Timing of Bispecific Antibody Therapy After CAR T-Cell May Affect Outcomes Among Patients With R/R FL
Key Takeaways:
- Patients with follicular lymphoma (FL) who were treated with bispecific antibodies (BsAbs) following chimeric antigen receptor (CAR) T-cell therapy had a 1-year progression-free survival (PFS) rate and overall survival (OS) rate of 42% and 76%, respectively.
- Patients who received BsAbs within 6 months of CAR T infusion had worse outcomes than those who received BsABs after 6 months, indicating timing of treatment may influence health outcomes.
- These findings can be used to inform treatment decisions, although further research is needed to determine optimal therapy sequencing.
The approval of CAR T-cell and BsAb therapies for the treatment of relapsed or refractory (R/R) FL has greatly enhanced disease management strategies. However, optimal treatment sequencing remains unclear.
Researchers analyzed the impact of subsequent BsAb regimens among patients with FL who were previously treated with CAR T-cell therapy.
Patient Characteristics
In a real-world study of 136 patients with R/R FL who received CAR T-cell therapy between 2021 and 2024, 18 (13%) received subsequent BsAb treatment. Among these 18 patients, 15 received mosunetuzumab and 3 received epcoritamab.
The median interval between CAR T-cell infusion and BsAb initiation was 18.6 months, with 4 patients receiving BsAb therapy within 6 months of CAR T-cell therapy.
Clinical Response to BsAb Therapy
Subsequent BsAb therapy had an overall response rate (ORR) of 61% and a complete response rate (CRR) of 39%. The median time to best response was 2.6 months.
Patients who were treated with BsAbs within 6 months of CAR T infusion had worse outcomes than those who received BsAbs after 6 months of CAR T infusion. ORRs were 50% vs 64%, respectively, while CRRs were 0% vs 50%, respectively.
The median PFS was 6 months, and the 1-year PFS rate was 42%. The median OS was 23.6 months, and the 1-year OS rate was 76%.
Similarly, patients receiving BsAbs within 6 months of CAR T therapy had lower survival rates than those who were treated after 6 months of CAR T therapy. PFS was 3.4 months vs 12.2 months, respectively, while median OS was 16.2 months vs not reached.
Safety Profile
Of the 18 patients assessed, 7 died following BsAb initiation, 6 of which were related to relapse.
Nine patients experienced cytokine release syndrome (CRS), with all events being either grade 1 or grade 2. Five patients contracted infection, with most being grade 3 events.
Unplanned hospitalizations during BsAb therapy occurred with 8 patients: 4 for infection, 2 for CRS, 1 for infusion reaction, and 1 for other reasons.
Implications for Managed Care
In this study, patients with R/R FL achieved clinically significant, if short, responses to BsAbs following CAR T-cell therapy. Patients who received BsAb therapy within 6 months of CAR T infusion had poorer outcomes, suggesting timing may factor into treatment sequencing strategies.
The authors said, “Further research is warranted to elucidate how the sequencing of these therapies influences lymphoma biology, clinical outcomes, and patient-reported experience, thereby informing shared decision-making and optimizing treatment strategies for patients with R/R FL.”
Reference
Sharp J, Bhatta S, Huang JJ, et al. Real-world outcomes of bispecific antibody therapy after chimeric antigen receptor T-cell therapy in follicular lymphoma. Blood Cancer J. 2026. 16:96 doi:10.1038/s41408-026-01546-3
