Three-year data for odronextumab, given until progression in follicular lymphoma, reveals a high rate of severe (Grade 3+) infections (45%), including fatal events. This highlights a critical safety concern with continuous dosing and strengthens the clinical argument for using fixed-duration bispecific regimens to mitigate long-term toxicity.

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The phase 3 EPCOR FL-1 trial showed that adding epcoritamab to the lenalidomide/rituximab (R-squared) backbone profoundly improved progression-free survival in relapsed follicular lymphoma. Presented as the most important FL abstract at ASH, this result is expected to establish a new standard of care in this setting.

A novel trial design used mosinutuzumab monotherapy first in frontline follicular lymphoma, adding lenalidomide only for patients without a complete response. This adaptive approach successfully spared about two-thirds of patients from the added toxicities of lenalidomide while still achieving very high overall efficacy.

Although continuous BTK inhibitors have the most prospective data for high-risk CLL (17p/TP53 mutations), some highly motivated patients still opt for fixed-duration treatment. This requires a detailed conversation where clinicians must explain the trade-off: achieving a treatment-free period may come at the cost of needing second-line therapy sooner.

With highly effective CLL therapies, primary causes of mortality are now infections and secondary cancers from immunodeficiency. Research is now focusing on immune reconstitution after treatment, marking a pivotal shift towards managing long-term survivorship challenges beyond just controlling the leukemia itself.

In follicular lymphoma, the treatment goal is durable remission with manageable toxicity, not necessarily a cure. Therefore, clinicians frequently prefer using a bispecific antibody first, reserving the more complex and toxic CAR-T cell therapy for transformed disease or after a bispecific fails.

Despite strong single-agent trial results, experts believe the field is shifting away from continuous monotherapy. The most significant future impact for pirtobrutinib will likely be as a backbone of fixed-duration combination therapies with drugs like venetoclax, aiming for deeper remissions without indefinite treatment.

To manage hypogammaglobulinemia from bispecific antibodies, clinicians are adopting a more proactive approach. Following the model from myeloma care, they are initiating IVIG therapy earlier to prevent infections, rather than waiting for recurrent infections to occur as was standard with rituximab.

While many CLL patients prefer fixed-duration therapy to avoid continuous medication, this preference is often overridden by practical logistics. The burden of increased monitoring and frequent clinic visits associated with fixed-duration regimens leads some patients to opt for continuous therapy instead.

Recent non-inferiority trials affirm that fixed-duration combination therapies are viable alternatives to continuous BTK inhibitors. However, clinicians must look beyond the headline conclusion, as numerical data can show slightly worse progression-free survival for high-risk subgroups within the acceptable non-inferiority margin, complicating treatment decisions.

Long-term follow-up from the pivotal epcoritamab trial reveals that 46% of DLBCL patients who achieve a complete remission maintain it at four years. This durability provides strong evidence that bispecific monotherapy, not just CAR-T, can be a curative treatment for a subset of patients.

Continuous Bispecific Therapy in Follicular Lymphoma Poses Significant Long-Term Infection Risk | RiffOn