Azacitidine Tillomed: Uses, Dosage & Side Effects
A hypomethylating agent used to treat myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML), and acute myeloid leukaemia (AML) in adults who are not eligible for haematopoietic stem cell transplantation or intensive chemotherapy
Azacitidine Tillomed is a hypomethylating agent containing azacitidine, a pyrimidine nucleoside analogue used in the treatment of myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML), and acute myeloid leukaemia (AML). It works by restoring normal function to genes that control cell growth and differentiation, which are often silenced by abnormal DNA methylation in these blood cancers. Azacitidine Tillomed is given as a subcutaneous injection in a hospital or clinic setting and requires a prescription. It is a generic equivalent of the originator product Vidaza and has been shown in landmark clinical trials to improve overall survival in higher-risk MDS patients compared to conventional care.
Quick Facts: Azacitidine Tillomed
Key Takeaways
- Azacitidine Tillomed is a hypomethylating agent approved for higher-risk MDS, CMML with 10–29% blasts, and AML with 20–30% blasts and multi-lineage dysplasia in adults not eligible for transplant.
- Treatment is given as subcutaneous injections for 7 days in each 28-day cycle; a minimum of 6 cycles is recommended before assessing response.
- The most common side effects are blood count reductions (neutropenia, thrombocytopenia, anaemia), injection site reactions, nausea, and fatigue.
- Regular blood count monitoring is essential throughout treatment to manage myelosuppression and prevent serious infections or bleeding.
- Azacitidine Tillomed is a generic equivalent of Vidaza and meets the same EMA quality, safety, and efficacy standards as the originator product.
What Is Azacitidine Tillomed and What Is It Used For?
Azacitidine Tillomed contains the active substance azacitidine, which belongs to a class of medicines known as hypomethylating agents or antimetabolites. It is classified under ATC code L01BC07 and is primarily used in the treatment of myeloid malignancies—cancers affecting the blood and bone marrow. Azacitidine was first approved by the FDA in 2004 and subsequently by the EMA in 2009, representing a significant advance in the treatment of higher-risk myelodysplastic syndromes.
Myelodysplastic syndromes are a group of blood cancers in which the bone marrow fails to produce enough healthy blood cells. Immature blood cells (blasts) accumulate in the bone marrow and blood, leading to low blood counts (cytopenias) and a risk of progression to acute myeloid leukaemia. Before the approval of azacitidine, treatment options for patients with higher-risk MDS who were not candidates for intensive chemotherapy or stem cell transplantation were extremely limited.
Azacitidine Tillomed is specifically indicated for the treatment of adult patients with the following conditions who are not eligible for haematopoietic stem cell transplantation (HSCT):
- Intermediate-2 and high-risk myelodysplastic syndromes (MDS) according to the International Prognostic Scoring System (IPSS), including refractory anaemia with excess blasts (RAEB-1 and RAEB-2)
- Chronic myelomonocytic leukaemia (CMML) with 10–29% marrow blasts without myeloproliferative disorder
- Acute myeloid leukaemia (AML) with 20–30% blasts and multi-lineage dysplasia, according to WHO classification
- AML with more than 30% marrow blasts in adult patients aged 65 years and older who are not eligible for intensive induction chemotherapy
The landmark AZA-001 trial, published in The Lancet Oncology in 2009, demonstrated that azacitidine significantly improved overall survival in patients with higher-risk MDS compared to conventional care regimens. The median overall survival was 24.5 months with azacitidine versus 15.0 months with conventional care, establishing azacitidine as the standard of care for this patient population. This survival benefit has been consistently supported by subsequent real-world evidence and observational studies.
How Does Azacitidine Work?
Azacitidine is a pyrimidine nucleoside analogue of cytidine, one of the building blocks of DNA and RNA. It exerts its therapeutic effects through two principal mechanisms that work at different concentration levels:
DNA hypomethylation (at lower concentrations): Azacitidine becomes incorporated into DNA during cell replication, where it inhibits the enzyme DNA methyltransferase (DNMT). This enzyme is responsible for adding methyl groups to DNA, a process called methylation. In MDS and AML, abnormal hypermethylation of tumour suppressor gene promoters silences these genes, allowing uncontrolled cell growth. By blocking DNMT, azacitidine reverses this aberrant methylation, reactivating tumour suppressor genes and restoring normal cell differentiation and growth control.
