Subsequent Event	9 Months Ended
Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent Event	15. Subsequent event In October 2023, the Company announced a portfolio update to increase its focus on its ex vivo cell therapy product candidates. In addition to an increased focus on its ex vivo programs, the Company announced reduced near-term investment in its fusogen platform for in vivo gene delivery, including the delay of the investigational new drug application submission for its SG299 program. The strategic repositioning resulted in a workforce reduction of approximately 29%. The Company expects to incur approximately $6.8 million of cash-based expenses related to employee severance, benefits, and related costs. The Company anticipates that the portfolio update and associated workforce reduction will be substantially complete by the first quarter of 2024.

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
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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