Tafasitamab, Retifanlimab, and Rituximab in Combination With Standard Therapy for the Treatment of Diffuse Large B-cell Lymphoma

OUTLINE: PREPHASE THERAPY: Patients receive tafasitamab intravenously (IV) over 30 minutes on days 1, 8, and 15 of each cycle, rituximab and hyaluronidase human subcutaneously (SC) on day 1 of each cycle, and retifanlimab IV over 30 minutes on day 8 of each cycle. Treatment repeats every 21 days for 2 cycles in the absence of disease progression or unacceptable toxicity. COMBINATION THERAPY: After completion of prephase therapy or if patients progress during prephase therapy, patients receive tafasitamab IV over 30 minutes, retifanlimab IV over 30 minutes, rituximab and hyaluronidase human SC, cyclophosphamide IV, doxorubicin IV, and vincristine IV on day 1 of each cycle. Patients with an international prognostic index (IPI) score of 2-5 may receive polatuzumab vedotin IV in place of vincristine at investigator discretion. Patients also receive prednisone orally (PO) on days 1-5 of each cycle. Treatment repeats every 21 days for 4-6 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo optional bone marrow biopsy and aspiration and multi-gated acquisition (MUGA) scan at screening, and fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scan and collection of blood and tissue samples throughout the trial. After completion of study treatment, patients are followed up at 4-6 weeks, 12 weeks and then per routine care for up to 5 years.