Autoimmune diseases like myasthenia gravis have long forced patients to trade daily function for chronic immunosuppression, but Cartesian Therapeutics is betting that its experimental RNA‑engineered CAR T cells can rewrite that equation. The company’s lead experimental therapy, Descartes‑08, is designed to deliver deep, durable remissions through a short course of outpatient infusions that selectively eliminate the plasma cells driving disease, while sidestepping the toxicity and logistical hurdles of conventional DNA‑based CAR T therapies. We spoke to Carsten Brunn, CEO of Cartesian Therapeutics, about how the company’s RNA‑engineered CAR T cells target the root cause of autoimmune diseases, data from its phase 2 study in myasthenia gravis, and the potential to expand the approach into myositis and other rare autoimmune indications.