A NEW retrospective study, presented at the recent 2025 COMy (Controversies in Multiple Myeloma) Congress, has highlighted a high incidence of infections in individuals with relapsed or refractory multiple myeloma treated with bispecific antibodies (BsAbs) targeting CD3/BCMA and CD3/GPRC5D.
The analysis included 31 individuals who had received at least three months of BsAb therapy, with some exposed to sequential treatment involving both targets. The median age was 68, and participants had received multiple prior lines of therapy, including autologous transplant in over a third of cases.
Across a total of 389 months of exposure (median 10.9 months per person), 64 infectious episodes were reported in 84% of the cohort, representing an incidence of 0.19 infections per patient month. Nearly half of the infections were respiratory (47%), with others involving the bloodstream (17%), gastrointestinal tract (15%), or varied sites (21%). No fatal infections were reported, although 26% were grade 3 or 4 in severity.
Despite routine prophylaxis, including antivirals, anti-pneumocystis agents, and immunoglobulin replacement, infection rates remained high. Etiological agents were identified in 51% of episodes, with pathogens ranging from bacteria (45%) and viruses (45%), such as SARS-CoV-2, cytomegalovirus, and JC virus, to occasional fungal infections.
Notably, no specific patient or disease characteristics such as myeloma subtype, number of prior therapies, or prior transplant were statistically linked to increased infection risk in this small cohort.
The findings highlight the need for ongoing surveillance, larger studies, and clearer guidelines to reduce infectious complications associated with BsAb therapies in this population.
Reference
Seganfredo FB et al. Infectious risk of relapsed/ refractory multiple myeloma patients treated with bispecific antibodies. COMy 2025.
