Ribox Therapeutics received FDA IND clearance for RXIM-002, a circular RNA (circRNA)-based in vivo CAR-T program delivered via a targeted lipid nanoparticle (tLNP). The company plans to run a Phase I trial in patients with autoimmune cytopenias, including relapsed or refractory immune thrombocytopenia. Ribox’s approach aims to use circRNA to drive CAR-T activity in vivo, with the tLNP serving as the delivery vehicle. The clearance advances the program from regulatory preclinical review into first-in-human assessment of safety and early activity. This IND milestone fits a broader pipeline push for “in vivo” cellular therapies, where delivery, biodistribution, and immune activation control become central development questions.