Gilead and Arcellx Highlight Multiple Myeloma Cell Therapy Safety, Initiate Phase 3 Dosing

Gilead and Arcellx have released encouraging data from their early trials on a new cell therapy for multiple myeloma, showing zero occurrences of certain delayed neurotoxicities. These neurotoxicities are often linked with another treatment known as Carvykti, developed by Johnson & Johnson and Legend Biotech. According to an abstract published before the upcoming American Society of Hematology (ASH) annual meeting in December, both the Phase 1 and Phase 2 studies of the investigational therapy, named anito-cel, revealed no cases of delayed neurotoxicity, cranial nerve palsies, Guillain-Barré syndrome, or Parkinsonian-like symptoms as of June 1.

This partnership between Gilead and Arcellx has drawn significant interest from investors, especially given Gilead's previous oncology projects have encountered multiple obstacles. Now, the first patient has been given a dose in their crucial Phase 3 trial named iMMagine-3. If anito-cel proves to be safer and just as effective, it could rival Carvykti, a potential blockbuster treatment from J&J and Legend that reported $286 million in sales last quarter. Notably, around 10% of patients on Carvykti experience movement neurotoxicities.

The Phase 2 trials of anito-cel included 58 patients who had already undergone a median of four different treatment regimens. With a median follow-up period of 10.3 months, 62% of these patients experienced complete remission of their cancer, and 95% showed a response to the treatment. The estimated progression-free survival and overall survival rates at six months were 90% and 95%, respectively.

Anito-cel, or anitocabtagene autoleucel, targets BCMA and has been developed specifically for treating multiple myeloma. Gilead and Arcellx aim to penetrate a market currently dominated by treatments like Carvykti and Bristol Myers Squibb’s Abecma. Despite the promising results, some side effects were noted in the Phase 2 data. Approximately 84% of patients experienced cytokine release syndrome (CRS), a severe side effect associated with immunotherapies. Most CRS cases were of low grade, though one patient succumbed to the syndrome. Additionally, there were two other deaths reported from retroperitoneal hemorrhage and fungal infection. Five patients experienced ICANS, another form of neurotoxicity related to immunotherapies, but all instances were resolved.

Gilead has declined to provide further comments, but updated results with extended follow-up periods are expected to be presented at the annual ASH meeting. The medical community and investors alike are closely watching the developments from this trial, as a successful outcome could significantly impact the treatment landscape for multiple myeloma, providing a potentially safer alternative to existing therapies while expanding options for patients battling this challenging cancer.