Novartis halts CAR-T trials after three deaths

Three patients enrolled in a Novartis autoimmune disease trial died. Their immune systems overreacted to a cell therapy meant to help them, not harm them. Novartis has now paused eight trials of the treatment. Bristol Myers Squibb, working on a similar therapy, paused its own trials too, as a precaution.

Doctors call this treatment CAR-T therapy. It works by taking a patient's own immune cells and re-engineering them to hunt down a specific target. The cells then get infused back into the patient. It already works as a cancer treatment. Companies have been racing to adapt it for autoimmune diseases like lupus, where the immune system attacks the body itself. The idea is to reset a misfiring immune system, but resetting it is a violent process. Push too hard, and the same power that kills disease can turn on the patient.

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Does this stall the whole autoimmune CAR-T field, or just these two companies' programs? Novartis hasn't said how long the pause will last. It hasn't linked the deaths to a specific design flaw yet, either. Other companies chasing the same approach will be watching closely. A single bad readout can freeze an entire subfield until regulators and scientists figure out what went wrong.