Direct cytotoxicity (at higher concentrations): At higher doses, azacitidine is incorporated into both RNA and DNA of rapidly dividing abnormal cells. This incorporation disrupts nucleic acid metabolism and protein synthesis, leading to cell death. This dual mechanism makes azacitidine effective against the abnormal blast cells that characterise MDS and AML.
Unlike intensive chemotherapy, which aims to destroy all rapidly dividing cells, azacitidine works more selectively by targeting the epigenetic abnormalities that drive these diseases. This is why azacitidine treatment is generally better tolerated than conventional induction chemotherapy and can be administered in an outpatient setting, making it a viable option for older patients and those with significant comorbidities.
What Should You Know Before Taking Azacitidine Tillomed?
Contraindications
Azacitidine Tillomed must not be used in the following circumstances:
- Hypersensitivity to azacitidine or to mannitol (an excipient in the formulation)
- Advanced malignant hepatic tumours: Patients with liver cancer that has spread extensively should not receive azacitidine due to the risk of severe hepatotoxicity
- Pregnancy: Azacitidine is teratogenic (causes birth defects) based on animal studies and must not be used during pregnancy
- Breastfeeding: It is not known whether azacitidine or its metabolites are excreted in breast milk; breastfeeding must be discontinued during treatment
Azacitidine causes severe myelosuppression (reduction in blood cell production). Complete blood counts must be performed before each treatment cycle. Treatment may need to be delayed or doses reduced if blood counts are dangerously low. Patients are at increased risk of serious infections and bleeding during treatment.
Warnings and Precautions
Before and during treatment with Azacitidine Tillomed, your doctor will take several precautions to ensure your safety. The following warnings and precautions are particularly important:
Haematological toxicity: Azacitidine commonly causes neutropenia (low white blood cells), thrombocytopenia (low platelets), and anaemia. These effects are expected and are part of the drug's mechanism of action against abnormal bone marrow cells. However, severe cytopenias increase the risk of life-threatening infections and bleeding. Complete blood counts should be performed before each treatment cycle, and dose adjustments or treatment delays may be necessary. Patients should be instructed to report signs of infection (fever, chills, persistent cough) or bleeding (unusual bruising, blood in urine or stool, nosebleeds) immediately.
Hepatotoxicity: Cases of hepatic failure, including fatal hepatic coma, have been reported in patients receiving azacitidine, particularly those with pre-existing liver disease or extensive tumour burden with liver metastases. Liver function tests should be monitored before each cycle. Azacitidine is contraindicated in patients with advanced malignant hepatic tumours.
Renal toxicity: Renal abnormalities including elevated serum creatinine, renal tubular acidosis, and renal failure have been reported. Patients with pre-existing renal impairment should be closely monitored. Serum creatinine and electrolytes should be checked before initiation of treatment and before each cycle. If unexplained reductions in serum bicarbonate occur (below 20 mmol/L), the dose should be reduced by 50% on the next cycle.
Tumour lysis syndrome: Patients with high tumour burden prior to treatment may be at risk of tumour lysis syndrome, a condition where the rapid breakdown of cancer cells releases their contents into the bloodstream. Appropriate precautions, including hydration and monitoring of uric acid levels, should be taken.
Cardiac events: Patients with pre-existing cardiac disease or a history of congestive heart failure should be monitored carefully, as cardiac events including cardiac failure have been reported during azacitidine treatment.
Pregnancy and Breastfeeding
Azacitidine Tillomed is strictly contraindicated during pregnancy. In preclinical studies, azacitidine caused significant developmental toxicity in rats and mice, including skeletal abnormalities, reduced fetal weight, and embryo-fetal death. There are no adequate and well-controlled studies in pregnant women, but based on its mechanism of action and the animal data, azacitidine is expected to cause fetal harm.
Women of childbearing potential must use highly effective contraception during treatment with azacitidine and for 6 months after the last dose. A pregnancy test should be performed before starting treatment. If a woman becomes pregnant during treatment, she must be informed of the potential hazard to the fetus.
