Besponsa (inotuzumab ozogamicin)
Pfizer · CD22-Targeted Antibody-Drug Conjugate (ADC)
What is Besponsa? Besponsa (inotuzumab ozogamicin) is a CD22-targeted antibody-drug conjugate by Pfizer approved for adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL). It delivers calicheamicin (a DNA-damaging agent) directly to CD22-expressing leukemia cells.
About Besponsa
| Brand Name | Besponsa |
| Generic / INN | inotuzumab ozogamicin |
| Drug Class | CD22-Targeted Antibody-Drug Conjugate (ADC) |
| Manufacturer | Pfizer |
| Administration | Intravenous (IV) infusion |
| FDA Approval | 2017 |
FDA-Approved Uses
- Relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL) — adults
How Does Besponsa Work?
Inotuzumab ozogamicin consists of an anti-CD22 antibody linked to calicheamicin (a potent enediyne antibiotic). After binding CD22 on B-cell ALL cells and internalization, calicheamicin is released and causes double-strand DNA breaks leading to apoptosis. CD22 is expressed in over 90% of B-cell ALL.
Dosage & Administration
Cycle 1: 0.8 mg/m² day 1, then 0.5 mg/m² days 8 and 15 of a 21-day cycle. Subsequent cycles: 0.5 mg/m² on days 1, 8, and 15. Maximum 6 cycles. Premedicate before each dose (corticosteroid, antipyretic, antihistamine).
Dosing is individualized by the treating oncologist. Do not adjust without medical guidance. This page is educational only.
Warnings & Side Effects
- Hepatotoxicity/VOD/SOS — BOXED WARNING, can be fatal post-HSCT
- Increased post-HSCT non-relapse mortality
- Myelosuppression
- QTc prolongation
- Embryo-fetal toxicity
Common Side Effects
- Thrombocytopenia
- Neutropenia
- Anemia
- Fatigue
- Nausea
- Fever
- Infection
- Elevated liver enzymes
- QTc prolongation
Storage & Handling
Refrigerate at 2°C to 8°C (36°F to 46°F). Protect from light. Diluted solution stable 4 hours at room temperature.
💰 Medication Cost & Insurance Coverage
Approximate Wholesale Acquisition Cost (WAC / List Price)
~$20,000–$25,000/cycle
CD22 ADC for ALL
Insurance & Prior Authorization
Besponsa requires prior authorization from all major insurance plans. BiologicHealthPlus handles the full PA process — clinical documentation, peer-to-peer reviews, and appeals — at no cost to patients or providers.
Prior Authorization Guide Patient Assistance Insurance & Savings
Frequently Asked Questions — Besponsa
Besponsa is a CD22-targeted ADC by Pfizer for relapsed/refractory B-cell ALL. It delivers calicheamicin — a highly potent DNA-damaging agent — directly into CD22-positive leukemia cells.
Veno-occlusive disease (VOD), also called sinusoidal obstruction syndrome (SOS), is a potentially fatal liver complication. The risk is highest in patients who subsequently undergo stem cell transplant. Liver function must be monitored closely.
Besponsa is covered by Medicare Part B and commercial insurance for relapsed/refractory B-cell ALL with prior authorization.
Related Medications & Conditions
Related Medications
Blinatumomab (Blincyto — CD3×CD19 BiTE) · Kymriah (tisagenlecleucel — CD19 CAR-T) · Asparaginase · Vincristine
Related Conditions
Acute lymphoblastic leukemia (ALL) · B-cell precursor ALL · Relapsed/refractory ALL