FDA halts Allogene CAR T trial after safety scare

Oct. 8, 2021

The U.S. FDA has put a hold on Allogene Therapeutics’ AlloCAR T clinical trials following a report of a chromosomal abnormality in a single patient.

The clinical hold follows San Francisco-based Allogene's notification to the FDA that a chromosomal abnormality was detected in a bone marrow biopsy of a study patient with Stage IV transformed follicular lymphoma.

According to the biotech, following infusion of ALLO-501A, the patient experienced a reaction that required a course of high dose steroid therapy. The patient subsequently developed progressive pancytopenia and a bone marrow biopsy showed aplastic anemia and the presence of ALLO-501A CAR T cells with the chromosomal abnormality.

An investigation is underway to further characterize the observed abnormality, including any clinical relevance, evidence of clonal expansion, or potential relationship to gene editing.

The worst case scenario could have broad implications for the off-the-shelf T-cell therapy space. The chromosomal abnormality raises the possibility that the gene editing process could disrupt a cell's genome and make them capable of causing damage.

Allogene expects to provide additional updates in the coming weeks following consultation with the FDA.

Read the press release