Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 07, 2022	Jun. 30, 2021
Document Information Line Items
Entity Registrant Name	BIOTECH ACQUISITION COMPANY
Trading Symbol	BIOT
Document Type	10-K
Current Fiscal Year End Date	--12-31
Entity Public Float			$ 222,410,000
Amendment Flag	false
Entity Central Index Key	0001825413
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-39935
Entity Incorporation, State or Country Code	E9
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	545 West 25th Street
Entity Address, Address Line Two	20th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10001
City Area Code	(212)
Local Phone Number	227-1905
Title of 12(b) Security	Class A ordinary shares
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Auditor Firm ID	688
Auditor Name	Marcum LLP
Auditor Location	Philadelphia, PA
Class A Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		23,000,000
Class B Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		5,750,000