0001558370-21-011229 | 10-Q | XBRL Viewer

Organization and Basis of Presentation

1. Organization and Basis of Presentation:

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: inherited retinal 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, which includes fill and finish capabilities and can supply the Company’s clinical and potential commercial material. Additionally, the Company expanded its manufacturing and supply chain capabilities by acquiring a second cGMP viral vector manufacturing facility and its first cGMP plasmid and DNA production facility in Shannon, Ireland. The Company completed the acquisition of these facilities in January 2021.

Basis of Presentation

The accompanying condensed 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”).

Interim Financial Statements

The accompanying condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP for complete consolidated financial statements. In the opinion of management, the condensed consolidated financial statements include all adjustments (consisting of normal recurring accruals) necessary in order to make the condensed consolidated financial statements not misleading. Operating results for the six-month period ended June 30, 2021 are not necessarily indicative of the final results that may be expected for the year ending December 31, 2021. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2020 included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 (the “Form 10-K”).

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 June 30, 2021 totaled $304.7 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 and the COVID-19 pandemic and mitigation measures. For the six-months ended June 30, 2021, the Company used $12.2 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 June 30, 2021, the Company had cash and cash equivalents in the amount of $172.6 million, which consisted of depository 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 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 at June 30, 2021 will be sufficient to cover its expenses for at least the next twelve months from the date of issuance of these condensed 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 closely 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 during the six-month period ended June 30, 2021, 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 and Recent Accounting Pronouncements

6 Months Ended

Jun. 30, 2021

Summary of Significant Accounting Policies and Recent Accounting Pronouncements

2. Summary of Significant Accounting Policies and Recent Accounting Pronouncements:

Certain of the Company’s significant accounting policies are described below. All of the Company’s significant accounting policies are disclosed in the notes to the audited consolidated financial statements as of and for the year ended December 31, 2020 included in the Company’s Form 10-K. Since the date of such financial statements, the Company has adopted the new accounting pronouncements which are disclosed further in this note.

Consolidation

The accompanying condensed 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”); 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 condensed 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 condensed 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 condensed consolidated financial statements and there may be changes to those estimates in future periods. Actual results may differ from these estimates.

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 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.

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 condensed 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. 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.

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 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. Asset retirement obligations currently reported as other liabilities on the condensed consolidated balance sheet 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 condensed consolidated statements of operations and comprehensive loss.

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


	For the Six-Month Periods Ended June 30,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Amortization of interest		74		66
Effects of exchange rate		9		(39)
Balance at end of period	$	1,897	$	1,682

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 8 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 condensed 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 condensed consolidated statements 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 and other costs associated with clinical and preclinical activities and regulatory operations. 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 condensed consolidated financial statements as prepaid expenses or accrued expenses, as the case may be.

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 assumed to be 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 potential ordinary shares 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:


	June 30,	June 30,
	2021	2020
Share options	6,237,926	4,976,621
Restricted share units	1,175,000	545,000
Restricted ordinary shares subject to forfeiture	145,000	—
	7,557,926	5,521,621

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):


	June 30,		December 31,
	2021		2020
United States	$	23,923	$	17,536
United Kingdom		45,732		44,487
Ireland		45,303		27,413
Netherlands		4,760		1,685
Belgium		6		—
	$	119,724	$	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.

Equity Method and Other Investments

6 Months Ended

Jun. 30, 2021

Long-term Investments [Abstract]

Equity Method and Other Investments

3. Equity Method and Other Investments

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


		June 30, 2021
Investee	Investment Type	Ownership Percentage		Carrying Value		Cost Basis
Visiogene LLC	Equity Method Investment	25	%	$	5,165	$	5,165
Other	Equity Investment	3	%		1,500		1,500
Total equity method and other investments				$	6,665	$	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.

