Today’s autoimmunity drugs suppress the immune system in different ways. Even when they control symptoms well, patients generally must take them for life and can be left vulnerable to infections.

CAR-T therapy works very differently. It was originally developed for leukemias and lymphomas caused when the immune system’s B cells turn cancerous – and the breakthrough treatment wiped them out.

Lupus, multiple sclerosis, rheumatoid arthritis, myositis and many other autoimmune diseases are fueled by B cells going awry in a different way: They start making antibodies that attack the body instead of protecting it.

How it works: Different immune soldiers called T cells are filtered out of a patient’s blood and sent to a lab, where they’re programmed to destroy their B cell relatives – both autoreactive ones and healthy ones that might eventually run amok. Millions of copies of those “living drugs” are grown and, after the patient has chemotherapy to make room, infused back to get to work.

"The immune system is reset to a time before it was attacking your own body," said Dr. Amit Saxena at NYU Langone Health.

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