Male patients with female partners of childbearing potential should use effective contraception during treatment and for 3 months after the last dose. Male fertility may be affected by azacitidine treatment; men should be counselled about sperm preservation options before starting therapy.
Breastfeeding must be discontinued during treatment with azacitidine, as it is unknown whether the drug is excreted in human breast milk. Given the potential for serious adverse reactions in breastfed infants, nursing must be stopped during the entire treatment period.
How Does Azacitidine Tillomed Interact with Other Drugs?
Azacitidine undergoes spontaneous hydrolysis and deamination by the enzyme cytidine deaminase. It does not appear to be significantly metabolised by cytochrome P450 (CYP) isoenzymes, which means classical drug-drug interactions via CYP enzyme inhibition or induction are unlikely. However, there are several clinically important pharmacodynamic interactions that must be considered:
Major Interactions
| Interacting Drug/Class | Effect | Recommendation |
|---|---|---|
| Live vaccines (e.g., MMR, varicella, yellow fever) | Risk of disseminated vaccine infection due to immunosuppression | Avoid live vaccines during treatment and for a period after treatment ends; use inactivated vaccines where possible |
| Other myelosuppressive agents (e.g., chemotherapy, methotrexate) | Additive bone marrow suppression leading to severe cytopenias | Monitor blood counts more frequently; dose adjustments may be required |
| Nephrotoxic agents (e.g., aminoglycosides, ciclosporin, NSAIDs) | Increased risk of renal impairment; azacitidine can cause renal tubular acidosis | Monitor renal function closely; consider alternative agents where possible |
| Hepatotoxic agents (e.g., paracetamol in high doses, methotrexate) | Increased risk of liver damage; hepatic failure has been reported with azacitidine | Monitor liver function tests regularly; use with caution |
Minor Interactions
| Interacting Drug/Class | Effect | Recommendation |
|---|---|---|
| Anticoagulants (e.g., warfarin, heparin) | Increased bleeding risk due to thrombocytopenia from azacitidine | Monitor platelet counts and coagulation parameters closely |
| Antiplatelet agents (e.g., aspirin, clopidogrel) | Increased bleeding risk due to additive effect on platelet function | Review necessity; monitor for signs of bleeding |
| Anti-emetics (e.g., ondansetron) | No significant interaction; commonly co-prescribed for nausea management | Safe to use; pre-medication with anti-emetics is recommended |
Although formal pharmacokinetic interaction studies are limited, the lack of CYP450 metabolism suggests a low potential for classical drug interactions. The main concerns are pharmacodynamic in nature—primarily additive myelosuppression, immunosuppression, and organ toxicity. Always inform your healthcare team about all medicines you are taking, including over-the-counter drugs and herbal supplements.
What Is the Correct Dosage of Azacitidine Tillomed?
Azacitidine Tillomed should only be initiated and supervised by a physician experienced in the use of chemotherapeutic agents. Pre-medication with anti-emetics (e.g., ondansetron) is recommended for nausea and vomiting prevention. The dose is calculated based on the patient's body surface area (BSA), and the powder must be reconstituted with water for injections to form a 25 mg/ml suspension before administration.
Adults
Standard Dosing Regimen
The recommended starting dose for the first treatment cycle, for all patients regardless of baseline haematology laboratory values, is 75 mg/m² body surface area, injected subcutaneously, daily for 7 consecutive days, followed by a rest period of 21 days (28-day treatment cycle).
Pre-medication for nausea and vomiting is recommended. The subcutaneous injection should be given in the upper arm, thigh, or abdomen, with injection sites rotated between these areas. New injections should be given at least 2.5 cm from the previous site and never into areas that are tender, bruised, red, or hardened.
