1)
Total lease liabilities	$	23,721	$	12

Principal Business Activity - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Description Of Business [Line Items]
Accumulated deficit		$ (340,589)	$ (261,028)
Cash flows from operations		(10,530)	(63,967)
Cash, cash equivalents and restricted cash		$ 137,703	$ 209,520	$ 227,357
Minimum
Schedule Of Description Of Business [Line Items]
Offsetting expense, period		12 months
Janssen Pharmaceuticals Inc \| Collaboration Agreement
Schedule Of Description Of Business [Line Items]
Collaboration agreement upfront payment	$ 100,000
Milestone payments		$ 30,000
Janssen Pharmaceuticals Inc \| Collaboration Option And License Agreement
Schedule Of Description Of Business [Line Items]
Collaboration agreement upfront payment				$ 100,000

Summary of Significant Accounting Policies - Tax Incentive Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Tax incentive receivable	$ 12,634	$ 12,930
Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Tax incentive receivable	5,400	5,300
VAT receivable	$ 1,900	$ 4,000

Summary of Significant Accounting Policies - Company's Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Other long-term liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, net asset (liability)	$ 953
Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, net asset (liability)	66,585	$ 186,938
Fair Value, Inputs, Level 1 [Member] \| Other long-term liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, net asset (liability)	953
Fair Value, Inputs, Level 1 [Member] \| Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, net asset (liability)	$ 66,585	$ 186,938

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Assets (Details)	12 Months Ended
	Dec. 31, 2021
Computer Equipment And Software [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life (years)	3 years
Laboratory Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life (years)	5 years
Manufacturing Equipment [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life (years)	7 years
Furniture & Fixtures [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life (years)	5 years
Leasehold Improvements [Member]
Depreciation Amortization Impairment [Line Items]
Estimated useful life (years)	lesser of useful life or remaining term of lease

Summary of Significant Accounting Policies - Schedule of Change in Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Asset Retirement Obligation [Abstract]
Balance at beginning of period	$ 1,814	$ 1,655
Additional asset retirement obligations during the period	120
Amortization of interest	148	136
Effects of exchange rate	(1)	23
Balance at end of period	$ 2,081	$ 1,814

Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings per Share (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	7,512,787	5,659,771
Share Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	5,924,690	4,824,771
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	1,415,000	545,000
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	173,097	290,000

Summary of Significant Accounting Policies - Summary of Non-Current Assets by Geographical Area (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Operation By Geographical [Line Items]
Non-current assets	$ 136,921	$ 91,121
United States
Operation By Geographical [Line Items]
Non-current assets	23,636	17,536
United Kingdom
Operation By Geographical [Line Items]
Non-current assets	43,349	44,487
European Union
Operation By Geographical [Line Items]
Non-current assets	$ 69,936	$ 29,098

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Impairment charges	$ 0	$ 0
Unrecognized tax positions	666	513
Unrecognized tax benefits, income tax penalties and interest accrued	$ 0	$ 0
Licensed Technology
Amortization period	7 years
Measurement Input, Risk Free Interest Rate [Member]
Credit-adjusted risk-free rate	8

Acquisitions - Bullseye (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Oct. 04, 2021	Apr. 09, 2020	Dec. 31, 2021	Dec. 31, 2020
Acquisition
Fair value of asset acquisition in process R&D		$ 7,700
Assumed liabilities			$ 134,763	$ 125,138
Research and development expenses			67,128	$ 33,910
Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Total consideration	$ 1,500
Fair value of asset acquisition in process R&D	1,500
Assumed liabilities	$ 500		1,000
Research and development expenses			$ 500
Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Number of shares issued	80,276
Share price	$ 13.31		$ 23.74
On Closing Date [Member] \| Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Number of shares issued	12,040
On Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Number of shares issued	28,097
Following Closing Date [Member] \| Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Number of shares issued	40,139
Term of issue of shares	18 months
First Anniversary Of Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Vesting percentage	50.00%
Second Anniversary Of Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Acquisition
Vesting percentage	50.00%

