Last reviewed 2026-04-19 · How we verify

Nipent (Pentostatin)

Nipent (pentostatin) is a nucleoside analog marketed by Pfizer for treating hairy cell leukemia, including alpha-interferon-refractory cases. It functions as a potent inhibitor of adenosine deaminase, leading to accumulation of toxic metabolites in lymphoid cells. The drug is indicated for patients with active disease presenting with clinically significant cytopenias or disease-related symptoms. As a single-agent therapy, it has demonstrated efficacy in both treatment-naive and previously treated populations. Nipent represents an established therapeutic option in the hematologic malignancy landscape with a well-characterized safety and efficacy profile.

At a glance

Approved indications

• Untreated hairy cell leukemia with active disease
• Alpha-interferon-refractory hairy cell leukemia with active disease
• Hairy cell leukemia patients with clinically significant anemia
• Hairy cell leukemia patients with neutropenia
• Hairy cell leukemia patients with thrombocytopenia
• Hairy cell leukemia patients with disease-related symptoms

Boxed warnings

• WARNING NIPENT should be administered under the supervision of a physician qualified and experienced in the use of cancer chemotherapeutic agents. The use of higher doses than those specified (see DOSAGE AND ADMINISTRATION ) is not recommended. Dose-limiting severe renal, liver, pulmonary, and CNS toxicities occurred in Phase 1 studies that used NIPENT at higher doses (20-50 mg/m 2 in divided doses over 5 days) than recommended. In a clinical investigation in patients with refractory chronic lymphocytic leukemia using NIPENT at the recommended dose in combination with fludarabine phosphate, 4 of 6 patients entered in the study had severe or fatal pulmonary toxicity. The use of NIPENT in combination with fludarabine phosphate is not recommended.

Common side effects

• Nausea and/or Vomiting
• Fever
• Rash
• Fatigue
• Leukopenia
• Pruritus
• Coughing/Increased Cough
• Myalgia
• Chills
• Headache
• Diarrhea
• Abdominal Pain

Drug interactions

• Allopurinol
• Vidarabine
• Fludarabine phosphate
• Carmustine
• Etoposide
• Cyclophosphamide (high dose)

Key clinical trials

• Pilot Trial of Allogeneic Blood or Marrow Transplantation for Primary Immunodeficiencies (PHASE2)
• A Study to Evaluate Axatilimab Versus Best Available Therapy in Participants With Chronic Graft Versus Host Disease After at Least 2 Prior Lines of Systemic Therapy (PHASE3)
• Allogeneic Hematopoietic Cell Transplantation for Disorders of T-cell Proliferation and/or Dysregulation (PHASE2)
• A Blood Stem Cell Transplant for Sickle Cell Disease (PHASE1)
• Trial of Allogeneic Reduced-Intensity, HLA-Haploidentical Allogeneic Hematopoietic Cell Bone Marrow Transplantation Followed by Graft-versus-Host-Disease (GVHD) Prophylaxis With Cyclophosphamide, Bortezomib and Maraviroc for Hematologic Malignancies ... (PHASE1, PHASE2)
• A Reduced-Intensity Conditioning Regimen (Cyclophosphamide, Pentostatin, Anti-thymocyte Globulin) Followed by Haploidentical Hematopoietic Stem Cell Transplant for the Treatment of Patients With Refractory or Recurrent Severe Aplastic Anemia (PHASE1)
• Allogeneic Hematopoietic Cell Transplantation for Peripheral T Cell Lymphoma (PHASE2)
• A Study of Ruxolitinib vs Best Available Therapy (BAT) in Patients With Steroid-refractory Chronic Graft vs. Host Disease (GvHD) After Bone Marrow Transplantation (REACH3) (PHASE3)

Primary sources

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