Allogene's 5 CAR-T trials back on after October safety scare drew FDA hold

Allogene Therapeutics can resume five CAR-T clinical trials after an investigation found that a safety scare last fall was not linked to its gene editing or manufacturing process.

The FDA ordered a hold to all five trials in October when an abnormality was discovered in Allogene's trials that could potentially cause cancer. One patient was found to have experienced a reduction in all blood cell lines after receiving the biotech's anti-CD19 CAR-T candidate ALLO-501A. A biopsy discovered anti-CD19 CAR-T cells with a chromosomal abnormality.

But now, Allogene says the chromosomal abnormality found in the heavily pretreated patient with lymphoma was not observed in any of the company's AlloCAR T products and had no clinical significance, according to a Monday statement

Allogene's shares dropped 10% after the news that the FDA had lifted its hold, to $12.10 apiece as of 11:36 a.m. ET Monday. Prior to the clinical hold in October, Allogene's shares were above $24 but fell to below $17. 

RELATED: FDA stops all Allogene's CAR-T trials over safety scare, raising questions about future of gene editing

Allogene's five clinical trials include phase 1 studies in relapsed or refractory non-Hodgkin lymphoma with ALLO-501 and ALLO-501A, relapsed or refractory multiple myeloma with ALLO-715 and ALLO-605, and renal cell carcinoma with ALLO-316. The company will work with the clinical trial investigators to swiftly get the programs back on track. 

The abnormality was not found in any other patient treated with the same lot of ALLO-501A nor in any manufactured AlloCAR T product, Allogene said. The abnormality happened after the cell product was administered to the patient. 

In addition to the five trials, the South San Francisco biotech now plans to start a pivotal phase 2 trial of ALLO-501A in relapsed/refractory large B cell lymphoma in the middle of this year. The study start is pending final discussions with the FDA, Allogene said.