Acquisitions - Emrys Bio Inc. (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 09, 2021	Apr. 09, 2020
Acquisition
Fair value of asset acquisition in process R&D		$ 7.7
Acquisition Of Emrys [Member]
Acquisition
Total consideration		$ 7.7
Ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Number of shares issued		580,000
Share price		$ 13.25
On Closing Date [Member] \| Ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Number of shares issued	58,000	232,000
On Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Number of shares issued		290,000
Following Closing Date [Member] \| Ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Number of shares issued		58,000
Term of issue of shares		18 months
First Anniversary Of Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Vesting percentage		50.00%
Second Anniversary Of Closing Date [Member] \| Restricted ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Acquisition
Vesting percentage		50.00%

Equity Method and Other Investments - Summary of Investments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Ownership Percentage, other investments	3.00%
Carrying Value and cost other investments	$ 1,500
Total equity method and other investments	6,665
Total equity method and other investments	$ 6,656
Visiogene LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Carrying Value	$ 5,156
Cost Basis	$ 5,165

Equity Method and Other Investments (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 04, 2021	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Research and development		$ 67,128	$ 33,910
Visiogene License Agreement
Schedule of Equity Method Investments [Line Items]
Ordinary shares issued in connection with a license agreement (in shares)	75,000
Value of shares issued	$ 1,200	1,165
Visiogene LLC
Schedule of Equity Method Investments [Line Items]
Number of preferred units acquired	3,000,000
Cash consideration	$ 5,000
Ordinary shares issued in connection with a license agreement (in shares)	75,000
Value of shares issued	$ 1,200
Research and development		$ 10
Visiogene LLC \| Visiogene License Agreement
Schedule of Equity Method Investments [Line Items]
Allocation of payments	1,000
Investment allocated amount expensed	1,000
Visiogene LLC \| Visiogene Unit Agreement
Schedule of Equity Method Investments [Line Items]
Allocation of payments	$ 5,200

Prepaid Expenses - Summary of Prepaid Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Clinical trial costs	$ 2,322	$ 1,625
Insurance	2,122	2,903
Dues and license fees	1,185	515
Research and development	991	164
Manufacturing costs	624	1,395
Rent and facilities costs	455	169
Other	403	311
Total	$ 8,102	$ 7,082

Property, Plant and Equipment, net - Schedule of Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 90,339	$ 52,429
Less: Accumulated depreciation	(14,479)	(8,387)
Property, plant and equipment, net	75,860	44,042
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	60,878	33,777
Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	12,156	7,021
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	10,868	7,350
Computer and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,750	3,713
Furniture & Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 687	$ 568

Property, Plant and Equipment, net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Property, Plant and Equipment [Line Items]
Asset retirement obligations, discounted rate	8.00%
Asset retirement obligations	$ 2,081	$ 1,814	$ 1,655	$ 4,100
Depreciation expense	6,300	$ 3,700
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Asset retirement obligations	$ 1,900

Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Nov. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Total	$ 1,791
Licensed Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,119	$ 2,145	$ 2,100
Less: Accumulated Amortization	(328)	(26)
Total	$ 1,791	$ 2,119

Intangible Assets - Asset Transaction (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Intangible Assets
Amortization expense	$ 300	$ 20

Intangible Assets - Amortization Expense (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Amortization expense
2022	$ 306
2023	306
2024	306
2025	306
2026	306
Thereafter	261
Total	$ 1,791

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Clinical trial costs	$ 12,524	$ 10,261
Compensation and benefits	6,029	3,791
Manufacturing costs	2,889	1,886
Fixed assets	2,077	949
Research and development	1,735	893
Professional fees	1,018	1,219
Consulting	858	1,047
Other	456	815
Accrued expenses	$ 27,586	$ 20,861

