FDA-approved fulvestrant-induced CAR phase separation enables precise control of CAR T antitumor function.

Fulvestrant-induced iPhase-CAR T cells achieve precise, reversible control of antitumor activity, enhancing efficacy while minimizing side effects.

• Why it matters: Controlling CAR T cell signaling is critical to prevent dysfunction, exhaustion, and severe side effects like cytokine storms, yet current methods lack precise regulation.
• What they did: Researchers engineered an FDA-approved drug-inducible phase-separation system (iPhase-CAR) by integrating an estrogen receptor α (ERα) mutant with fulvestrant to enable reversible CAR clustering on T cells.
• The result: iPhase-CAR T cells exhibit superior antitumor responses with tunable activity controlled by fulvestrant, paving the way for safer, more effective CAR T therapies.