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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Face (par) amount of debt instrument at time of issuance.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Related Party Transactions - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		5 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Feb. 21, 2023	Jul. 25, 2022
Related Party Transaction [Line Items]
Accounts payable, due to related party	$ 649		$ 649	$ 649		$ 135
Notes payable	1,960		$ 1,960	1,960		$ 2,007
Gain of change in fair value of the instrument	$ 2,672			$ 7,631	$ (156)
Number of shares called by warrants issued	283,862,907		283,862,907	283,862,907		24,733,365
RIF Transaction
Related Party Transaction [Line Items]
Principal amount	$ 16,300		$ 16,300	$ 16,300
PureTech
Related Party Transaction [Line Items]
Loss of change in fair value of convertible promissory notes	200			300
Interest and issuance cost amortization	200			600
PureTech \| 2022 Promissory Notes
Related Party Transaction [Line Items]
Principal amount								$ 15,000
Notes payable	12,100		12,100	12,100		$ 16,600
Gain of change in fair value of the instrument	1,600			4,500
PureTech \| Management Services Expenses
Related Party Transaction [Line Items]
Research and development, including related party expenses	100	$ 100		300	300
Accounts payable, due to related party	600		600	600		100
PureTech \| Royalty Expense
Related Party Transaction [Line Items]
Research and development, including related party expenses		$ 100		100	$ 300
SSD2 \| 2022 Promissory Notes
Related Party Transaction [Line Items]
Principal amount	4,000		4,000	4,000		5,500		$ 5,000
Gain of change in fair value of the instrument				$ 500		$ 1,500
Maximum \| PureTech \| Royalty Expense
Related Party Transaction [Line Items]
Research and development, including related party expenses	$ 100
Note and Warrant Purchase Agreement \| PureTech
Related Party Transaction [Line Items]
Gross proceeds			$ 10,400
Note and Warrant Purchase Agreement \| PureTech \| Warrants
Related Party Transaction [Line Items]
Number of shares called by warrants issued	259,129,542		259,129,542	259,129,542
Note and Warrant Purchase Agreement \| PureTech \| NPA Convertible Senior Secured Notes
Related Party Transaction [Line Items]
Principal amount	$ 8,200		$ 8,200	$ 8,200
Note and Warrant Purchase Agreement \| PureTech \| Senior Secured Note
Related Party Transaction [Line Items]
Aggregate principal amount of notes	$ 10,400		$ 10,400	$ 10,400
Note and Warrant Purchase Agreement \| Maximum \| PureTech \| Warrants
Related Party Transaction [Line Items]
Exercise price of warrants							$ 0.2744
Note and Warrant Purchase Agreement \| Minimum \| PureTech \| Warrants
Related Party Transaction [Line Items]
Exercise price of warrants							$ 0.0142