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.

When choosing a bispecific antibody for follicular lymphoma, a major practical difference is the treatment duration. Mosunetuzumab is a time-limited therapy stopped after achieving a complete response, while Epcoritamab is given indefinitely until progression. This distinction heavily influences selection, especially for elderly patients.

The phase 3 INMIND trial showed adding tofacitimab to lenalidomide and rituximab (R-squared) significantly improves progression-free survival over R-squared alone. This fixed-duration regimen with a manageable toxicity profile is now considered a new standard of care for this patient population, including high-risk subsets.

Beyond approving the triplet combination, the positive Epcor FL1 trial data had a significant ripple effect. It solidified the drug's overall profile, leading to the conversion of its prior provisional (accelerated) approvals for monotherapy in follicular lymphoma and DLBCL into full, traditional approvals.

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.

Not all CD20-targeting bispecifics can be combined with rituximab. Mosunetuzumab binds the same epitope, causing competition. However, glofitamab and epcoritamab bind different epitopes, allowing for logical and potentially synergistic combinations with rituximab-based regimens.

When choosing between novel combinations in relapsed follicular lymphoma, a logical strategy is to use tafasitamab-lenalidomide-rituximab (Tafa-R2) first. After progression, single-agent epcoritamab remains highly effective. The reverse is not true, as tafasitamab monotherapy would not be effective after epcoritamab-R2 failure, making the initial choice critical.

As CAR-T cell therapies are increasingly adopted for second-line treatment of large cell lymphoma, epcoritamab is solidifying its role as a critical, potentially curative replacement option in the third-line setting. This establishes a clear sequential treatment pathway for patients who continue to relapse.

The regimen's profound success in relapsed/refractory patients is not an endpoint, but a launchpad. It provides the rationale for the ongoing Epcor FL2 trial, which directly challenges standard chemoimmunotherapy and could establish a chemotherapy-free, bispecific-based combination as the new first-line standard of care.