Accrued Expenses

6 Months Ended

Jun. 30, 2021

Payables and Accruals [Abstract]

Accrued Expenses

4. Accrued Expenses

Accrued expenses for the periods presented are comprised of the following (in thousands):


	June 30,		December 31,
	2021		2020
Clinical trial costs	$	9,869	$	10,261
Manufacturing costs		1,988		1,886
Fixed assets		1,537		949
Research and development		1,432		893
Compensation and benefits		1,270		3,791
Consulting		767		1,047
Professional fees		562		1,219
Other		134		815
	$	17,559	$	20,861

Share-Based Compensation

6 Months Ended

Jun. 30, 2021

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

Share-Based Compensation

5. 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 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.

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 year ended December 31, 2020 and the six-month period ended June 30, 2021 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, 2020		4,824,771	$	11.85	7.67	years
Granted		1,623,700	$	15.80
Exercised		(45,303)	$	7.94
Expired		(75,912)	$	8.18
Forfeited		(89,330)	$	15.46
Outstanding at June 30, 2021		6,237,926	$	13.00	7.85	years
Options exercisable at June 30, 2021		3,031,577	$	10.56	6.86	years
Aggregate intrinsic value of options outstanding as of June 30, 2021	$	22,702
Aggregate intrinsic value of options exercisable as of June 30, 2021	$	17,802

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 annual meeting of shareholders after the date of grant.

The total share-based compensation expense recorded in connection with the options was $3.9 million and $3.1 million, of which $1.5 million and $1.7 million was recorded as general and administrative expense and $2.4 million and $1.4 million was recorded as research and development expense during the three-month periods ended June 30, 2021 and 2020, respectively.

The total share-based compensation expense recorded in connection with the options was $7.6 million and $6.5 million, of which $3.2 million and $3.7 million was recorded as general and administrative expense and $4.4 million and $2.8 million was recorded as research and development expense during the six-month periods ended June 30, 2021 and 2020, respectively.

The total fair value of options vested during the three-month periods ended June 30, 2021 and 2020 was $4.3 million and $3.8 million, respectively.

The total fair value of options vested during the six-month periods ended June 30, 2021 and 2020 was $9.7 million and $5.5 million, respectively.

The weighted-average grant date fair value of options granted during the six-month periods ended June 30, 2021 and 2020 was $11.64 and $13.85 per share, 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:


	2021	2020
Risk-free interest rate	0.62 - 1.12%	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 June 30, 2021, the total compensation expense relating to unvested options granted that had not yet been recognized was $33.7 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

On January 8, 2020, March 6, 2020, and January 14, 2021 the Company granted 505,000, 40,000, and 505,000 RSUs, respectively, to certain members of senior management and a consultant. The RSUs were valued at $20.30, $16.45, and $16.43 per share, respectively. 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 in the condensed consolidated statements of operations and comprehensive loss.

These RSUs vest 50% on the second anniversary of the date of grant and 25% on each of the third and fourth anniversaries of the date of grant.

On June 10, 2021, the Company granted 125,000 RSUs to the non-employee members of the board of directors as part of their annual equity award grant. The RSUs were valued at $14.88 per share. The related share-based compensation expense, which is recognized ratably over the requisite service period, is included in general and administrative expenses in the condensed consolidated statements of operations and comprehensive loss.

The RSUs 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 will be paid on or within 30 days after the date a director ceases to serve on the board.

Total share-based compensation expense recorded in connection with the RSUs was $1.3 million and $0.7 million, of which $1.1 million and $0.6 million was recorded as general and administrative expense and $0.2 million and $0.1 million was recorded as research and development expense during the three-month periods ended June 30, 2021 and 2020, respectively.

Total share-based compensation expense recorded in connection with the RSUs was $2.4 million and $1.3 million, of which $2.0 million and $1.2 million was recorded as general and administrative expense and $0.4 million and $0.1 million was recorded as research and development expense during the six-month periods ended June 30, 2021 and 2020, respectively.

As of June 30, 2021, the total compensation expense relating to unvested RSUs granted that had not yet been recognized was $15.8 million, which is expected to be realized over a period of 3.5 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 six months after the effectiveness of the Company’s registration statement on Form S-1 filed with the Securities and Exchange Commission (“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 condensed 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.

Total compensation expense in connection with the issuance of those restricted ordinary shares, in the amount of $3.0 million, of which $1.3 million was share-based and $1.7 million was paid in cash, was recorded as general and administrative expense during the three-month period ended June 30, 2020.

