Azacitidine
Brand names: Vidaza, Onureg (oral formulation)
Azacitidine is a hypomethylating cytotoxic agent used for higher-risk myelodysplastic syndromes, chronic myelomonocytic leukaemia and acute myeloid leukaemia in patients not suitable for stem cell transplantation.
Adult dose
Dose adjustments
Azacitidine can be administered to patients with renal impairment without initial dose adjustment. If unexplained reductions in serum bicarbonate levels to less than 20 mmol/L occur, the dose should be reduced by 50% on the next cycle. If unexplained elevations in serum creatinine or blood urea nitrogen to 2-fold or more above baseline values and above the upper limit of normal occur, the next cycle should be delayed until values return to normal or baseline and the dose should be reduced by 50% on the next treatment cycle.
Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.
Contraindications
- Hypersensitivity to the active substance or to any of the excipients
- Advanced malignant hepatic tumours
- Breast-feeding
Side effects
- Haematological reactions (71.4% of patients) including thrombocytopenia, neutropenia and leukopenia, usually Grade 3-4
- Febrile neutropenia (8.0% as a serious adverse reaction in MDS/CMML/AML; 25.0% in patients aged 65 or over with AML and more than 30% marrow blasts)
- Gastrointestinal events (60.6%) including nausea and vomiting, usually Grade 1-2; also constipation (41.9%) and diarrhoea (36.9%) in the older AML population
- Injection site reactions (77.1%), usually Grade 1-2
- Anaemia; infections including pneumonia and neutropenic sepsis, some with fatal outcome
- Haemorrhagic events including cerebral haemorrhage (0.5%), gastrointestinal haemorrhage (0.8%) and intracranial haemorrhage (0.5%); hypersensitivity reactions (0.25%)
Clinical monograph
How it works
As a pyrimidine nucleoside analogue it is incorporated into nucleic acids and inhibits DNA methyltransferase, causing DNA hypomethylation and direct cytotoxicity to abnormal haematopoietic cells.
Prescribing in practice
- It causes marked myelosuppression, so monitor blood counts and manage neutropenia, anaemia and thrombocytopenia and associated infection and bleeding risk.
- It is given in repeated treatment cycles, typically as a subcutaneous injection, with antiemetic cover.
- Hepatic and renal impairment require caution, and it can cause serious tumour lysis and injection-site reactions.
Monitoring
Monitor full blood count before and during each cycle, along with renal and hepatic function.
Counselling the patient
- Report fever, sore throat, bruising or bleeding, which may indicate low blood counts.
- Treatment is given in cycles and several cycles may be needed before benefit is seen.
- Effective contraception is required during treatment.
Evidence & guidelines
The landmark AZA-001 trial showed azacitidine improved overall survival compared with conventional care in higher-risk myelodysplastic syndromes.
Reference: AZA-001 Trial (Fenaux et al. Lancet Oncology 2009); NICE TA218; NICE TA666 (oral azacitidine); 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).
Related
Curated clinical cross-links plus same-class fallbacks.
- Major Haemorrhage / Massive Transfusion · BCSH; RCOA; RCEM; RCS — BCSH Guidelines
- Anaemia Investigation · BSH / NICE
- Splenomegaly Workup · BSH; BMJ Best Practice
- Deep Vein Thrombosis Diagnosis and Treatment · NICE CG144 / NICE NG158
- Sickle Cell Crisis · BSH 2021 / BCSH
- Neutropenic Sepsis · NICE CG151 2012 / ESMO