Last reviewed 2026-04-20 · How we verify

INOTUZUMAB OZOGAMICIN

Inotuzumab ozogamicin is a CD22-directed antibody-drug conjugate that binds to CD22 on tumor cells, internalizes, and releases a cytotoxic agent causing DNA damage and cell death.

Inotuzumab ozogamicin is a marketed CD22-directed antibody-drug conjugate for relapsed or refractory CD22+ B-cell precursor ALL. Its key strength lies in its mechanism of action, which targets CD22 on tumor cells and releases a cytotoxic agent to cause DNA damage and cell death. The primary risk is the key composition patent expiry in 2028, which could lead to increased competition.

At a glance

Mechanism of action

The ADC binds to CD22 on the surface of B-cell precursor ALL cells, leading to internalization and release of the cytotoxic agent N-acetyl-gamma-calicheamicin, which causes double-strand DNA breaks, cell cycle arrest, and apoptosis.

Approved indications

• Relapsed or Refractory CD22+ B-cell Precursor ALL

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

• Thrombocytopenia
• Pyrexia
• Neutropenia
• Infection
• Anemia
• Vomiting
• Leukopenia
• Hemorrhage
• Fatigue
• Nausea
• Febrile neutropenia
• Headache

Drug interactions

• Drugs that prolong the QT interval or induce Torsades de Pointes may increase the risk of a clinically significant QTc interval prolongation when used concomitantly with BESPONSA.

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:

• INOTUZUMAB OZOGAMICIN CI brief — competitive landscape report
• INOTUZUMAB OZOGAMICIN updates RSS · CI watch RSS