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Days of written notice needed in order to terminate the asset purchase agreement.

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Funding received from the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Maximum contingent funding available under the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Initial duration period of the asset purchase agreement.

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Milestone funding received and allocated to performance obligation for commercial supply of RPGR product.

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Milestone funding received and allocated to performance obligation for manufacturing technology transfer.

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Milestone funding received and allocated to performance obligation for process performance qualification (PPQ) services.

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Milestone funding received and allocated to performance obligation for sale of nonfinancial assets.

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Milestone funding received for the completion of certain specified development services for the drug product for the RPGR Product in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the completion of certain specified development services for the drug substance for the RPGR Product in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the achievement of the initiation of the extension study for the Phase 3 LUMEOS clinical trial for the RPGR Product in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the regulatory approval of a Janssen-selected manufacturing facility in each of the United States and European Union for commercial manufacture of the RPGR Product in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the first commercial sale of an RPGR Product in at least one of the United Kingdom, France, Germany, Spain and Italy in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the first commercial sale of an RPGR Product in the United States in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received for the transfer of certain manufacturing technology for drug substance and drug product from the Company to Janssen in connection with the Company's asset purchase agreement with Janssen Pharmaceuticals.

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Milestone funding received from the Company's collaboration agreement with Janssen Pharmaceuticals.

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Offsetting credit for transition services in determining contract price under license agreement.

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Percentage of the clinical and commercialization costs of the products candidates to be paid by related party.

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License agreement contract price allocated to performance obligation for commercial supply of RPGR product.

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License agreement contract price allocated to performance obligation for manufacturing technology transfer.

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License agreement contract price allocated to performance obligation for process performance qualification (PPQ) services.

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License agreement contract price allocated to performance obligation for sale of nonfinancial assets.

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Amount of income recognized from deferred related-party revenues.

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Related-party deferred revenue reclassified under provisions of new license agreement.

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Amount of related party income recognized for transition services.

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Amount of royalties receivable on net sales of products and additional development and commercialization milestones.

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Amount of royalties receivable on net sales of products and additional development and commercialization milestones, as a percent.

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Variable consideration included in provisions of new license agreement.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Related Party Transactions - Collaboration and License Agreements (Details) - USD ($)				1 Months Ended		3 Months Ended		6 Months Ended
	Dec. 20, 2023	Nov. 09, 2022	Jan. 30, 2019	Dec. 31, 2023	Dec. 31, 2021	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Feb. 27, 2019
Related Party Transaction [Line Items]
Common stock, shares issued				63,601,015		64,684,187		64,684,187
Offering costs								$ 644,000	$ 4,003,000
Shares issued to related party				63,601,015		64,684,187		64,684,187
Gain on sale of nonfinancial assets								$ 29,018,000
JJDC \| Private Placement
Related Party Transaction [Line Items]
Common stock, shares issued		3,742,514								2,898,550
Aggregate Offer Price		$ 6.68
Proceeds from Issuance of Private Placement		$ 25,000,000.0
Shares issued to related party		3,742,514								2,898,550
Janssen Pharmaceuticals Inc \| Collaboration Agreement \| Research and Development Expenses
Related Party Transaction [Line Items]
Recognized revenue for transition services - related party						$ 1,300,000	$ 21,800,000	1,600,000	44,400,000
Janssen Pharmaceuticals Inc \| Collaboration Agreement \| License revenue - related party
Related Party Transaction [Line Items]
Deferred revenue - related party recognized						$ 300,000	$ 3,500,000	1,000,000.0	$ 6,900,000
Janssen Pharmaceuticals Inc \| Asset Purchase Agreement
Related Party Transaction [Line Items]
Milestone payment allocated to performance obligations								20,982,000
Deferred revenue recognized as service revenue during the three-month period								(979,000)
Initial agreement term	4 years
Written days-notice to terminate agreement	90 days
Non-refundable upfront cash funding				$ 65,000,000.0
Milestone funding for extension of RPGR product clinical trials								50,000,000.0
Milestone funding for development of drug substances				10,000,000.0
Milestone funding for development of drug products				5,000,000.0
Milestone funding for sale of drug products in the US				175,000,000.0
Milestone funding for sale of drug products in the UK, France, Germany, Spain and Italy				75,000,000.0
Milestone funding for transfer of manufacturing technology				25,000,000.0
Milestone funding upon regulatory approval				10,000,000.0
Deferred revenue - related party included in contract price of license agreement				30,600,000
Variable consideration for services included in contract price of license agreement				1,800,000
Contract price of license agreement				92,300,000
Offsetting credit for transition services				5,100,000
Performance obligation for process performance qualification services				2,900,000
Performance obligation for commercial supply of RPGR product				6,900,000
Performance obligation for manufacturing technology transfer				28,700,000
Performance obligation for sale of nonfinancial assets				53,800,000
Milestone funding allocated to process performance qualification services								1,600,000
Milestone funding allocated to commercial supply of RPGR product								3,800,000
Milestone funding allocated to manufacturing technology transfer								15,600,000
Milestone funding allocated to sale of nonfinancial assets								$ 29,000,000.0
Janssen Pharmaceuticals Inc \| Asset Purchase Agreement \| Maximum
Related Party Transaction [Line Items]
Contingent Funding Available				$ 350,000,000.0
Janssen Pharmaceuticals Inc \| Research, development and commercialization of gene therapies \| Collaboration Agreement
Related Party Transaction [Line Items]
Milestone funding					$ 30,000,000.0
Non-refundable upfront cash funding			$ 100,000,000.0
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%
Royalties receivable, as a percentage			20.00%
Milestone funding					$ 30,000,000.0
Janssen Pharmaceuticals Inc \| Clinical IRD Product Candidate development \| Collaboration Agreement \| Maximum
Related Party Transaction [Line Items]
Additional development and commercialization milestones			$ 340,000,000.0