Anti-CD22 antibody-drug conjugate Pregnancy: Can cause embryo-fetal harm based on mechanism of action and animal studies (embryo-fetal toxicity in rats at maternal exposures >=0.4 times the exposure at the maximum recommended dose). No data in pregnant women. Advise patients of the potential risk to a fetus and to use effective contraception.

Inotuzumab ozogamicin (Specialist drug)

Brand names: Besponsa

Inotuzumab ozogamicin is an anti-CD22 antibody-drug conjugate used as a specialist treatment for relapsed or refractory CD22-positive B-cell acute lymphoblastic leukaemia. It is given by intravenous infusion under haemato-oncology supervision.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Cycle 1: total 1.8 mg/m2 per cycle, given as 3 divided doses - Day 1: 0.8 mg/m2, Day 8: 0.5 mg/m2, Day 15: 0.5 mg/m2

Route: Intravenous infusion only (reconstituted lyophilised powder, further diluted)

Frequency: Cycle 1 is 21 days (may be extended to 28 days if the patient achieves CR or CRi and/or to allow recovery from toxicity). Subsequent cycles are 28 days: patients who achieved CR or CRi receive 1.5 mg/m2 per cycle (0.5 mg/m2 on Days 1, 8 and 15); patients who have not achieved CR or CRi receive 1.8 mg/m2 per cycle (0.8 mg/m2 Day 1, 0.5 mg/m2 Days 8 and 15). Day 8 may vary +/- 2 days, maintaining a minimum of 6 days between doses.

Max: Maximum of 6 cycles for patients not proceeding to HSCT; for patients proceeding to HSCT the recommended duration is 2 cycles (a third cycle may be considered if CR/CRi and MRD negativity are not achieved after 2 cycles)

Source: US FDA prescribing information for BESPONSA (Wyeth Pharmaceuticals LLC / Pfizer, label date 2026-02-06, https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=427d10d2-c29d-4b71-a5fe-c97736d59aa6). NO UK eMC SPC WAS IN THE SOURCE BUNDLE - dose is taken from US labelling and must be verified against the UK SPC before publication. VERBATIM: 'For the first cycle, the recommended total dose of BESPONSA for all patients is 1.8 mg/m2 per cycle, administered as 3 divided doses on Day 1 (0.8 mg/m2), Day 8 (0.5 mg/m2), and Day 15 (0.5 mg/m2).' Dose is based on the patient's body surface area (m2). Patients who do not achieve a CR or CRi within 3 cycles should discontinue treatment. PRE-MEDICATION: a corticosteroid, an antipyretic and an antihistamine before every dose; observe the patient during and for at least 1 hour after the end of the infusion for infusion-related reactions. CYTOREDUCTION: for patients with circulating lymphoblasts, cytoreduce with hydroxyurea, steroids and/or vincristine to a peripheral blast count <=10,000/mm3 before the first dose. DOSE MODIFICATION: doses within a cycle (Days 8 and/or 15) do not need to be interrupted for neutropenia or thrombocytopenia, but interruption within a cycle is recommended for non-haematological toxicities; if the dose is reduced for toxicity it must not be re-escalated. If pre-treatment ANC was >=1 x 10^9/L and ANC falls, interrupt the next cycle until ANC recovers to >=1 x 10^9/L (discontinue if low ANC persists >28 days and is suspected to be drug-related); if pre-treatment platelets were >=50 x 10^9/L and platelets fall, interrupt the next cycle until platelets recover to >=50 x 10^9/L. GERIATRIC: no starting-dose adjustment based on age. PAEDIATRIC: safety and effectiveness established in patients 1 year and older with relapsed or refractory CD22-positive B-cell precursor ALL (dose is by body surface area, NOT per kg, so paedDose is null); higher incidence of liver test abnormalities than in adults (grade 3-4 AST/ALT/bilirubin rises in 21%/21%/9% vs 4%/4%/5%); not established below 1 year of age. Verify any under-18 use against a children's formulary and local protocol. NOTE: source label sections were truncated at the fetch limit - the full dose-modification tables were not retrieved.

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

None (US label section 4 states 'None')

Side effects

Thrombocytopenia, neutropenia, leukopenia and anaemia (myelosuppression)
Hepatotoxicity including hepatic veno-occlusive disease / sinusoidal obstruction syndrome (occurred in 14% of adults in INO-VATE ALL, sometimes fatal); transaminases, GGT and bilirubin increased
Infection, febrile neutropenia and pyrexia
Nausea, vomiting and abdominal pain
Infusion-related reactions; QT interval prolongation
Haemorrhage, fatigue and headache

Interactions

Drugs that prolong the QT interval or induce Torsades de Pointes - concomitant use may increase the risk of clinically significant QTc prolongation; discontinue or substitute alternative agents that do not prolong QT/QTc. Where concomitant use is unavoidable, obtain ECGs and electrolytes before starting, after initiation of the QT-prolonging drug, and periodically during treatment

Clinical monograph

How it works

The antibody targets CD22 on B-lineage leukaemic cells and delivers the cytotoxic agent calicheamicin intracellularly, causing DNA double-strand breaks and cell death.

Prescribing in practice

Hepatotoxicity, including potentially fatal veno-occlusive disease (sinusoidal obstruction syndrome), is a major risk, particularly around haematopoietic stem cell transplant.
Premedication and tumour lysis precautions are used, and infusion reactions can occur.
Prolongation of the QT interval and myelosuppression require attention and supportive management.

Monitoring

Monitor liver function tests closely, full blood count, and for signs of veno-occlusive disease and infection throughout treatment.

Counselling the patient

Report yellowing of the skin or eyes, abdominal swelling or right-sided abdominal pain promptly.
Report fever, bruising or bleeding, as blood counts can fall.
Effective contraception is required during and after treatment as advised by the team.

Evidence & guidelines

The INO-VATE ALL trial showed higher remission rates with inotuzumab ozogamicin than standard chemotherapy in relapsed or refractory B-cell ALL.

Reference: NICE TA541; SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways