EsoBiotec reported extended follow-up on its in vivo BCMA CAR-T program ESO-T01 in relapsed/refractory multiple myeloma, with data updated through a maximum 15 months (ID: 4022394a218a8809). All patients developed dual-phase cytokine release syndrome (grades 1–3) and hematotoxicities (grade ≥3), while immune-effector cell-associated neurotoxicity occurred in one patient. The response rates remained high in the small cohort (objective response rate 100%), with durability limited by persistence observed as insufficient and relapse occurring with extramedullary involvement, underscoring the need for platform optimization (ID: 4022394a218a8809).