Total compensation expense in connection with 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 six-month period ended June 30, 2020.

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

During the three-month and six-month periods ended June 30, 2021 and 2020 the Company recognized total share-based compensation expense in the accompanying condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three-month periods ended June 30,
	2021		2020
Research and development	$	2,559	$	1,464
General and administrative		2,644		3,592
Total share-based compensation	$	5,203	$	5,056


	Six-month periods ended June 30,
	2021		2020
Research and development	$	4,837	$	2,882
General and administrative		5,183		7,857
Total share-based compensation	$	10,020	$	10,739

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 six-month periods ended June 30, 2021 and 2020.

Ordinary Shares

6 Months Ended

Jun. 30, 2021

Equity [Abstract]

Ordinary Shares

6. Ordinary Shares

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.

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.

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Income Taxes

6 Months Ended

Jun. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

7. Income Taxes

The Company did not record a provision for income taxes for the three-month and six-month periods ended June 30, 2021 and 2020, as the Company has generated losses for all periods.

The Company periodically evaluates the realizability of its deferred tax assets based on all available evidence, both positive and negative. The realization of deferred tax assets is dependent on the Company’s ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. The Company weighed both positive and negative evidence and determined that there is a continued need for a full valuation allowance on its deferred tax assets (after consideration of the reversal of the deferred tax liabilities for the ROU assets and fixed assets) in the United States, United Kingdom, Ireland and Netherlands as of June 30, 2021. Should the Company determine that it would be able to realize its remaining deferred tax assets in the foreseeable

future, an adjustment to its remaining deferred tax assets would cause a material increase to income in the period such determination is made.

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.

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Related Party Transactions

Related Party Transactions

6 Months Ended

Jun. 30, 2021

8. 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 IRDs. 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 and 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 facility 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.

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 (“IND”) 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.

In 2019, the Company received a $100.0 million non-refundable upfront fee from Janssen and allocated this amount 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 three-month periods ended June 30, 2021 and 2020, the Company recognized $5.1 million and $2.5 million, respectively, of the deferred revenue – related party as license revenue.

During the six-month periods ended June 30, 2021 and 2020, the Company recognized $9.7 million and $6.7 million, respectively, of the deferred revenue – related party as license revenue.

The Company also recognized $18.1 million and $10.6 million during the three-month periods ended June 30, 2021 and 2020, respectively, related to the reimbursement of research and development expenses, which were recorded as an offset to research and development expenses.

The Company also recognized $30.2 million and $24.6 million during the six-month periods ended June 30, 2021 and 2020, respectively, related to the reimbursement of research and development expenses, which were recorded as an offset to research and development expenses.

As of June 30, 2021, the Company expects to recognize the remaining $64.2 million in deferred revenue associated with the non-refundable upfront fee over the estimated research and development period using the cost-to-cost input method over an estimated period of approximately 4.0 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
Deferred revenue recognized as license revenue during the six-month period ended June 30, 2021		(9,711)
Effects of exchange rate		1,079
Deferred revenue at June 30, 2021	$	64,210

Research Agreements

The Company is a party to several master services agreements with UCL Consultants Limited, an entity affiliated with University College of London (“UCL”), which is a shareholder of the Company. Pursuant to task orders to the master services agreements, UCL Consultants Limited provides clinical and pre-clinical research and development under the direction of the Company.

Total research and development expenses under these agreements for the three-month periods ended June 30, 2021 and 2020 were approximately $0.4 million and $0.5 million, respectively.

Total research and development expenses under these agreements for the six-month periods ended June 30, 2021 and 2020 were approximately $0.4 million and $0.5 million, respectively.

Future obligations under the agreements as of June 30, 2021 amounted to $0.4 million.

The amount due to UCL under the master services agreements at June 30, 2021 and December 31, 2020 is $0.1 million and $0.3 million, respectively, and is included in accounts payable and accrued expenses on the condensed consolidated balance sheets.

