Bristol Myers Squibb disclosed that a patient died after receiving its investigational autoimmune CAR-T therapy in a Phase 1 trial in multiple sclerosis. The company said the patient’s motor symptoms did not resolve with standard autoimmune treatments, then developed septic pneumonia after administration of an immunosuppressant, and subsequently died. The disclosure adds to a growing pattern of safety events in autoimmune CAR-T programs, including pauses and new concerns reported by other developers in similar settings. BMS characterized the incident as part of the broader safety surveillance process while also continuing the program. For the industry, the incident is a reminder that autoimmune CAR-T introduces distinctive risks beyond oncology, where immune activation can produce severe inflammatory complications. Regulators and sponsors are likely to expect tighter mechanistic monitoring, rapid management pathways, and clearer stopping rules as autoimmune indications expand.