Roche reports that Lunsumio plus lenalidomide significantly improved progression-free survival in relapsed or refractory follicular lymphoma in Phase III CELESTIMO.
Written By: Charvi Kalal, PharmD
Reviewed By: Pharmacally Editorial Team
Roche reported that the Phase III CELESTIMO trial (NCT04712097) met its primary endpoint at interim analysis, demonstrating a statistically significant and clinically meaningful reduction in the risk of disease progression or death, as assessed by an Independent Review Committee (IRC), with Lunsumio plus lenalidomide compared with rituximab plus lenalidomide.
The trial enrolled patients with relapsed or refractory (R/R) follicular lymphoma (FL) who had received at least one prior line of systemic therapy. Overall survival (OS) data remained immature at the interim analysis, and the company has not reported an OS benefit.
Roche has not yet disclosed detailed PFS results, including the hazard ratio, median PFS or event counts. The full findings are expected to be presented at an upcoming medical meeting.
Lunsumio Redirects T Cells Against Malignant B Cells
Lunsumio (mosunetuzumab) is a CD20xCD3 T-cell-engaging bispecific antibody that binds CD20 on B cells and CD3 on T cells. By engaging both cell types, the antibody recruits and activates T cells to eliminate malignant B cells.
Lunsumio is administered for a defined treatment duration in its approved follicular lymphoma setting. The combination with lenalidomide adds an immunomodulatory agent to the T-cell-engaging antibody, creating a two-drug regimen for patients whose disease has returned or failed to respond to previous treatment.
Follicular lymphoma is the most common indolent form of non-Hodgkin lymphoma. Although the disease often responds to treatment, patients commonly experience periods of remission followed by relapse. Treatment can become more challenging with successive lines of therapy, particularly in patients with early disease progression.
Safety Profile Remains Consistent
The safety profile of Lunsumio plus lenalidomide was consistent with the known safety profiles of the individual study medicines, with no new safety signals identified at the interim analysis.
Roche also highlighted the potential practical advantages of the regimen, including outpatient administration and a simple dosing schedule. Lunsumio is available through both intravenous and subcutaneous administration, providing flexibility in treatment delivery.
CELESTIMO is evaluating the combination in patients receiving treatment in the second-line or later setting after at least one prior systemic therapy. The results therefore provide clinical evidence for evaluating mosunetuzumab-based treatment earlier in the follicular lymphoma treatment sequence.
Confirmatory Trial Could Expand Lunsumio Use
CELESTIMO has an important regulatory role for Lunsumio. The study serves as the confirmatory trial required to convert the accelerated approval in the US and conditional marketing authorisation in other jurisdictions for Lunsumio monotherapy in third-line or later follicular lymphoma into full approval.
The study also supports a potential indication for Lunsumio plus lenalidomide in second-line or later disease.
Levi Garraway, MD, PhD, Roche’s Chief Medical Officer and Head of Global Product Development, said the CELESTIMO findings indicate that a two-drug outpatient Lunsumio regimen could provide an effective treatment option earlier in the course of relapsed or refractory follicular lymphoma.
Regulatory Submissions Planned
Roche plans to submit the CELESTIMO findings to health authorities and present detailed results at an upcoming medical meeting.
The company is also evaluating Lunsumio across additional B-cell malignancies and treatment settings. In follicular lymphoma, the Phase III MorningLyte study is investigating Lunsumio plus lenalidomide in the first-line setting.
Lunsumio is currently approved for third-line or later R/R follicular lymphoma in more than 60 countries and, according to Roche, has been used to treat more than 3,800 patients. The CELESTIMO findings add Phase III evidence to the ongoing evaluation of mosunetuzumab-based therapy in earlier lines of follicular lymphoma.
Reference
Roche’s Lunsumio-based regimen significantly improves progression-free survival in follicular lymphoma in phase III CELESTIMO study, Roche, 17 September 2026
A Study Evaluating the Efficacy and Safety of Mosunetuzumab in Combination with Lenalidomide in Comparison to Rituximab in Combination with Lenalidomide with a US Extension of Mosunetuzumab in Combination with Lenalidomide in Participants with Follicular Lymphoma (Celestimo), ClinicalTrials.gov ID NCT04712097
About the Writer
Charvi Kalal (LinkedIn) is a Pharm.D intern and aspiring medical writer with hands-on experience in medical writing, clinical research, pharmacovigilance, and clinical pharmacy. She has experience in medical content writing through CliMed, along with exposure to ADR monitoring, prescription analysis, patient counselling, literature review, and research documentation. Her research focuses on ADR monitoring and reporting in breast cancer patients receiving targeted therapy. With certifications in GCP, biomedical research, scientific writing, and clinical research, she is passionate about transforming scientific evidence into accurate, engaging, and accessible healthcare content.