MagnetisMM‑3: Pausing Elranatamab Without Losing Response | Alexander Lesokhin, MD

So, my name is Alex Lasokan. I'm a myeloma specialist at Memorial Sloan Kettering in New York City. So, I'm going to be talking about our presentation on prolonged interruptions of L. ranatumab. This was a post hoc analysis of the magnetism 3 study. Magnetism 3 was a registrational study of L. ranatumab, which L. ranatumab is a BCMA CD3 bispecific T-cell engager. So, it binds myeloma cells, activates T-cells. Magnetism 3 had two cohorts, a BCMA exposed cohort and a BCMA naive cohort. In the patients that had not previously been treated with BCMA directed treatments, the overall response rate was 61% with a CR rate of 37%. The trial in both cohorts, individuals received step up dosing, then weekly dosing for six months and for those that continued to respond, they went on to every other week dosing and then after another six months of that, they had the option to go to monthly dosing. Throughout the study, patients had interruptions in their treatment. And so, this was a post hoc analysis of all 187 patients enrolled on that study for everyone who interrupted treatment for six months or more with follow-up data over that period of time. So this included 30 patients. The 30 patients that stopped mostly stopped for a variety of reasons, infection, fatigue. It's usually an adverse event. The median time to when they stopped treatment was about 13 months and the overall follow-up of patients after they had stopped was 18 months. And the striking finding was that responses deepened despite the fact that they stopped And approximately 77% of folks that had stopped treatment with 18 months of median follow-up remained in response and had not had recurrence, did not require additional therapy. Two patients restarted treatment and one of those patients did have a reappearance of a monoclonal protein that then subsequently disappeared. That's insufficient really to say whether or not you can re-challenge and re-treat or re-capture response. That needs additional study. But the overall take home point is that prolonged interruptions of L-Renatumab were feasible and safe and patients largely maintained their response, which I think is a very important observation for the patient population that receives BCMA directed by specific therapies.