The FDA is now investigating 22 cases of blood cancer developing after CAR-T cell therapy treatment, said Marks, the director of the FDA’s Center for Biologics Evaluation and Research, on Monday at an Alliance for Regenerative Medicine event. “Although sequencing is not available for all of them, in at least a few of the cases we know that the CAR construct is in the malignant clone, which really suggests that there was probably an association there,” Marks said.
“And the onset of these was soon enough after the administration, in some cases, that it does look like there’s a causal relationship,” he continued.
The FDA announced in November that it was reviewing the safety of CAR-T therapies after reports of some cancer patients developing a second blood cancer following treatment. In December, the agency added a warning label on secondary cancers to Carvykti, a CAR-T cell therapy developed by Legend Biotech and Johnson & Johnson for multiple myeloma.
But as clinicians and cell therapy experts have said previously, Marks was keen to emphasize that the regulatory agency still believes the benefits of these treatments outweigh the safety risks.
That includes not only approved indications in blood cancers, but clinical trials in autoimmune diseases as well, where impressive early results have jolted the field’s interest.
“Where we are settling out is that, in general, the risk benefit is still going to be favorable to move forward in those development plans,” Marks said. “And that’s in part because autoimmune diseases are not benign diseases. Anyone who’s ever known somebody who’s had lupus cerebritis or lupus nephritis will know that those are potentially lethal diseases.
“Those development programs can and should continue. We may ask for some additional safety monitoring, more to come on that,” Marks continued.

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