Subsequent Events	12 Months Ended
Dec. 31, 2020
Subsequent Events
Subsequent Events	16. Subsequent Events In February 2021, Neurocrine notified the Company that it had elected to terminate the Neurocrine Collaboration solely with regards to the VY-AADC Program, effective August 2, 2021 (the “Neurocrine VY-AADC Program Termination Effective Date”). The Neurocrine Collaboration Agreement remains in full force and effect for each other program thereunder. As a result of the termination, as of the Neurocrine VY-AADC Program Termination Effective Date, the license granted by the Company to Neurocrine thereunder regarding the VY-AADC Program shall expire and the Company shall regain worldwide intellectual property rights regarding the VY-AADC Program, in each case in accordance with the terms of the Neurocrine Collaboration Agreement. The Company intends to support Neurocrine, the study sponsor and IND holder, on ongoing matters related to the completion of imaging and clinical assessments requested by the DSMB and the provision of other information requested by the FDA for the RESTORE-1 Phase 2 clinical trial.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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