Product revenue and reserves - Summary of Product Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Revenue from External Customer [Line Items]
Revenue	$ 29,065	$ 2,739
ZYNTEGLO
Revenue from External Customer [Line Items]
Revenue	16,692	2,739
SKYSONA
Revenue from External Customer [Line Items]
Revenue	$ 12,373	$ 0

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details