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 $55.1 million using the exchange rate at June 30, 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 £0.05 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 $2.0 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 $39.3 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 10^th anniversary of the first commercial sale of a product.

The Company incurred research and development expenses under the agreements in the amount of $0.04 million and $0 during the three-month periods ended June 30, 2021 and 2020, respectively.

The Company incurred research and development expenses under the agreements in the amount of $0.3 million and $0.2 million during the six-month periods ended June 30, 2021 and 2020, respectively.

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”). 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.

The Company did not incur any rent expense under this operating lease for the three-month periods ended June 30, 2021 and 2020.

The rent expense under this operating lease was $0 and $0.1 million for the six-month periods ended June 30, 2021 and 2020, respectively.

Kadmon Lease

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

During the three-month periods ended June 30, 2021 and 2020, the Company incurred and paid rent charges from Kadmon in the amount of $0.2 million and $0.1 million, respectively, which are included in loss from operations.

During the six-month periods ended June 30, 2021 and 2020, the Company incurred and paid rent charges from Kadmon in the amount of $0.3 and $0.3 million, respectively, which are included in loss from operations.

Leases

6 Months Ended

Jun. 30, 2021

Leases [Abstract]

Leases

9. Leases

The Company has commitments under operating leases for laboratory, warehouse and office space, as well as facilities to support clinical trial studies. 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 under these leases was $1.3 million and $0.9 million for the three-month periods ended June 30, 2021 and 2020, respectively.

Total rent expense under these leases was $2.4 million and $1.7 million for the six-month periods ended June 30, 2021 and 2020, respectively.

As of June 30, 2021, the Company has short term lease commitments amounting to approximately $0.05 million on a monthly basis for one lease for office space that is on a month-to-month lease.

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 condensed consolidated balance sheets as of June 30, 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 €0.03 million, or approximately $0.04 million, in the aggregate, which is subject to change depending on the annual maintenance costs within the Shannon Free Zone development.

During the six-month period ended June 30, 2021, the Company recognized seven operating leases for locations in connection with the Phase 3 Lumeos clinical trial of AAV-RPGR 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 condensed consolidated balance sheets as of June 30, 2021.

The components of lease cost for the three-month and six-month periods ended June 30, 2021 and 2020 are as follows (in thousands):


	Three-month periods ended June 30,
	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	313	$	72
Interest on lease liabilities		—		1
Total finance lease cost		313		73
Operating lease cost		1,285		901
Short-term lease cost		243		178
Total lease cost	$	1,841	$	1,152


	Six-month periods ended June 30,
	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	622	$	146
Interest on lease liabilities		1		2
Total finance lease cost		623		148
Operating lease cost		2,422		1,742
Short-term lease cost		433		340
Total lease cost	$	3,478	$	2,230

Amounts reported in the condensed consolidated balance sheets for leases where the Company is the lessee as of June 30, 2021 and December 31, 2020 were as follows (in thousands):


	June 30,			December 31,
	2021			2020
Operating leases
Right-of-use asset	$	24,666		$	21,486
Capitalized lease obligations	$	25,508		$	22,221
Finance leases
Right-of-use asset	$	29,490		$	21,596
Capitalized lease obligations	$	22		$	28
Weighted-average remaining lease term
Operating leases		7.0	years		7.0	years
Finance leases		177.2	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 for the three-month and six-month periods ended June 30, 2021 and 2020 are as follows (in thousands):


	Three-month periods ended June 30,
	2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	4	$	6
Operating cash flows from operating leases	$	1,258	$	805
Financing cash flows from finance leases	$	—	$	1

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	3,003	$	—
Finance leases	$	—	$	—


		Six-month periods ended June 30,
		2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	8	$	13
Operating cash flows from operating leases	$	2,444	$	1,542
Financing cash flows from finance leases	$	1	$	2

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	4,123	$	—
Finance leases	$	—	$	—

Future minimum lease payments under non-cancellable leases as of June 30, 2021 are as follows (in thousands):


	Operating Leases		Finance Leases
2021	$	2,554	$	9
2022		5,305		14
2023		5,435		—
2024		5,269		—
2025		5,271		—
Thereafter		9,444		—
Total undiscounted lease payments	$	33,278	$	23
Less: Imputed interest		(7,770)		(1)
Total lease liabilities	$	25,508	$	22

Commitments

6 Months Ended

Jun. 30, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments

10. Commitments

There were no new material commitments entered into during the six-month period ended June 30, 2021.