| Patient Group | Dose | Schedule | Notes |
|---|---|---|---|
| Adults (all indications) | 75 mg/m² SC | Days 1–7 of 28-day cycle | Minimum 6 cycles recommended |
| Renal impairment (mild to moderate) | 75 mg/m² SC | Days 1–7 of 28-day cycle | No dose adjustment; monitor renal function |
| Renal impairment (if serum bicarbonate <20 mmol/L) | 50% dose reduction | Days 1–7 of 28-day cycle | Reduce by 50% on next cycle |
| Hepatic impairment | 75 mg/m² SC | Days 1–7 of 28-day cycle | No specific adjustment; monitor LFTs closely |
| Elderly (≥65 years) | 75 mg/m² SC | Days 1–7 of 28-day cycle | No dose adjustment based on age alone |
Dose Adjustments for Haematological Toxicity
Treatment with azacitidine may need to be delayed or the dose adjusted based on blood count results. The following dose modification guidelines apply after the first cycle:
- If nadir counts (lowest blood counts) are ANC < 0.5 × 109/L or platelets < 25 × 109/L: reduce dose by 50% on the next cycle if the nadir was in the first or second cycle, unless clear improvement in differentiation is seen
- If blood counts have not recovered to ANC ≥ 1.0 × 109/L and platelets ≥ 50 × 109/L by Day 28: delay the next cycle and perform blood counts weekly until recovery, then reduce dose by 50% on the next cycle
- If recovery takes more than 14 days beyond Day 28 and no clear improvement in differentiation: consider discontinuing treatment
Children and Adolescents
The safety and efficacy of azacitidine in children and adolescents below 18 years of age have not been established. There are no data available, and azacitidine is not recommended for use in this age group.
Missed Dose
If a scheduled injection is missed, it should be given as soon as possible. The remaining doses should be adjusted accordingly to maintain the 7-day dosing schedule. If more than one day is missed, consult with your healthcare team about the best approach, which may involve extending the dosing period or modifying the cycle.
Overdose
There is no specific antidote for azacitidine overdose. In the event of an overdose, the patient should be monitored with appropriate blood counts and receive supportive treatment as necessary. One case of overdose with azacitidine was reported during clinical trials after a single intravenous dose of approximately 290 mg/m², nearly four times the recommended starting dose. The patient experienced diarrhoea, nausea, and vomiting; no long-term sequelae were observed. In case of overdose, contact your local poison centre or emergency services immediately.
What Are the Side Effects of Azacitidine Tillomed?
Like all medicines, Azacitidine Tillomed can cause side effects, although not everybody gets them. The most frequently reported side effects are related to bone marrow suppression (myelosuppression), which is an expected effect of the drug's mechanism of action. Gastrointestinal side effects and injection site reactions are also very common. The severity and frequency of side effects may vary between patients and treatment cycles.
Side effects are classified below by frequency according to international convention. The frequency categories are based on data from clinical trials and post-marketing surveillance:
Very Common
Affects more than 1 in 10 patients (>10%)
- Neutropenia (low white blood cells) — increases infection risk
- Thrombocytopenia (low platelets) — increases bleeding risk
- Anaemia (low red blood cells) — causes fatigue, pallor, breathlessness
- Leukopenia (low total white blood cells)
- Pneumonia and upper respiratory tract infections
- Urinary tract infections
- Nausea and vomiting
- Diarrhoea and constipation
- Injection site reactions (redness, pain, bruising, induration, swelling)
- Fatigue, pyrexia (fever), and weakness
- Decreased appetite and weight loss
- Dizziness and headache
- Dyspnoea (shortness of breath)
- Arthralgia (joint pain)
- Petechiae (small red spots on the skin)
Common
Affects 1 to 10 in 100 patients (1–10%)
- Febrile neutropenia (fever with very low white blood cells)
- Sepsis (severe bloodstream infection)
- Nasopharyngitis (common cold)
- Abdominal pain and stomatitis (mouth sores)
- Epistaxis (nosebleeds)
- Rash, pruritus (itching), and ecchymosis (bruising)
- Insomnia and anxiety
- Myalgia (muscle pain) and back pain
- Hypokalemia (low potassium) and hyponatraemia (low sodium)
- Elevated liver enzymes (ALT, AST) and elevated creatinine
- Chest pain and peripheral oedema
- Hypotension (low blood pressure)
Uncommon
Affects 1 to 10 in 1,000 patients (0.1–1%)
- Renal tubular acidosis
- Renal failure
- Tumour lysis syndrome
- Interstitial lung disease
- Sweet syndrome (acute febrile neutrophilic dermatosis)
- Pyoderma gangrenosum (inflammatory skin condition)
Rare
Affects 1 to 10 in 10,000 patients (0.01–0.1%)
- Hepatic coma and hepatic failure (primarily in patients with extensive tumour burden)
- Necrotising fasciitis (severe soft tissue infection)
- Differentiation syndrome
Contact your doctor or seek emergency medical care immediately if you experience: fever above 38°C (100.4°F) or signs of infection (especially if you know your white blood cell count is low), unusual bleeding or bruising, blood in urine or stool, severe abdominal pain, difficulty breathing, severe skin reactions, signs of liver problems (yellowing of skin or eyes, dark urine), or decreased urine output. These may be signs of serious side effects requiring urgent medical treatment.
