FDA lifts clinical hold on Gilead's CAR-T as Arcellx sheds light on reason for patient death

Gilead Sciences' $225 million bet on Arcellx’s CAR-T cell therapy is back in play after the FDA lifted a clinical hold instigated in the wake of a patient death.

The trial pause has been very short, with the regulator only implementing the hold on the iMMagine-1 study in June. At the time, Arcellx said it believed a contributing factor in the fatality had been “limitations on bridging therapy,” a term for the treatments given in the period between the T cells being removed from a patient’s body and the CAR-T being infused.

In a postmarket release yesterday, the biotech revealed that the individual in question had in fact become ineligible for treatment under the trial protocol prior to receiving the anti-BCMA therapy. “Subsequently, the patient was managed in a manner that conflicted with the trial protocol,” Arcellx added.

To allow the phase 2 study to continue, the FDA has not only signed off on an updated trial protocol but has agreed to an expanded range of bridging therapies, which Arcellx’s CEO Rami Elghandour said “better aligns our protocol with current clinical practice.”

"We have worked closely with FDA to expeditiously resolve the clinical hold and we thank them for their collaboration and dialogue throughout this process," Elghandour said in the release.

Even while the hold was in place, the FDA allowed the 17 patients who had been enrolled in the trial but not yet dosed to receive the CAR-T therapy, dubbed CART-ddBCMA, the CEO noted.

With the hold now lifted, the biotech expects to present preliminary data from the iMMagine-1 study in the second half of 2024 with an estimated commercial launch for CART-ddBCMA penciled in for 2026. Allowing Arcellx to get back on track with the pivotal study will be good news for Gilead, which has a lot riding on the trial.

Gilead’s Kite Pharma cell therapy unit secured the rights to co-develop and co-commercialize the therapy with Arcellx late last year. By handing over $225 million in upfront cash along with a $100 million investment in the biotech, Gilead secured itself a spot as a potential rival to BCMA front-runners like Carvykti developers Johnson & Johnson and Legend Biotech as well as Abecma makers Bristol Myers Squibb and 2seventy bio.