Subsequent Events

6 Months Ended

Jun. 30, 2021

Subsequent Events [Abstract]

Subsequent Events

11. Subsequent Events

Management has evaluated subsequent events through the date of this filing. Based on its evaluation, there were no subsequent events to report.

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)

6 Months Ended

Jun. 30, 2021

Equity Method and Other Investments

Consolidation

The accompanying condensed 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”); 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

Fair Value Measurements

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.

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 Six-Month Periods Ended June 30,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Amortization of interest		74		66
Effects of exchange rate		9		(39)
Balance at end of period	$	1,897	$	1,682

Collaboration Arrangements

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

incurred, and are reflected in the condensed consolidated financial statements as prepaid expenses or accrued expenses, as the case may be.

Net Loss per Ordinary Share


	June 30,	June 30,
	2021	2020
Share options	6,237,926	4,976,621
Restricted share units	1,175,000	545,000
Restricted ordinary shares subject to forfeiture	145,000	—
	7,557,926	5,521,621

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):


	June 30,		December 31,
	2021		2020
United States	$	23,923	$	17,536
United Kingdom		45,732		44,487
Ireland		45,303		27,413
Netherlands		4,760		1,685
Belgium		6		—
	$	119,724	$	91,121

Recent Accounting Pronouncements Not Yet Adopted

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Tables)

6 Months Ended

Jun. 30, 2021

Schedule of Change in Asset Retirement Obligations

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


	For the Six-Month Periods Ended June 30,
	2021		2020
Balance at beginning of period	$	1,814	$	1,655
Amortization of interest		74		66
Effects of exchange rate		9		(39)
Balance at end of period	$	1,897	$	1,682

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


	June 30,	June 30,
	2021	2020
Share options	6,237,926	4,976,621
Restricted share units	1,175,000	545,000
Restricted ordinary shares subject to forfeiture	145,000	—
	7,557,926	5,521,621

Summary of Non-Current Assets by Geographical Area

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


	June 30,		December 31,
	2021		2020
United States	$	23,923	$	17,536
United Kingdom		45,732		44,487
Ireland		45,303		27,413
Netherlands		4,760		1,685
Belgium		6		—
	$	119,724	$	91,121

Equity Method and Other Investments (Tables)

6 Months Ended

Jun. 30, 2021

Long-term Investments [Abstract]

Schedule of investments

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


		June 30, 2021
Investee	Investment Type	Ownership Percentage		Carrying Value		Cost Basis
Visiogene LLC	Equity Method Investment	25	%	$	5,165	$	5,165
Other	Equity Investment	3	%		1,500		1,500
Total equity method and other investments				$	6,665	$	6,665

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2021

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses for the periods presented are comprised of the following (in thousands):


	June 30,		December 31,
	2021		2020
Clinical trial costs	$	9,869	$	10,261
Manufacturing costs		1,988		1,886
Fixed assets		1,537		949
Research and development		1,432		893
Compensation and benefits		1,270		3,791
Consulting		767		1,047
Professional fees		562		1,219
Other		134		815
	$	17,559	$	20,861

Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 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, 2020		4,824,771	$	11.85	7.67	years
Granted		1,623,700	$	15.80
Exercised		(45,303)	$	7.94
Expired		(75,912)	$	8.18
Forfeited		(89,330)	$	15.46
Outstanding at June 30, 2021		6,237,926	$	13.00	7.85	years
Options exercisable at June 30, 2021		3,031,577	$	10.56	6.86	years
Aggregate intrinsic value of options outstanding as of June 30, 2021	$	22,702
Aggregate intrinsic value of options exercisable as of June 30, 2021	$	17,802

Schedule of Grant Date Fair Values of the Stock Options Granted


	2021	2020
Risk-free interest rate	0.62 - 1.12%	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