Share-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Jun. 07, 2018 item $ / shares shares	Jan. 31, 2022 shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance \| shares			7,388,448		3,054,996
Additional shares reserved for issuance \| shares		1,778,500
Shares available for future issuance \| shares			1,195,477
Number of options, Granted \| shares			1,667,700	1,666,500
Weighted-average remaining contractual life of options, outstanding			7 years 4 months 24 days	7 years 8 months 1 day
Fair value of options, Vested			$ 14,400	$ 8,200
Weighted-average grant date fair value of options granted \| $ / shares			$ 11.44	$ 11.87
Share-based compensation			$ 20,784	$ 18,417
Total share-based compensation			20,784	18,417
Excess tax benefits, operating activities			$ 0	0
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual life of options, outstanding			10 years
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			$ 11,099	12,391
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			$ 9,685	$ 6,026
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted share units, Granted \| shares			870,000	545,000
Period expected to realize unrecognized compensation expense			3 years 8 months 12 days
Total compensation expense not yet recognized relating to unvested RSUs			$ 15,600
Ordinary shares \| shares			870,000	545,000
Total share-based compensation			$ 6,000	$ 2,600
Restricted Stock Units (RSUs) \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			4,900	2,500
Restricted Stock Units (RSUs) \| Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			1,100	100
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unvested options compensation expense not yet recognized			$ 26,100
Period expected to realize unrecognized compensation expense			4 years
Total share-based compensation			$ 14,800	12,900
Share Options \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			6,200	7,000
Share Options \| Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation			$ 8,600	5,900
Senior Management [Member] \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted share units, Granted \| shares	1,306,348
Vesting percentage	33.33%
Ordinary shares awarded, per share \| $ / shares	$ 15.00
Ordinary shares \| shares	1,306,348
Fully-diluted outstanding shares	5.00%
Number of quarters for vesting \| item	8
Share-based compensation				6,500
Total share-based compensation				2,900
Senior Management [Member] \| Restricted Shares \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation				$ 3,600
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			36 months
certain executives, employees and consultants \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted share units, Granted \| shares		2,186,200
Ordinary shares \| shares		2,186,200
certain executives, employees and consultants \| Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, Granted \| shares		2,186,200
First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			25.00%
Second Anniversary [Member] \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
Third Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			25.00%
Fourth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			25.00%
Over Three Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			36 months

Share-Based Compensation - Summary of Company's Share Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Number of Options
Number of options, Beginning balance	4,824,771	3,645,360
Number of options, Granted	1,667,700	1,666,500
Number of options, Exercised	(186,638)	(109,296)
Number of options, Expired		0
Number of options, Forfeited	(381,143)	(377,793)
Number of options, Ending balance	5,924,690	4,824,771
Weighted-Average Exercise Price
Weighted-average exercise price, Beginning balance	$ 11.85	$ 9.31
Weighted-average exercise price, Granted	15.53	15.91
Weighted-average exercise price, Exercised	9.16	7.69
Weighted-average exercise price, Expired		0
Weighted-average exercise price, Forfeited	12.22	15.71
Weighted-average exercise price, Ending balance	$ 13.16	$ 11.85
Options additional disclosures
Number of options, Options exercisable	3,275,644
Weighted-average exercise price, Options exercisable	$ 10.95
Weighted-average remaining contractual life of options, outstanding	7 years 4 months 24 days	7 years 8 months 1 day
Weighted-average remaining contractual life of options, exercisable	6 years 5 months 23 days
Aggregate intrinsic value, options outstanding	$ 62,702
Aggregate intrinsic value, options exercisable	$ 41,884

Share-Based Compensation - Schedule of Grant Date Fair Values of the Share Options Granted Black-Scholes Valuation Model (Details) - Share Options	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	0.62%	0.32%
Risk-free interest rate, maximum	1.39%	2.56%
Expected volatility	90.00%	90.00%
Expected dividend yield	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	5 years 6 months	5 years 6 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	6 years 1 month 6 days	6 years 1 month 6 days

Share-Based Compensation - Summary of Restricted Share Units (Details) - Restricted Stock Units (RSUs) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Number of restricted share units
Number of restricted share units, Beginning balance	545,000
Number of restricted share units, Granted	870,000	545,000
Number of restricted share units, Ending balance	1,415,000	545,000
Weighted-average grant date fair value
Weighted-average grant date fair value, Beginning balance	$ 20.02
Weighted-average grant date fair value, Granted	15.36	$ 20.02
Weighted-average grant date fair value, Ending balance	$ 17.16	$ 20.02

Share-Based Compensation - Schedule of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Expense [Line Items]
Total share-based compensation	$ 20,784	$ 18,417
General and Administrative Expense [Member]
Share Based Compensation Expense [Line Items]
Total share-based compensation	11,099	12,391
Research and Development Expenses [Member]
Share Based Compensation Expense [Line Items]
Total share-based compensation	$ 9,685	$ 6,026

