FDA 483 - 2seventy Bio, Inc. - March 20, 2025

During an FDA inspection conducted from March 17-20, 2025, at 2seventy bio, Inc. in Cambridge, MA, the agency issued a Form FDA 483 citing an observation related to laboratory control records. The primary issue identified was that the firm's laboratory records did not contain complete documentation for the testing and standardization of a critical laboratory reference standard. Specifically, the DNA plasmid reference standard used in test method TM-0059, which determines Lentiviral Vector Titer for the viral vector Anti-BCMA02 CAR aLVV utilized in manufacturing the drug product ABECMA, was not adequately qualified. The inspection revealed conflicting data across three different testing reports regarding the expected size of this DNA plasmid. This inadequately qualified reference standard has been in continuous use for testing viral vector batches since before 2021. This observation indicates a deficiency in adhering to good manufacturing practices concerning laboratory controls. As per the regulatory framework of Section 704(b) of the Federal Food, Drug, and Cosmetic Act, 2seventy bio, Inc. is expected to address this observation by implementing appropriate corrective actions and submitting their response to the FDA.