Schedule of Share-Based Compensation Expense


	Three-month periods ended June 30,
	2021		2020
Research and development	$	2,559	$	1,464
General and administrative		2,644		3,592
Total share-based compensation	$	5,203	$	5,056


	Six-month periods ended June 30,
	2021		2020
Research and development	$	4,837	$	2,882
General and administrative		5,183		7,857
Total share-based compensation	$	10,020	$	10,739

Related Party Transactions (Tables)

6 Months Ended

Jun. 30, 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
Deferred revenue recognized as license revenue during the six-month period ended June 30, 2021		(9,711)
Effects of exchange rate		1,079
Deferred revenue at June 30, 2021	$	64,210

Leases (Tables)

6 Months Ended

Jun. 30, 2021

Leases [Abstract]

Schedule of Components of Lease Cost

The components of lease cost for the three-month and six-month periods ended June 30, 2021 and 2020 are as follows (in thousands):


	Three-month periods ended June 30,
	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	313	$	72
Interest on lease liabilities		—		1
Total finance lease cost		313		73
Operating lease cost		1,285		901
Short-term lease cost		243		178
Total lease cost	$	1,841	$	1,152


	Six-month periods ended June 30,
	2021		2020
Finance lease cost
Amortization of right-of-use assets	$	622	$	146
Interest on lease liabilities		1		2
Total finance lease cost		623		148
Operating lease cost		2,422		1,742
Short-term lease cost		433		340
Total lease cost	$	3,478	$	2,230

Schedule of Consolidated Balance Sheets for Leases

Amounts reported in the condensed consolidated balance sheets for leases where the Company is the lessee as of June 30, 2021 and December 31, 2020 were as follows (in thousands):


	June 30,			December 31,
	2021			2020
Operating leases
Right-of-use asset	$	24,666		$	21,486
Capitalized lease obligations	$	25,508		$	22,221
Finance leases
Right-of-use asset	$	29,490		$	21,596
Capitalized lease obligations	$	22		$	28
Weighted-average remaining lease term
Operating leases		7.0	years		7.0	years
Finance leases		177.2	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 for the three-month and six-month periods ended June 30, 2021 and 2020 are as follows (in thousands):


	Three-month periods ended June 30,
	2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	4	$	6
Operating cash flows from operating leases	$	1,258	$	805
Financing cash flows from finance leases	$	—	$	1

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	3,003	$	—
Finance leases	$	—	$	—


		Six-month periods ended June 30,
		2021		2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	8	$	13
Operating cash flows from operating leases	$	2,444	$	1,542
Financing cash flows from finance leases	$	1	$	2

Right-of-use assets obtained in exchange for lease liabilities
Operating leases	$	4,123	$	—
Finance leases	$	—	$	—

Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases

Future minimum lease payments under non-cancellable leases as of June 30, 2021 are as follows (in thousands):


	Operating Leases		Finance Leases
2021	$	2,554	$	9
2022		5,305		14
2023		5,435		—
2024		5,269		—
2025		5,271		—
Thereafter		9,444		—
Total undiscounted lease payments	$	33,278	$	23
Less: Imputed interest		(7,770)		(1)
Total lease liabilities	$	25,508	$	22

Organization and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Description Of Business [Line Items]
Accumulated deficit	$ (304,732)		$ (261,028)
Cash flows from operations	(12,175)	$ (25,264)
Cash, cash equivalents and restricted cash	$ 172,556	$ 194,811	$ 209,520	$ 227,357
Minimum
Schedule Of Description Of Business [Line Items]
Offsetting expense, period	12 months

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Summary of Significant Accounting Policies - Schedule of Change in Asset Retirement Obligations (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Asset Retirement Obligation [Abstract]
Balance at beginning of period	$ 1,814	$ 1,655
Amortization of interest	74	66
Effects of exchange rate	9	(39)
Balance at end of period	$ 1,897	$ 1,682

Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings per Share (Details) - shares	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	7,557,926	5,521,621
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	1,175,000	545,000
Share Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	6,237,926	4,976,621
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earning per share, amount	145,000

