Treatment of early relapse follicular lymphoma with mosunetuzumab

Phase II Multicenter Clinical Trial: Mosunetuzumab for Early Relapse of Follicular Lymphoma in the Nordic Countries

Phase 2 Interventional Oslo University Hospital · NCT05849857

This study is testing if a new treatment called mosunetuzumab can help adults with follicular lymphoma who have had a relapse within two years feel better and live longer compared to standard treatments.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years and up
SexAll
SponsorOslo University Hospital Academic / other
Drugs / interventionsrituximab, obinutuzumab, mosunetuzumab, chemotherapy, methotrexate, cyclophosphamide, immunotherapy, radiation, doxorubicin
Locations3 sites (Helsinki and 2 other locations)
Trial IDNCT05849857 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the efficacy of mosunetuzumab, a bispecific antibody, in adult patients with follicular lymphoma who experience relapse or progression within 24 months of their first-line treatment. Participants will receive weekly injections of mosunetuzumab for the first three doses, followed by treatments every three weeks for up to a year, depending on their response as evaluated by PET-CT scans. The primary goal is to determine if this new immunotherapy improves progression-free survival compared to standard second-line treatments for patients at high risk of poor outcomes.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with follicular lymphoma who have relapsed or progressed within 24 months of initial treatment.

Not a fit: Patients who have not experienced relapse or progression within 24 months of their first-line treatment may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve outcomes for patients with early relapse follicular lymphoma.

How similar studies have performed: Previous studies have shown promising results with bispecific antibodies in treating B-cell lymphomas, suggesting potential success for this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Written informed consent according to ICH-GCP guidelines.
2. Age ≥ 18 years.
3. Follicular lymphoma grade 1-3a with a current relapse or progression within 24 months of starting 1st line treatment or refractory to 1st line treatment (POD24), more specifically:

   1. Documented current relapse or progression of FL within 24 months of starting first line treatment containing a monospecific anti-CD20 antibody (such as rituximab or obinutuzumab with or without chemotherapy, small molecular inhibitors or immunomodulating agents such as lenalidomide).
   2. Current lack of response/refractoriness to first line treatment, i.e., no objective response or documented progression within 6 months following at least four cycles of monotherapy with a monospecific anti-CD20 antibody (such as rituximab 375mg/m2 iv or 1400 mg SC or equal) or following at least three cycles of a monospecific anti CD20 antibody combined with chemotherapy, small molecular inhibitors or immunomodulating agents such as lenalidomide.
   3. Received one prior treatment line of systemic therapy.
   4. Patients may have had a period of watch and wait before the initiation of first line treatment.
   5. Patients may have received localized radiotherapy previously.
4. At least one two-dimensionally measurable lesion with a longest diameter \>15mm.
5. WHO performance status 0-2. Patients with reduced WHO performance status (\> 2) can be considered if reduction in performance is caused by the lymphoma as determined by the investigator.

Exclusion Criteria:

1. Received 2 or more previous treatment lines.
2. Grade 3b FL.
3. CD20-negative lymphoma.
4. CNS involvement (current or previous).
5. Impaired bone marrow function (neutrophils \< 1.0 x 109/L or platelets \< 50 x 109/L) unless due to lymphoma involvement.
6. Severe cardiac disease: impaired cardiac function (NYHA class III or IV), myocardial infarction within the last 6 months, unstable arrythmias and/or unstable angina pectoris.
7. Impaired liver function not caused by lymphoma, defined as serum total bilirubin ≥ 1.5 x ULN (unless elevated due to Gilbert's syndrome) or serum ALT and AST \> 3 x ULN.
8. Impaired renal function not caused by lymphoma, defined as calculated creatinine clearance ≤ 40 ml/minute.
9. Other major organ dysfunction not caused by lymphoma.
10. Known history of drug induced liver injury, chronic active hepatitis C (HCV), chronic active hepatitis B (HBV), alcoholic liver disease, primary biliary cirrhosis, on-going extra-hepatic obstruction caused by cholelithiasis, cirrhosis of the liver or portal hypertension.
11. Active severe infection.
12. Hepatitis B (HBV) or hepatitis C (HCV) infection: Subjects with a previous hepatitis B infection will be eligible if they are negative for HBV-DNA; these subjects must be given prophylactic antiviral therapy. Subjects with a previous HCV infection will be eligible if they are negative for HCV-RNA.
13. Known or suspected chronic active Epstein-Barr virus (EBV) infection.
14. Received systemic immunosuppressive medications (including but not limited to cyclophosphamide, azathioprine, methotrexate, thalidomide, and anti-tumor necrosis factor agents) within two weeks prior to the first dose of mosunetuzumab.
15. Administration of live vaccines within four weeks of the first dose of mosunetuzumab or anticipation that live vaccine will be required during the study.
16. History of severe allergic or anaphylactic reactions to chimeric, human, or humanized antibodies, or fusion proteins.
17. Known or suspected hemophagocytic syndrome.
18. Prior allogeneic hematopoietic stem cell transplant.
19. Other current severe medical problems or expected survival of less than approximately five years for non-lymphoma reasons.
20. Current or previous other malignancy within three years of study entry, except cured basal or squamous cell skin cancer, superficial bladder cancer, prostate intraepithelial neoplasm, carcinoma in situ of the cervix, or other non-invasive or indolent malignancy without sponsor approval.
21. Psychiatric disorder or dementia which make the patient unable to give an informed consent and/or adhere to the schedule.
22. Pregnancy or breast-feeding.
23. HIV positivity: Subjects that are on HIV-treatment with undetectable HIV-RNA and CD4-counts above 200 will be eligible.
24. Women of reproductive potential not agreeing to use an acceptable method of birth control during treatment and for three months after completion of treatment.

Where this trial is running

Helsinki and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Lymphoma, Follicular
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.