Monitoring Late CAR T Toxicities and Treating High-Risk Myeloma Earlier

Matthew J. Frigault, MD, clinical director of the Cellular Immunotherapy Program at Mass General Brigham Cancer Institute, explained that some toxicities of CAR T-cell therapy emerge within the first 30 days, while others can appear 90 days or later after infusion. Because many of these events, especially infections, can be managed locally, he emphasized ongoing communication between the treating center, community sites, and families rather than requiring patients to travel long distances.

Frigault advised that any personality changes, neurologic symptoms, weaknesses, sensory changes, or new-onset diarrhea should prompt a discussion with the treating center, as clinicians are increasingly able to reverse serious complications with early intervention. He added that greater familiarity with these toxicities in community practice will be essential to broadening access.

Adam D. Cohen, MD, director of Myeloma Immunotherapy and professor of medicine at the Hospital of the University of Pennsylvania, then addressed patients with high-risk features, including extramedullary disease, high-risk cytogenetics, and functional high risk, defined as progression within roughly 18 to 24 months of initial therapy. These patients may still fare worse than those with standard-risk disease, Cohen said, but they have better outcomes with CAR T-cell therapy or bispecific antibodies compared with historical findings with triplet regimens built on anti-CD38 antibodies, immunomodulatory drugs (IMiDs), or proteasome inhibitors. He recommended moving these patients to T-cell–directed therapy early before disease becomes more refractory and harder to control during bridging, acknowledging that high-risk multiple myeloma remains an unmet need.