Ordinary Shares - Additional Information (Details) - USD ($) $ in Thousands					1 Months Ended			2 Months Ended	10 Months Ended	12 Months Ended
	Oct. 09, 2021	Oct. 04, 2021	Jan. 04, 2021	Apr. 09, 2020	Dec. 31, 2020	Nov. 30, 2020	Jul. 31, 2019	Dec. 31, 2020	Oct. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Apr. 30, 2020	Feb. 27, 2019
Common stock, shares issued					44,189,150			44,189,150		44,548,925	44,189,150
Proceeds from the issuance of ordinary shares											$ 87,051
Offering costs											$ 5,141
Visiogene License Agreement
Ordinary shares issued in connection with a license agreement (in shares)			75,000
Issuance of shares in connection with a license agreement			$ 1,200							$ 1,165
Ordinary Shares [Member]
Common stock, shares issued									22,500
Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member]
Number of shares issued		80,276
Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member] \| On Closing Date [Member]
Number of shares issued		12,040
Ordinary Shares [Member] \| Acquisition of Bullseye Therapeutics Inc [Member] \| Following Closing Date [Member]
Number of shares issued		40,139
Ordinary Shares [Member] \| Acquisition Of Emrys [Member]
Number of shares issued				580,000
Common stock, shares issued												522,000
Ordinary Shares [Member] \| Acquisition Of Emrys [Member] \| On Closing Date [Member]
Number of shares issued	58,000			232,000
Ordinary Shares [Member] \| Acquisition Of Emrys [Member] \| Following Closing Date [Member]
Number of shares issued				58,000
Over-Allotment Option [Member]
Common stock, shares issued					750,000	5,000,000		750,000			750,000
Proceeds from the issuance of ordinary shares					$ 9,600	$ 64,300
Offering costs								$ 4,600
At-the-market offering [Member]
Offering costs									$ 500
Aggregate offer price							$ 75,000
Proceeds from issuance of private placement											$ 13,200
Number of ordinary shares sold											993,448
JJDC \| Private Placement [Member]
Common stock, shares issued													2,898,550

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2017
Income Taxes Disclosure [Line Items]
Federal net operating loss carryforwards			$ 6,800
State net operating loss carryforwards			$ 6,700
Deferred tax assets, tax credit carryforwards	$ 7,498	$ 5,819
Unrecognized tax positions	666	513
Unrecognized tax benefits, income tax penalties and interest accrued	0	0
Income tax expense (benefit)	$ 0	$ 0
Her Majesty's Revenue and Customs (HMRC) [Member]
Income Taxes Disclosure [Line Items]
Tax rate	25.00%
United Kingdom \| Federal [Member]
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards	$ 164,288
United Kingdom \| Her Majesty's Revenue and Customs (HMRC) [Member] \| Research Tax Credit Carryforward
Income Taxes Disclosure [Line Items]
Deferred tax assets, tax credit carryforwards	1,500
United States \| Federal [Member]
Income Taxes Disclosure [Line Items]
Deferred tax assets, tax credit carryforwards	6,700
Net operating loss carryforwards	73,568
Other \| Federal [Member]
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards	$ 35,296

Income Taxes - Net Operating Loss Carryforwards (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Federal [Member] \| United Kingdom
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 164,288
Federal [Member] \| United States
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	73,568
State [Member] \| United States
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 73,308

Income Taxes - Summary of Company's Pre-Tax Earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Before Income Taxes [Line Items]
Total	$ (79,561)	$ (57,992)
U.K. [Member] \| Her Majesty's Revenue and Customs (HMRC) [Member] \| United Kingdom
Income Before Income Taxes [Line Items]
Total	(17,056)	(41,373)
Federal [Member] \| Internal Revenue Service (IRS) [Member] \| United States
Income Before Income Taxes [Line Items]
Total	(49,223)	(13,472)
Other Countries Jurisdiction [Member] \| Internal Revenue Service (IRS) [Member] \| Other
Income Before Income Taxes [Line Items]
Total	$ (13,282)	$ (3,147)

