Gilead, Arcellx touts CAR-T safety profile in multiple myeloma trial

California biotech Arcellx announced new positive data from its phase 2 pivotal study of anitocabtagene autoleucel (anito-cel) in patients with relapsed or refractory multiple myeloma, ahead of an oral presentation at the American Society of Hematology Annual Meeting.

Overall, preliminary results from the iMMagine-1 study demonstrate deep and durable responses with a predictable and manageable safety profile in a high-risk fourth-line or higher (4L+) RRMM population, including triple- and penta-class refractory disease.

Specifically, results from 86 patients demonstrated 97% overall response rate and 62% complete response/stringent complete response at a median follow-up of 9.5 months. Notably, no delayed neurotoxicities have been observed to date with anito-cel, including no Parkinsonism, no cranial nerve palsies, and no Guillain-Barré syndrome in more than 150 patients dosed across the phase 1 and iMMagine-1 studies.

“As a physician who treats many patients both inpatient and in the outpatient setting, the emerging safety profile of anito-cel is encouraging, in particular the absence of any delayed neurotoxicities reported to date. We are excited to begin enrolling patients in the iMMagine-3 study and in the near future having anito-cel as an approved treatment option,” said Ciara Freeman, M.D., Ph.D., assistant member, Department of Blood and Marrow Transplant and Cellular Immunotherapy, Moffitt Cancer Center, in Arcellx’s press release.

Market analysts pointed out that differentiating itself on safety could help anito-cel take on rival CAR-T, Carvykti, developed by Legend and J&J and approved in 2022.

Anito-cel is the first BCMA-directed CAR-T cell therapy to be investigated in multiple myeloma that utilizes Arcellx’s novel and compact binder known as the D-Domain. According to Arcellx, the small, stable D-Domain binder enables high CAR expression without tonic signaling and is designed to quickly release from the BCMA target. This combination may allow for the effective elimination of multiple myeloma cells without severe immunotoxicity.

Arcellx formed a global strategic collaboration and license agreement to co-develop and co-commercialize anito-cel for patients with relapsed and/or refractory multiple myeloma with Gilead’s Kite in December 2022, expanding it a year later to include the license for Arcellx’s multiple myeloma program and propel treatment of lymphomas.

Per the deal, Kite and Arcellx will jointly commercialize the anito-cel asset in the U.S. and Kite will commercialize the product outside the U.S.