An off-the-shelf CAR-T cell therapy being developed by CRISPR Therapeutics saw positive results in some patients with advanced B-cell lymphoma, but was also tied to a patient's death, the drugmaker said Oct. 21.
Off-the-shelf CAR-T drugs are derived from T cells provided by healthy donors and are supposed to be less dangerous than traditional CAR-T therapies, which are made from patients' own immune cells.
In a clinical trial testing CRISPR's treatment, called CTX110, 11 patients with advanced B-cell lymphoma were injected with the drug. Four patients saw complete responses, meaning tumor cells were no longer detectable, according to STAT.
The patient given the highest dose, which was 600 million cells, was hospitalized with a high fever, signs of infection, memory loss and confusion. The patient's neurotoxicity deteriorated despite treatment, and he died 52 days after receiving the CAR-T drug. His physician classified the death as related to the CTX110 treatment, STAT reported.
A second patient also reported neurotoxicity, which is a known side effect of CAR-T therapy, but it was mild and improved with treatment. Three patients also developed moderate cytokine release syndrome, which is an immune-based side effect often associated with CAR-T drugs, according to STAT. The cases were resolved with treatment.
CRISPR reported positive results in patients treated with 300 million-cell doses of CTX110. Two patients with that dose had complete responses, and the patients are still in remission. Four patients had complete responses across all dose levels.
In August, the FDA halted San Diego-based drugmaker Poseida Therapeutics' clinical trial of a CAR-T therapy after a patient died. In July, the agency put a clinical hold on French drugmaker Cellectis' trial for its off-the-shelf CAR-T therapy after a patient died of cardiac arrest.