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Related party transactions - Additional information (Detail) - USD ($)					3 Months Ended	12 Months Ended
	Mar. 25, 2025	Sep. 26, 2024	Apr. 22, 2024	Aug. 11, 2023	Dec. 31, 2024	Jun. 30, 2025	Mar. 31, 2025	Sep. 12, 2024	Aug. 29, 2024	Jun. 30, 2024	May 16, 2024	Apr. 28, 2024	Apr. 26, 2024	Oct. 17, 2023	Sep. 15, 2022	Apr. 22, 2020
Related Party Transaction [Line Items]
Existing warrants waive percentage of beneficial ownership limitation.									19.99%
Common Stock, Value Issued						$ 2,000				$ 1,000
Common Stock, Shares Issued					23,451,475	26,250,469	25,546,288			10,086,119
Proceeds From Issuance Of Warrants					$ 2,000	$ 67,000
Class of warrant or right, exercise price of warrants or rights			$ 0.0001												$ 11.22
Common stock, par or stated value per share					$ 0.0001	$ 0.0001				$ 0.0001
Gross proceeds from issuance of warrants			$ 40,000,000
Class of warrant purchase price per warrant			$ 4.7999
Warrants convertible into shares of common stock on exercise			2,584,239
Sale of stock issue price per share			$ 4.8	$ 1.9299
Sale of stock number of shares issued in the transaction			5,749,152
Common Stock [Member]
Related Party Transaction [Line Items]
Class of warrant or right, exercise price of warrants or rights						$ 0.0001
Warrants convertible into shares of common stock on exercise				2,331,606	458,134											6,300
Sale of stock number of shares issued in the transaction				875,949
Common Stock [Member] | Securities Purchase Agreement [Member]
Related Party Transaction [Line Items]
Proceeds From Issuance Of Warrants	$ 28,200,000
Gross proceeds from exercise of warrants	$ 30,500,000
Issue of common stock and warrant price per share	13.00%
Sale of stock issue price per share	$ 13
Sale of stock number of shares issued in the transaction	900,000
Common Stock [Member] | Underwriting agreement [member]
Related Party Transaction [Line Items]
Issue of common stock and warrant price per share	13.00%
Common stock, par or stated value per share	$ 0.0001
Sale of stock number of shares issued in the transaction	1,143,000
2023 Common Warrants [Member]
Related Party Transaction [Line Items]
Proceeds From Issuance Of Warrants				$ 28,600,000
Class of warrant or right, exercise price of warrants or rights				$ 3.86
Sale of stock number of shares issued in the transaction				16,002,175
Pre-funded warrants [Member]
Related Party Transaction [Line Items]
Proceeds From Issuance Of Warrants			$ 37,100,000
Class of warrant or right, exercise price of warrants or rights		$ 0.0001	$ 0.0001	$ 0.0001				$ 0.0001			$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Gross proceeds from issuance of warrants			$ 40,000,000
Class of warrant purchase price per warrant			$ 4.7999
Sale of stock issue price per share				$ 1.9298
Sale of stock number of shares issued in the transaction				15,126,226
Pre-funded warrants [Member] | Underwriting agreement [member]
Related Party Transaction [Line Items]
Class of warrant or right, exercise price of warrants or rights	$ 0.0001
Debt conversion, converted instrument, warrants or options issued	300,000
Issue of common stock and warrant price per share	12.999%
Chief Financial Officer [Member] | 2023 Offerings [Member]
Related Party Transaction [Line Items]
Common Stock, Value Issued				$ 50,000
Common Stock, Shares Issued				25,907
Director [Member] | 2023 Offerings [Member]
Related Party Transaction [Line Items]
Common Stock, Value Issued				$ 99,999
Common Stock, Shares Issued				51,813
Franklin Resources, Inc. [Member]
Related Party Transaction [Line Items]
Sale of stock net consideration received on the transaction			$ 1,000,003
Suvretta Capital [Member]
Related Party Transaction [Line Items]
Waive percentage of beneficial ownership limitation.									49.90%
Description of agreement with affilated entity for waive		Suvretta Capital waived the 19.99% beneficial ownership limitation set forth in each of the warrants held by the Suvretta Funds, and (ii) Suvretta Capital and the Company agreed that Suvretta Capital will not be permitted to complete an exercise of the warrants held by the Suvretta Funds to the extent the beneficial ownership (calculated as provided in the applicable warrants) of Suvretta Capital in the Company following such exercise would exceed 49.9%
Sale of stock net consideration received on the transaction			$ 16,750,004

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