Income Taxes - Summary of Reconciliation of Income Tax Benefit with Amounts at the U.K. Statutory Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Change in valuation allowance	$ 36,957	$ 15,788
Total Income Tax Expense (Benefit)	0	0
Her Majesty's Revenue and Customs (HMRC) [Member]
Statutory rate	(15,117)	(11,019)
Permanent differences - other	934	1,976
RTP and other adjustments	(2,735)	(2,136)
State and local rate, net of federal tax	(5,850)	(1,478)
U.K. tax credit	(1,464)	574
U.S. tax credit	(1,491)	(1,242)
Foreign tax rate differential	(540)	(254)
UK rate change (19% & 25% at expected DTA turn)	(10,247)	(2,234)
US state rate change	(447)	25
Change in valuation allowance	$ 36,957	$ 15,788
Tax rate	19.00%	19.00%
Permanent differences - other	(1.17%)	(3.41%)
RTP and other adjustments	3.44%	3.68%
State and local rate, net of federal tax	7.35%	2.55%
U.K. tax credit	1.84%	(0.99%)
U.S. tax credit	1.87%	2.14%
Foreign tax rate differential	0.68%	0.44%
UK rate change (19% & 25% at expected DTA turn)	12.88%	3.85%
US state rate change	0.56%	(0.04%)
Change in valuation allowance	(46.45%)	(27.22%)
Actual income tax benefit effective tax rate	0.00%	0.00%
Her Majesty's Revenue and Customs (HMRC) [Member] \| Tax Year 2020
Tax rate		25.00%

Income Taxes - Schedule of Expense (Benefit) for Income Taxes from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Expense/(Benefit)
Total Deferred	$ (36,957)	$ (15,788)
Change in Valuation Allowance	36,957	15,788
Total Income Tax Expense (Benefit)	0	0
United Kingdom
Deferred Tax Expense/(Benefit)
Foreign	(16,079)	(9,197)
United States
Deferred Tax Expense/(Benefit)
United States	(17,369)	(5,852)
Other
Deferred Tax Expense/(Benefit)
Foreign	$ (3,509)	$ (739)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets:
Net operating loss carryforwards	$ 74,007	$ 43,831
Share-based compensation	10,314	5,392
R&D credit	7,498	5,819
Lease liability	7,040	6,150
Other	1,481	298
Deferred tax assets	100,340	61,490
Deferred Tax Liabilities:
Indefinite-lived intangibles	(196)	(173)
Depreciation	(3,339)	(2,252)
Right of use assets	(6,733)	(5,929)
Less: valuation allowance	(90,268)	(53,311)
Net deferred tax liability	(196)	$ (175)
Federal [Member] \| United States
Deferred Tax Assets:
R&D credit	$ 6,700

Income Taxes - Summary of Unrecognized Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Uncertainties [Abstract]
Unrecognized tax benefits, beginning balance	$ 513
Gross increases/(decreases) related to current year	165	$ 138
Gross increases related to prior years		375
Gross (decreases) related to prior years	(12)
Unrecognized tax benefits, ending balance	$ 666	$ 513

Related Party Transactions - Collaboration and License Agreements (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Mar. 31, 2019	Jan. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 27, 2019
Related Party Transaction [Line Items]
Shares issued to related party			44,548,925	44,189,150
Clinical IRD Product Candidate development
Related Party Transaction [Line Items]
Milestone payments			$ 30,000
Clinical IRD Product Candidate development \| Maximum
Related Party Transaction [Line Items]
Additional development and commercialization milestones		$ 340,000
Clinical IRD Product Candidate development \| Collaboration Agreement
Related Party Transaction [Line Items]
Royalties receivable, as a percentage		20.00%
JJDC \| Private Placement [Member]
Related Party Transaction [Line Items]
Shares issued to related party						2,898,550
Janssen Pharmaceuticals Inc \| Collaboration Agreement
Related Party Transaction [Line Items]
Collaboration agreement upfront payment	$ 100,000
Milestone payments			30,000
Deferred revenue - related party recognized as license revenue			37,701	$ 15,563
Reimbursement of research and development expenses			$ 69,000	$ 57,400
Janssen Pharmaceuticals Inc \| Collaboration Option And License Agreement
Related Party Transaction [Line Items]
Collaboration agreement upfront payment					$ 100,000
Janssen Pharmaceuticals Inc \| Research, development and commercialization of gene therapies \| Collaboration Option And License Agreement
Related Party Transaction [Line Items]
Collaboration agreement upfront payment		$ 100,000
Janssen Pharmaceuticals Inc \| Clinical IRD Product Candidate development \| Collaboration Agreement
Related Party Transaction [Line Items]
Percentage of costs payable on annual net sales of licensed product statement		100.00%
Janssen Pharmaceuticals Inc \| Research IRD Candidates development \| Collaboration Agreement
Related Party Transaction [Line Items]
Percentage of clinical and commercialization costs to be paid by related party		100.00%

