Azer-cel Shows Safety in Progressive MS Trial
A phase I study of an off-the-shelf CAR T cell therapy found no serious dose-related adverse events in 18 adults with progressive multiple sclerosis.
Updated on Nov. 6, 2026 in Alzheimer’s
Data from a phase I trial of azercabtagene zapreleucel (azer-cel) were presented on 21-23 October 2026 at MSToronto2026 in Toronto, Canada. The open-label study found the therapy was safe, and most participants remained stable or improved on biomarker and clinical measures.
Why it matters
Progressive multiple sclerosis has limited treatment options, and the trial suggests an allogeneic anti-CD19 CAR T cell approach may be tolerable in this population. The researchers conclude the findings support further investigation of azer-cel in progressive multiple sclerosis.
The phase I study enrolled 18 adults and tested doses from 30 to 500 million CAR T cells, with a median follow-up of 102 days. The open-label design includes no comparator group, and longer-term durability of the reported stability has not been established.
The details
Participants with refractory progressive multiple sclerosis first underwent lymphodepletion, then received a single infusion of azer-cel, an off-the-shelf allogeneic anti-CD19 CAR T cell therapy designed to deplete peripheral B cells and induce immune reconstitution. Most participants remained stable or showed improvement on cerebrospinal fluid biomarker analyses and clinical disability measures, with no serious dose-related adverse events evident.
Timeline
21-23 October 2026: Data presented at MSToronto2026 in Toronto, Canada.
102 days: Median follow-up period for trial participants.
Health Landscape
The trial extends CD19-directed CAR T cell approaches, already studied in B-cell malignancies, into progressive multiple sclerosis, a condition with limited options. Its off-the-shelf allogeneic design is intended to avoid the patient-specific manufacturing that has constrained earlier autologous CAR T programs.
For people living with progressive multiple sclerosis, the trial reports no serious dose-related adverse events at the tested doses, though the study was small and open-label. Any future access would depend on later-phase trials, and no treatment availability is established by these results.
The takeaway
Early safety data support continued study of CD19-directed off-the-shelf CAR T therapy in progressive multiple sclerosis. Readers should treat the findings as preliminary, since the trial enrolled 18 people without a control group.
Further reading
For more on neurological disease research, see Alzheimer’s coverage.
Source note: This article includes information reported by Nature.
