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Grant Award Clinical Development Number Of Patients Treatment Completed

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Proceeds From Grant Awards

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Balance Sheet Components - Additional Information (Details)			3 Months Ended		12 Months Ended
	May 12, 2025	Apr. 26, 2024 USD ($) patient	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Apr. 28, 2025 USD ($)
Restructuring Cost and Reserve [Line Items]
Proceeds from CIRM award (Note 5)			$ 0	$ 3,350,000
Interest expense			300,000	150,000
California Institute For Regenerative Medicine (CIRM)
Restructuring Cost and Reserve [Line Items]
Grant award, amount		$ 15,000,000.0				$ 9,200,000
Number of patients treated \| patient		20
Grant award, grantee maximum expected contribution		$ 15,700,000
Grant award, royalty fee, amount due to other party, multiplier		9
Grant award, loan conversion period deadline, anniversary of award		10 years
Basis spread on variable rate		10.00%
Proceeds from CIRM award (Note 5)			9,200,000
Interest expense			300,000	200,000
Accrued interest			1,600,000
California Institute For Regenerative Medicine (CIRM) \| Minimum
Restructuring Cost and Reserve [Line Items]
Converted to loan, repayment percentage		0.80
California Institute For Regenerative Medicine (CIRM) \| Maximum
Restructuring Cost and Reserve [Line Items]
Converted to loan, repayment percentage		1
Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Positions eliminated, percent	28.00%
Restructuring costs			0	$ 0
Restructuring reserve			$ 0
Workforce Reduction \| Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring costs					$ 3,100,000
Workforce Reduction \| General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs					300,000
Workforce Reduction \| Equipment impairment
Restructuring Cost and Reserve [Line Items]
Restructuring costs					$ 1,300,000