The wave of excitement around using CAR-T cell therapy for autoimmune disease just hit a note of caution: Novartis and Bristol Myers Squibb have paused autoimmune CAR-T trials after cases of a rare, potentially life-threatening immune reaction.
Novartis halted trials of its therapy rap-cel across multiple autoimmune indications (including lupus, myasthenia gravis and multiple sclerosis) after identifying three cases of immune effector cell-associated hemophagocytic syndrome (IEC-HS) — described as a rare and possibly life-threatening reaction. Bristol Myers Squibb voluntarily paused enrollment in trials of zola-cel after detecting “transient and reversible inflammatory events,” including one prior IEC-HS case. Novartis began its holds on August 24 and is engaging with regulators; BMS acted “out of an abundance of caution.”
What might be driving it
Analysts flagged a possible culprit: the accelerated cell-production technology used in these next-generation therapies “could be driving increased cell expansion and the reported toxicities,” noted William Blair’s Sami Corwin — adding that this “will clearly need to be monitored” for its impact on adoption.
Why it matters
CAR-T has produced striking results in autoimmune disease — including recent reports of drug-free remission in rheumatoid arthritis and lupus — raising hopes for an immune “reset.” These pauses are a reminder that repurposing a powerful cancer therapy for non-cancer patients carries real safety questions. Other developers (Cabaletta Bio, Kyverna) are continuing their programs, so the field isn’t stopping — but the risk-benefit balance for autoimmune patients will get closer scrutiny.