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

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Funding received from the Company's collaboration agreement with Janssen Pharmaceuticals for the research, development and commercialization of gene therapies for the treatment of inherited retinal diseases..

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Maximum contingent funding available under 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 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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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Organization and Basis of Presentation (Details) - USD ($) $ in Thousands	1 Months Ended			6 Months Ended
	Dec. 31, 2023	Dec. 31, 2021	Mar. 31, 2019	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accumulated deficit	$ 554,231			$ 623,293
Cash flows from operations				56,197	$ 66,404
Cash, cash equivalents	130,649			101,025	$ 92,773	$ 115,516
Janssen Pharmaceuticals Inc \| Collaborative Arrangement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Initial funding			$ 100,000
Milestone funding		$ 30,000
Janssen Pharmaceuticals Inc \| Asset Purchase Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Non-refundable upfront cash funding	65,000
Milestone funding for extension of RPGR product clinical trials				$ 50,000
Milestone funding for development of drug substances	10,000
Milestone funding for development of drug products	5,000
Milestone funding for sale of drug products in the US	175,000
Milestone funding for sale of drug products in the UK, France, Germany, Spain and Italy	75,000
Milestone funding for transfer of manufacturing technology	25,000
Milestone funding upon regulatory approval	10,000
Maximum [Member] \| Janssen Pharmaceuticals Inc \| Asset Purchase Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent Funding Available	$ 350,000