Company: ATRA
Filing Date: 2025-03-07
Form Type: 10-K
Source: 0000950170-25-035507
Chunk: 21

Company: Atara Biotherapeutics, Inc.
Filing Date: 2025-03-07
Form: 10-K
Item: Item 1
Chunk 21
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 experience. These comparability data analyses were submitted to the EMA through our MAA filing. EMA stated in its assessment report issued following approval of the MAA for tab-cel by the EC that it considered comparability of the intended commercial product with the clinically used product to be shown. 

In May 2024, we filed the BLA with the FDA.  In July 2024, the FDA accepted the BLA submission and granted priority review with a Prescription Drug User Fee Act target action date of January 15, 2025. In January 2025, we received the Response Letter from the FDA regarding our BLA.  The Response Letter was solely related to observations as part of a standard pre-license inspection of a third-party manufacturing facility for EBVALLO.  The Response Letter did not identify any deficiencies related to the manufacturing process, the clinical efficacy, or clinical safety data in the BLA, and the FDA did not request any new clinical trials to support a potential approval of tab-cel.

In January 2025, the FDA placed a clinical hold on Atara’s active Investigational New Drug (IND) applications.  These INDs include the tab-cel program as monotherapy treatment for adult and pediatric patients two years of age and older with Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD).  The clinical hold is directly linked to inadequately addressed GMP compliance issues referenced in the Response Letter.  While ATA3219 drug product is manufactured at a separate facility, the starting materials used in its production are affected by the compliance issues at the same third-party facility referenced in the Response Letter. We are currently undertaking efforts to support this third-party manufacturer in addressing the FDA's requests to lift the clinical hold and to support resubmission of the BLA for tab-cel.

Tab-cel Multi-Cohort Study

In patients where previous treatments have failed, the objective response rates, including complete response, were 33.3% (three out of nine patients) in AID-LPD and 37.5% (three out of eight patients) in PID-LPD groups. Tab-cel was generally well-tolerated with a favorable safety profile consistent with previously published clinical studies. These clinical data demonstrated that tab-cel was 

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well-tolerated and showed encouraging clinical activity in this patient population, with objective response rates ranging from 50% (two out of four patients) to 80% (four out of