Basel, Switzerland, September 17, 2026
Roche has announced positive results from the Phase III CELESTIMO study, showing that a Lunsumio-based treatment regimen significantly improved progression-free survival (PFS) in people with relapsed or refractory follicular lymphoma who had previously received at least one line of treatment. The study evaluated Lunsumio® (mosunetuzumab) in combination with lenalidomide against MabThera®/Rituxan® (rituximab) plus lenalidomide. According to Roche, the trial met its primary endpoint at an interim analysis, demonstrating a statistically significant and clinically meaningful reduction in the risk of disease progression. The findings represent an important development in the ongoing clinical evaluation of Lunsumio in earlier lines of follicular lymphoma treatment.
Phase III CELESTIMO Study Shows Significant PFS Benefit
The CELESTIMO Phase III clinical trial is evaluating whether combining Lunsumio with lenalidomide can provide improved outcomes compared with the established rituximab and lenalidomide combination in patients with relapsed or refractory follicular lymphoma. Participants had received at least one previous line of systemic therapy. Roche reported that the study successfully achieved its primary endpoint at the interim analysis, with the Lunsumio-based regimen producing a significant improvement in progression-free survival. However, the company noted that overall survival data remained immature at the time of the interim analysis, meaning longer follow-up will be required before conclusions about overall survival can be drawn. The safety profile of Lunsumio plus lenalidomide was reported to be consistent with the known safety profiles of the individual medicines, with no new safety signals identified.
Lunsumio Expands Potential in Earlier-Line Treatment
Lunsumio is a CD20xCD3 bispecific antibody designed to engage the immune system against malignant B cells. The medicine simultaneously targets CD20 on B cells and CD3 on T cells, helping redirect the patient’s T cells toward cancer cells. Lunsumio is currently approved in multiple countries for adults with third-line or later relapsed or refractory follicular lymphoma, and Roche is investigating its use in earlier treatment settings and combination regimens. The CELESTIMO results support the company’s efforts to potentially expand Lunsumio into second-line or later follicular lymphoma.
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An additional feature of the regimen highlighted by Roche is its potential suitability for outpatient treatment. The company said the Lunsumio-based approach combines clinical activity with a tolerable safety profile and a relatively simple dosing schedule. Lunsumio is available through intravenous and subcutaneous formulations, providing flexibility in how treatment can be administered. Roche is continuing to evaluate the medicine across different stages and types of B-cell malignancies, including follicular lymphoma and diffuse large B-cell lymphoma.
Results Could Support Future Regulatory Submissions
The CELESTIMO study serves as a confirmatory trial for Lunsumio and is intended to support conversion of the existing accelerated approval or conditional marketing authorisation for Lunsumio monotherapy in third-line or later follicular lymphoma to full approval. The study also has the potential to support an indication in second-line or later follicular lymphoma. Following the positive interim findings, Roche said the data will be submitted to health authorities and presented at an upcoming medical meeting.
Follicular lymphoma is the most common slow-growing form of non-Hodgkin lymphoma and frequently follows a pattern of remission and relapse. As the disease progresses through successive relapses, treatment can become increasingly challenging. Roche’s latest Phase III findings therefore add to the clinical evidence surrounding bispecific antibody-based treatment strategies and combination therapies for relapsed or refractory disease. The company is also studying Lunsumio in earlier treatment settings, including the Phase III MorningLyte study in first-line follicular lymphoma.
Source: Roche press release
