| Cover | Jan. 28, 2021 |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | Amendment No. 1 |
| Document Period End Date | Jan. 28, 2021 |
| Entity File Number | 001-39935 |
| Entity Registrant Name | BIOTECH ACQUISITION COMPANY |
| Entity Central Index Key | 0001825413 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Address, Address Line One | 545 West 25th |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-half of one redeemable warrant | |
| Title of 12(b) Security | Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-half of one redeemable warrant |
| Trading Symbol | BIOTU |
| Security Exchange Name | NASDAQ |
| Class A ordinary shares | |
| Title of 12(b) Security | Class A ordinary shares |
| Trading Symbol | BIOT |
| Security Exchange Name | NASDAQ |
| Redeemable warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 | |
| Title of 12(b) Security | Redeemable warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 |
| Trading Symbol | BIOTW |
| Security Exchange Name | NASDAQ |
