Bispecific Antibody Safety Management and Shared Decision-Making

Dr. Nooka provides comprehensive guidance on bispecific antibody safety management, emphasizing the predictable chronology of adverse events. While bispecific antibodies can cause CRS and immune effector cell-associated neurotoxicity syndrome (ICANS) as immune responses, these toxicities occur at much lower grades compared to CAR-T therapy. The timing is highly predictable, occurring very early in treatment, allowing for methodical administration strategies to minimize patient risk.

Multiple management approaches exist for the initial treatment period, including prophylactic tocilizumab and steroids to minimize high-grade toxicities, enabling safe outpatient administration. Different centers employ varying strategies: some use steroids, others provide close monitoring, and some admit patients for observation. Regardless of approach, once the first 2 weeks pass, CRS and ICANS risks are substantially minimized, making these toxicities manageable rather than treatment-limiting factors.

Beyond the first month, infection risk and cytopenias become primary concerns, particularly with weekly dosing schedules. Key management strategies include systematic infection monitoring and prophylaxis with monthly intravenous immunoglobulins for all BCMA bispecific recipients. As these agents are highly B-cell depleting, patients develop hypogammaglobulinemia, significantly increasing infection risk. IVIG replacement therapy substantially reduces this complication.

Treatment holds for active infections are standard practice; patients should not receive dosing during infections, but responses are maintained during treatment delays. For neutropenic patients at high infection risk, growth factors are recommended and not contraindicated. Once patients achieve response, dosing interval extension should be considered to reduce continuous BCMA targeting while maintaining benefit and lowering infection risk.

Dr. Nooka emphasizes shared decision-making between physician and patient, discussing response rates, duration of response, associated risks, and commitment requirements for both bispecific and CAR-T options. Patient circumstances heavily influence decisions: caregivers with responsibilities cannot commit three months for CAR-T, whereas retired patients may prefer comprehensive treatment approaches. Most patients fall into the bispecific category, representing the safest method that does not interrupt caregiver responsibilities or job obligations, particularly relevant for younger patient populations with ongoing life commitments.