Related Party Transactions - Performance Obligation (Details) - Collaboration Agreement - Janssen Pharmaceuticals Inc - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 $ in Millions	Dec. 31, 2021 USD ($)
Related Party Transaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 64.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 years 6 months

Related Party Transactions - Revenue Recognition (Details) - Janssen Pharmaceuticals Inc - Collaboration Agreement - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Deferred revenue at the beginning	$ 72,842	$ 86,214
Milestone payments	30,000
Deferred revenue recognized as license revenue during period	(37,701)	(15,563)
Effects of exchange rate	(275)	2,191
Deferred revenue at the end	$ 64,866	$ 72,842

Related Party Transactions - License Agreement (Details) $ in Thousands, £ in Millions						12 Months Ended
	Mar. 23, 2020 USD ($)	Mar. 15, 2018 USD ($) shares	Mar. 15, 2018 GBP (£) shares	Feb. 04, 2015 USD ($) item	Feb. 04, 2015 GBP (£) item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Related Party Transaction [Line Items]
Research and development expenses						$ 67,128	$ 33,910
License Agreement [Member]
Related Party Transaction [Line Items]
Amount due under services agreement						10	0
Research and development expenses						400	$ 30
UCL Business, PLC [Member] \| License Agreement [Member]
Related Party Transaction [Line Items]
Number of collaborations programs \| item				8	8
Aggregate sales milestone payments payable					£ 39.8	$ 53,700
Maintenance fee				$ 70	£ 0.5
License arrangement upfront payment	$ 50
Development and sales milestone payments	39,250
Patent prosecution and maintenance costs	$ 30
UCL Business, PLC [Member] \| License Agreement For Inherited Retinal Disease Programs Related To CNGB3 [Member]
Related Party Transaction [Line Items]
License arrangement upfront payment		$ 1,200	£ 1.5
Ordinary shares issued in connection with a license agreement (in shares) \| shares		158,832	158,832
Issuance of shares in connection with a license agreement		$ 2,000	£ 1.5

Related Party Transactions - Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Operating lease rent expenses	$ 5,000	$ 3,300
Cash paid	4,969	3,791
ARE East River Science Park LLC [Member]
Related Party Transaction [Line Items]
Operating lease, right of use asset write-off	900
Operating lease liability write-off	1,000
Net gain on write-off of operating lease right of use asset and liability	100
Operating lease rent expenses	$ 0	100
ARE East River Science Park LLC [Member] \| Vivarium Space Operating Lease
Related Party Transaction [Line Items]
Operating lease, term of contract	12 months
Cash paid	$ 90	20
Amount due	0	0
Lease commitment	90
ARE East River Science Park LLC [Member] \| Vivarium Space Operating Lease \| Loss from operations
Related Party Transaction [Line Items]
Operating lease rent expenses	90	20
Kadmon Corporation LLC [Member] \| Loss from operations
Related Party Transaction [Line Items]
Operating lease rent expenses	$ 500	$ 600

Leases - Additional Information (Details) $ in Thousands, € in Millions			12 Months Ended
	Aug. 04, 2020 USD ($) property contract	Aug. 04, 2020 EUR (€) property contract	Dec. 31, 2021 USD ($) lease	Dec. 31, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2021 EUR (€) lease
Lessee, Lease, Description [Line Items]
Operating lease rent expenses			$ 5,000		$ 3,300
Annual lease cost and annual maintenance fees			400	€ 0.3
Right-of-use asset			22,782		21,486
Operating lease liability			$ 23,721		22,221
Building one
Lessee, Lease, Description [Line Items]
Capitalized building costs					13,800	€ 11.9
Building two
Lessee, Lease, Description [Line Items]
Capitalized building costs					$ 8,900	€ 7.5
Janssen Pharmaceuticals Inc
Lessee, Lease, Description [Line Items]
Number of operating leases \| lease			7			7
Right-of-use asset			$ 2,200
Operating lease liability			$ 2,300
Shannon Free Zone [Member]
Lessee, Lease, Description [Line Items]
Number of agreements \| contract	2	2
Number of properties \| property	2	2
Purchase price consideration	$ 21,200	€ 18.0
Minimum
Lessee, Lease, Description [Line Items]
Lease term			3 years	3 years
Minimum \| Janssen Pharmaceuticals Inc
Lessee, Lease, Description [Line Items]
Operating lease, term of contract			5 years			5 years
Maximum
Lessee, Lease, Description [Line Items]
Lease term			191 years	191 years
Maximum \| Janssen Pharmaceuticals Inc
Lessee, Lease, Description [Line Items]
Operating lease, term of contract			6 years			6 years

