Shares of Adaptimmune slid 12% yesterday morning after the company updated its TCR therapy to include fludarabine, which was linked to deaths in Juno’s CAR-T trials.
Despite optimism that T-cells are the key to cancer cures, the field has taken a number of hits this year. Most recently, the FDA put a partial hold on the clinical development of Adaptimmune‘s lead program last August after it proved ineffective in Phase I/IIa trials for a rare form of cancer. Adaptimmune is attempting to fix the problem by preconditioning future patients with fludarabine, the chemotherapeutic agent linked to the deaths in Juno’s CAR-T therapy trials.
In these trials, fludarabine was faulted for three fatal cases of cerebral edema and one of lethal neurotoxicity. Despite its infamy, John Carroll at Endpoints notes that fludarabine remains a “vital part of the preconditioning regimen” in cell therapies, because it allows cells to proliferate and kill off their cancerous counterparts. Indeed, Adaptimmune believes patients did not respond to its therapy as a result of omitting this drug and instead relying upon cyclophosphamide alone.