Bristol-Myers Squibb Shares Fall After Patient Dealth in Phase 1 Breakfree-2 Multiple Sclerosis Study

12:48 PM EDT, 10/23/2026 (MT Newswires) -- Bristol-Myers Squibb (BMY) shares were down 2% after the company said Friday that a patient with highly active relapsing multiple sclerosis in the phase 1 breakfree-2 study evaluating zolacabtagene autoleucel died from septic pneumonia after receiving high-dose cyclophosphamide. The patient died a day after developing the infection, 44 days after the infusion of zola-cel, an investigational, autologous CD19-directed CAR T cell therapy, the company said. The study included 66 patients, 30 with highly active relapsing multiple sclerosis and 36 with progressive forms of multiple sclerosis, with ongoing disease activity or worsening disability despite treatment. The primary endpoint of the study was safety, and efficacy was the secondary endpoint, the company added. Bristol-Myers said the data shows a safety profile consistent with prior phase 1 clinical trial data and promising efficacy across both haRMS and PMS, with all patients treated at dose level 2 remaining off disease-modifying therapies. Price: 61.66, Change: -1.35, Percent Change: -2.13