Leases - Schedule of Components of Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Amortization of right-of-use assets	$ 1,227	$ 519
Interest on lease liabilities	2	3
Total finance lease cost	1,229	522
Operating lease cost	5,002	3,423
Short-term lease cost	751	714
Total lease cost	$ 6,982	$ 4,659

Leases - Schedule of Consolidated Balance Sheets for Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Operating leases
Right-of-use asset	$ 22,782	$ 21,486
Capitalized lease obligations	$ 23,721	$ 22,221
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Liabilities	Liabilities
Finance leases
Right-of-use asset	$ 27,645	$ 21,596
Capitalized lease obligations	$ 12	$ 28
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Liabilities	Liabilities
Weighted-average remaining lease term
Operating leases	6 years 6 months	7 years
Finance leases	176 years 8 months 12 days	175 years 1 month 6 days
Weighted-average discount rate
Operating leases	8.50%	8.60%
Finance leases	8.00%	8.00%

Leases - Schedule of Other Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$ 16	$ 22
Operating cash flows from operating leases	4,969	3,791
Financing cash flows from finance leases	2	3
Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$ 4,424	$ 1,889

Leases - Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Operating Leases
2022	$ 5,252
2023	5,382
2024	5,223
2025	5,226
2026	4,996
Thereafter	4,251
Total undiscounted lease payments	30,330
Less: Imputed interest	(6,609)
Operating lease liability	23,721	$ 22,221
Finance Leases
2022	13
Total undiscounted lease payments	13
Less: Imputed interest	(1)
Finance lease liability	$ 12	$ 28

Commitments - License Agreement (Details) $ in Thousands, £ in Millions						12 Months Ended
	Mar. 23, 2020 USD ($)	Mar. 15, 2018 USD ($) shares	Mar. 15, 2018 GBP (£) shares	Feb. 04, 2015 USD ($) item	Feb. 04, 2015 GBP (£) item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Other Commitments [Line Items]
Research and development expenses						$ 67,128	$ 33,910
License Agreement [Member]
Other Commitments [Line Items]
Amount due under services agreement						10	0
Research and development expenses						400	$ 30
UCL Business, PLC [Member] \| License Agreement [Member]
Other Commitments [Line Items]
Number of collaborations programs \| item				8	8
Aggregate sales milestone payments payable					£ 39.8	$ 53,700
Maintenance fee				$ 70	£ 0.5
License arrangement upfront payment	$ 50
Development and sales milestone payments	39,250
Patent prosecution and maintenance costs	$ 30
UCL Business, PLC [Member] \| License Agreement For Inherited Retinal Disease Programs Related To CNGB3 [Member]
Other Commitments [Line Items]
License arrangement upfront payment		$ 1,200	£ 1.5
Ordinary shares issued in connection with a license agreement (in shares) \| shares		158,832	158,832
Issuance of shares in connection with a license agreement		$ 2,000	£ 1.5

Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Millions			12 Months Ended
	Jan. 01, 2017	Aug. 01, 2016	Dec. 31, 2021	Dec. 31, 2020
Compensation And Retirement Disclosure [Line Items]
Defined benefit plan, plan assets, contributions by employer			$ 1.8	$ 1.1
United States
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, annual contributions per employee, percent	6.00%
United States \| Minimum
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, employee eligibility age	21 years
United Kingdom [Member]
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, annual contributions per employee, percent		0.50%
United Kingdom [Member] \| Minimum
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, employer matching contribution, percent		7.50%
United Kingdom [Member] \| Maximum
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, employer matching contribution, percent		10.00%
Ireland
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, employer contribution exclusive of employee match, percent			4.50%
Belgium
Compensation And Retirement Disclosure [Line Items]
Defined contribution plan, employer contribution exclusive of employee match, percent			8.00%