Summary of Significant Accounting Policies - Summary of Non-Current Assets by Geographical Area (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Operation By Geographical [Line Items]
Non-current assets	$ 119,724	$ 91,121
United States
Operation By Geographical [Line Items]
Non-current assets	23,923	17,536
United Kingdom
Operation By Geographical [Line Items]
Non-current assets	45,732	44,487
Ireland
Operation By Geographical [Line Items]
Non-current assets	45,303	27,413
Netherlands
Operation By Geographical [Line Items]
Non-current assets	4,760	$ 1,685
Belgium
Operation By Geographical [Line Items]
Non-current assets	$ 6

Equity Method and Other Investments - Summary of Investments (Details) $ in Thousands	Jun. 30, 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
Visiogene LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Carrying Value	$ 5,165
Cost Basis	$ 5,165

Equity Method and Other Investments (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 04, 2021	Mar. 31, 2021
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
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

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Clinical trial costs	$ 9,869	$ 10,261
Manufacturing costs	1,988	1,886
Fixed assets	1,537	949
Research and development	1,432	893
Compensation and benefits	1,270	3,791
Consulting	767	1,047
Professional fees	562	1,219
Other	134	815
Accrued Expenses	$ 17,559	$ 20,861

Share-Based Compensation - Additional Information (Details)						3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 10, 2021 $ / shares shares	Jan. 14, 2021 $ / shares shares	Mar. 06, 2020 $ / shares shares	Jan. 08, 2020 $ / shares shares	Jun. 07, 2018 item $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) $ / shares	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual life of options, outstanding								7 years 10 months 6 days		7 years 8 months 1 day
Fair value of options Vested						$ 4,300,000	$ 3,800,000	$ 9,700,000	$ 5,500,000
Weighted average grant date fair value of options granted \| $ / shares								$ 11.64	$ 13.85
Share options granted during the period \| shares								1,623,700
Share-based compensation								$ 10,020,000	$ 10,739,000
Total share-based compensation						5,203,000	5,056,000	10,020,000	10,739,000
Excess tax benefits, operating activities								0	0
Excess tax benefits, financing activities								$ 0	0
Maximum [Member]
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						2,644,000	3,592,000	$ 5,183,000	7,857,000
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation						2,559,000	1,464,000	$ 4,837,000	2,882,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period expected to realize unrecognized compensation expense								3 years 6 months
Total compensation expense not yet recognized relating to unvested RSUs						15,800,000		$ 15,800,000
Total share-based compensation						1,300,000	700,000	2,400,000	1,300,000
Restricted Stock Units (RSUs) \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation						1,100,000	600,000	2,000,000.0	1,200,000
Restricted Stock Units (RSUs) \| Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation						200,000	100,000	400,000	100,000
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unvested options compensation expense not yet recognized						33,700,000		$ 33,700,000
Period expected to realize unrecognized compensation expense								4 years
Total share-based compensation						3,900,000	3,100,000	$ 7,600,000	6,500,000
Share Options \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation						1,500,000	1,700,000	3,200,000	3,700,000
Share Options \| Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation						$ 2,400,000	1,400,000	$ 4,400,000	2,800,000
Senior Management [Member] \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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							3,000,000.0		6,500,000
Total share-based compensation							1,300,000		2,900,000
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							$ 1,700,000		$ 3,600,000
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								36 months
Director [Member] \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options granted during the period \| shares	125,000
Ordinary shares awarded, per share \| $ / shares	$ 14.88
Certain members of senior management and a consultant \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options granted during the period \| shares		505,000	40,000	505,000
Ordinary shares awarded, per share \| $ / shares		$ 16.43	$ 16.45	$ 20.30
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] \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								25.00%
Fourth Anniversary [Member] \| Restricted Stock Units (RSUs)
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)	6 Months Ended	12 Months Ended
	Jun. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2020 $ / shares shares
Number of Options
Number of options, Beginning balance \| shares	4,824,771
Number of options, Granted \| shares	1,623,700
Number of options, Exercised \| shares	(45,303)
Number of options, Expired \| shares	(75,912)
Number of options, Forfeited \| shares	(89,330)
Number of options, Ending balance \| shares	6,237,926	4,824,771
Weighted-Average Exercise Price
Weighted-average exercise price, Beginning balance \| $ / shares	$ 11.85
Weighted-average exercise price, Granted \| $ / shares	15.80
Weighted-average exercise price, Exercised \| $ / shares	7.94
Weighted-average exercise price, Expired \| $ / shares	8.18
Weighted-average exercise price, Forfeited \| $ / shares	15.46
Weighted-average exercise price, Ending balance \| $ / shares	$ 13.00	$ 11.85
Options additional disclosures
Number of options, Options exercisable \| shares	3,031,577
Weighted-average exercise price, Option exercisable \| $ / shares	$ 10.56
Weighted-average remaining contractual life of options, outstanding	7 years 10 months 6 days	7 years 8 months 1 day
Weighted-average remaining contractual life of options, exercisable	6 years 10 months 9 days
Aggregate intrinsic value, options outstanding \| $	$ 22,702
Aggregate intrinsic value, options exercisable \| $	$ 17,802

