Last reviewed 2026-04-20 · How we verify

Besponsa (inotuzumab)

Besponsa (generic name: inotuzumab) is a CD22-directed Immunoconjugate [EPC] Monoclonal antibody drug developed by Pfizer. It is currently FDA-approved (first approved 2017) for Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in adult patients, Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in pediatric patients 1 year and older.

Inotuzumab ozogamicin is a CD22-directed antibody drug conjugate that targets and kills cancer cells.

Inotuzumab ozogamicin, sold under the brand name Besponsa, is an antibody-drug conjugate medication used to treat relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL). It is administered by intravenous infusion. Pfizer Inc. developed this drug. The mechanism of action involves binding to CD22-expressing tumor cells, followed by internalization and release of a cytotoxic agent. This results in cell cycle arrest and apoptotic cell death. The commercial significance of this drug is its ability to generate $1.4 billion in revenue. It has been approved for use in adult and pediatric patients with relapsed or refractory CD22-positive B-cell precursor ALL.

At a glance

Mechanism of action

Inotuzumab ozogamicin works by binding to the CD22 protein on the surface of cancer cells. This binding causes the cancer cells to internalize the drug, which then releases a cytotoxic agent that kills the cells. This mechanism of action is specific to cancer cells that express the CD22 protein, making it a targeted therapy.

Approved indications

• Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in adult patients
• Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in pediatric patients 1 year and older

Boxed warnings

• WARNING: HEPATOTOXICITY, INCLUDING HEPATIC VENO-OCCLUSIVE DISEASE (VOD) (ALSO KNOWN AS SINUSOIDAL OBSTRUCTION SYNDROME) and INCREASED RISK OF POST-HEMATOPOIETIC STEM CELL TRANSPLANT (HSCT) NON-RELAPSE MORTALITY WARNING: HEPATOTOXICITY, INCLUDING HEPATIC VENO-OCCLUSIVE DISEASE (VOD) (ALSO KNOWN AS SINUSOIDAL OBSTRUCTION SYNDROME) and INCREASED RISK OF POST- HEMATOPOIETIC STEM CELL TRANSPLANT (HSCT) NON-RELAPSE MORTALITY See full prescribing information for complete boxed warning. • Hepatotoxicity, including fatal and life-threatening VOD occurred in patients who received BESPONSA. ( 5.1 ) • A higher post-HSCT non-relapse mortality rate occurred in patients receiving BESPONSA ( 5.2 ) HEPATOTOXICITY, INCLUDING VOD • Hepatotoxicity, including fatal and life-threatening VOD occurred in patients with relapsed or refractory acute lymphoblastic leukemia (ALL) who received BESPONSA. The risk of VOD was greater in patients who underwent HSCT after BESPONSA treatment; use of HSCT conditioning regimens containing 2 alkylating agents and last total bilirubin level ≥ upper limit of normal (ULN) before HSCT were significantly associated with an increased risk of VOD. • Other risk factors for VOD in patients treated with BESPONSA included ongoing or prior liver disease, prior HSCT, increased age, later salvage lines, and a greater number of BESPONSA treatment cycles. • Elevation of liver tests may require dosing interruption, dose reduction, or permanent discontinuation of BESPONSA. Permanently discontinue treatment if VOD occurs. If severe VOD occurs, treat according to standard medical practice [see Dosage and Administration (2.3) and Warnings and Precautions (5.1) ]. INCREASED RISK OF POST-HSCT NON-RELAPSE MORTALITY • There was higher post-HSCT non-relapse mortality rate in patients receiving BESPONSA, resulting in a higher Day 100 post-HSCT mortality rate [see Warnings and Precautions (5.2) ] .

Common side effects

• Infection
• Thrombocytopenia
• Neutropenia
• Anemia
• Leukopenia
• Febrile neutropenia
• Lymphopenia
• Decreased appetite
• Headache
• Hemorrhage
• Nausea
• Abdominal pain

Drug interactions

• BESPONSA
• drugs known to prolong the QT interval
• drugs that do not prolong QT/QTc
• drugs known to prolong QT/QTc

Key clinical trials

• Pediatric-Inspired Regimen Combined With Venetoclax and Immunotherapy for Adult Ph-Negative Acute Lymphoblastic Leukemia (NA)
• A Treatment Study Protocol for Participants 0-45 Years With Acute Lymphoblastic Leukaemia (PHASE3)
• Testing the Use of Steroids and Tyrosine Kinase Inhibitors With Blinatumomab or Chemotherapy for Newly Diagnosed BCR-ABL-Positive Acute Lymphoblastic Leukemia in Adults (PHASE3)
• Inotuzumab Ozogamicin and Blinatumomab With or Without Ponatinib in Treating Patients With Newly Diagnosed, Recurrent, or Refractory CD22-Positive B-Lineage Acute Lymphoblastic Leukemia (PHASE2)
• Immunotherapy Combined With Auto-HSCT and CD22/CD19 CAR-T Sandwich Strategy for B-ALL (PHASE2)
• Full-Course Immunotherapy Consolidation for Unfit or Fit B-ALL Who Decline Chemotherapy (PHASE2)
• A Study to Learn More About the Study Medicine Called Inotuzumab Ozogamicin (InO) in Children (1 to <18 Years) With First Relapse ALL (PHASE2)
• Treatment of Patients With Diffuse Large B Cell Lymphoma Who Are Not Suitable for Anthracycline Containing Chemotherapy (PHASE2)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Besponsa CI brief — competitive landscape report
• Besponsa updates RSS · CI watch RSS
• Pfizer portfolio CI

Frequently asked questions about Besponsa

Related

• Drug class: All CD22-directed Immunoconjugate [EPC] drugs
• Target: All drugs targeting CD22
• Manufacturer: Pfizer — full pipeline
• Therapeutic area: All drugs in Oncology
• Indication: Drugs for Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in adult patients
• Indication: Drugs for Relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia (ALL) in pediatric patients 1 year and older

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing