This FDA approval affects oncologists, hematologists, and advanced practice clinicians treating adult patients with relapsed or refractory follicular lymphoma after prior systemic therapy; the approved regimen is tafasitamab‑cxix in combination with lenalidomide and rituximab as per the inMIND regimen evaluated in the randomized trial ^[2][3][1]. The inMIND data support adding tafasitamab‑cxix to lenalidomide and rituximab to improve investigator‑assessed progression‑free survival and overall response rate compared with lenalidomide and rituximab alone ^[3]. How tafasitamab‑cxix will be positioned relative to other approved FL regimens and how clinicians will monitor and manage the increased cytopenias and infection risks observed in inMIND remain questions for implementation in routine practice: what are the optimal prophylaxis and monitoring strategies in real‑world patients?

Q1 What is tafasitamab‑cxix (Monjuvi) approved for?

MONJUVI (tafasitamab‑cxix) is approved in combination with lenalidomide and rituximab for the treatment of adult patients with relapsed or refractory follicular lymphoma (FL). The approval was granted by the FDA on June 18, 2025, and the indication is based on the randomized inMIND trial showing improved investigator‑assessed progression‑free survival when tafasitamab‑cxix was added to lenalidomide and rituximab compared with placebo plus lenalidomide and rituximab. MONJUVI is also indicated in combination with lenalidomide for relapsed or refractory diffuse large B‑cell lymphoma under prior labeling.

Q2 How does tafasitamab‑cxix work?

Tafasitamab‑cxix is an Fc‑modified monoclonal antibody that binds the CD19 antigen on pre‑B and mature B lymphocytes and on several B‑cell malignancies. Upon CD19 binding, tafasitamab‑cxix mediates B‑cell lysis through apoptosis and immune effector mechanisms, including antibody‑dependent cellular cytotoxicity (ADCC) and antibody‑dependent cellular phagocytosis (ADCP). In vitro studies in DLBCL tumor cells showed increased ADCC activity when tafasitamab‑cxix was combined with lenalidomide.

Q3 What is the recommended dose of tafasitamab‑cxix for follicular lymphoma?

The recommended MONJUVI dose is 12 mg/kg administered as an intravenous infusion. For relapsed or refractory follicular lymphoma the approved regimen is MONJUVI plus lenalidomide and rituximab with MONJUVI dosing on Days 1, 8, 15, and 22 of Cycles 1‑3 and on Days 1 and 15 of Cycles 4‑12; lenalidomide 20 mg orally once daily on Days 1‑21 of Cycles 1‑12; and rituximab 375 mg/m2 intravenously on Days 1, 8, 15, and 22 of Cycle 1 and on Day 1 of Cycles 2‑5. After 12 cycles, continue MONJUVI as monotherapy until disease progression or unacceptable toxicity as described in the prescribing information. Clinicians should consult current prescribing information for complete dosing guidance.

Q4 What are the side effects clinicians should expect?

In patients with relapsed or refractory follicular lymphoma treated in inMIND, common adverse reactions (≥20%) included respiratory tract infections, diarrhea, rash, fatigue, constipation, musculoskeletal pain, and cough. Clinically significant laboratory abnormalities included decreases in neutrophils and lymphocytes; new or worsening Grade 3 or 4 cytopenias included decreased neutrophils in 48% (Grade 4, 19%) and decreased lymphocytes in 22% (Grade 4, 1.8%). Febrile neutropenia occurred in 4.4%. Grade 3 or higher infections occurred in 24% of patients with FL, including fatal infections in 1.1%; opportunistic infections occurred in 6% (herpes simplex or zoster 5%, fungal pneumonia 1.1%, Pneumocystis jirovecii pneumonia 0.4%, CMV reactivation 0.4%). Infusion‑related reactions occurred in 16% of patients with FL.

Clinicians should consult current prescribing information for complete dosing guidance.