Share-Based Compensation - Schedule of Grant Date Fair Values of the Share Options Granted Black-Scholes Valuation Model (Details) - Share Options	6 Months Ended
	Jun. 30, 2021	Jun. 30, 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	1.12%	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 [Member]
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 - Schedule of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Expense [Line Items]
Total share-based compensation	$ 5,203	$ 5,056	$ 10,020	$ 10,739
General and Administrative Expense [Member]
Share Based Compensation Expense [Line Items]
Total share-based compensation	2,644	3,592	5,183	7,857
Research and Development Expenses [Member]
Share Based Compensation Expense [Line Items]
Total share-based compensation	$ 2,559	$ 1,464	$ 4,837	$ 2,882

Ordinary Shares - Additional Information (Details) - Visiogene License Agreement - USD ($) $ in Thousands		3 Months Ended
	Jan. 04, 2021	Mar. 31, 2021
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]
Ordinary shares issued in connection with a license agreement (in shares)		75,000

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 0	$ 0	$ 0	$ 0

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

+ References + Details

Related Party Transactions - Collaboration and License Agreements (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 30, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Feb. 27, 2019
Related Party Transaction [Line Items]
Shares issued to related party		44,309,453		44,309,453		44,189,150
Collaboration Agreement \| Janssen Pharmaceuticals Inc
Related Party Transaction [Line Items]
Reimbursement of research and development expenses		$ 18,100	$ 10,600
Estimated period to recognize remaining deferred revenue				4 years
Deferred revenue - related party		9,700	6,700	$ 9,700	$ 6,700
Clinical IRD Product Candidate development \| Maximum [Member]
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
Deferred revenue - related party recognized as license revenue		5,100	$ 2,500	9,711		$ 15,563
Reimbursement of research and development expenses				30,200	$ 24,600
Revenue, remaining performance obligation, amount		64,200		64,200
Deferred revenue - related party		$ 64,210		$ 64,210		$ 72,842	$ 86,214
Janssen Pharmaceuticals Inc \| Research, development and commercialization of gene therapies \| Collaboration 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 clinical and commercialization costs to be paid by related party	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 - Revenue Recognition (Details) - Janssen Pharmaceuticals Inc - Collaboration Agreement - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Deferred revenue	$ 64,210		$ 64,210	$ 72,842	$ 86,214
Deferred revenue recognized as license revenue during period	$ (5,100)	$ (2,500)	(9,711)	(15,563)
Effects of exchange rate			$ 1,079	$ 2,191

Related Party Transactions - Research Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Research and development expenses	$ 15,190	$ 16,202	$ 31,900	$ 24,285
UCL Consultants Limited \| Master Services Agreement [Member]
Related Party Transaction [Line Items]
Research and development expenses	400	$ 500	400	$ 500
Future obligations under agreement	400		400
UCL Consultants Limited \| Master Services Agreement [Member] \| Accounts Payable And Accrued Expenses
Related Party Transaction [Line Items]
Amount due under services agreement	$ 100		$ 100		$ 300

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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