It is important to note that many patients experience worsening of their blood counts during the first 1–2 treatment cycles before improvement occurs. This initial worsening is expected and does not necessarily mean the treatment is not working. The bone marrow needs time to respond to the hypomethylating effects of azacitidine, which is why a minimum of 6 treatment cycles is recommended before assessing response. Supportive care, including blood transfusions and antibiotics when needed, is an essential part of azacitidine treatment.
How Should You Store Azacitidine Tillomed?
Proper storage of Azacitidine Tillomed is essential to maintain the drug's stability and efficacy. The following storage instructions apply:
- Unopened vials: Store below 25°C (77°F). Do not freeze. Keep the vial in the outer carton to protect from light.
- After reconstitution: The reconstituted suspension has limited stability. If stored at room temperature (15–25°C), it should be administered within 45 minutes. If refrigerated at 2–8°C (36–46°F), the reconstituted product may be stored for up to 8 hours. When removed from the refrigerator, allow the suspension to equilibrate to room temperature for approximately 30 minutes before injection.
- Do not use if the reconstituted suspension contains large particles or aggregates that do not disperse upon gentle rolling of the syringe between the palms.
- Keep out of the sight and reach of children.
- Do not use after the expiry date printed on the vial label and carton.
Azacitidine Tillomed is a cytotoxic medicine and should be handled with appropriate precautions for hazardous substances. Healthcare professionals should wear protective gloves when preparing and administering the injection. Any unused medicine or waste material should be disposed of in accordance with local requirements for cytotoxic waste.
What Does Azacitidine Tillomed Contain?
Understanding the composition of your medicine helps both patients and healthcare professionals ensure safe and appropriate use:
Active substance: Each vial contains 100 mg of azacitidine. After reconstitution with 4 ml of water for injections, the resulting suspension contains 25 mg/ml of azacitidine. Azacitidine (chemical name: 4-amino-1-β-D-ribofuranosyl-1,3,5-triazin-2(1H)-one) is a white to off-white powder with a molecular weight of 244.2 g/mol.
Other ingredient (excipient): Mannitol (E421). Mannitol is a sugar alcohol used as a bulking agent in the lyophilised (freeze-dried) powder formulation. It helps ensure uniform distribution and proper reconstitution of the azacitidine. Mannitol is generally well tolerated, but patients with rare hereditary fructose intolerance should be aware of its presence.
Pharmaceutical form: Azacitidine Tillomed is a white lyophilised powder for suspension for injection. After reconstitution with the appropriate volume of water for injections, it forms a uniform, cloudy suspension. The suspension is for subcutaneous injection only and should not be administered intravenously through this formulation.
Appearance: The reconstituted suspension is a cloudy white suspension. A small amount of undissolved particles is acceptable as long as no large particles or aggregates are present. The suspension should be gently rolled (not shaken vigorously) between the palms to achieve a uniform, cloudy suspension before drawing up into the syringe.
Frequently Asked Questions About Azacitidine Tillomed
Azacitidine Tillomed is used to treat adults with myelodysplastic syndromes (MDS), including higher-risk types such as refractory anaemia with excess blasts, chronic myelomonocytic leukaemia (CMML) with 10–29% bone marrow blasts, and acute myeloid leukaemia (AML) with 20–30% blasts and multi-lineage dysplasia. It is also used for AML patients aged 65 and older with more than 30% blasts who are not candidates for intensive chemotherapy. The drug works by reversing abnormal DNA methylation patterns that silence tumour suppressor genes, helping to restore normal blood cell production.
Azacitidine Tillomed is administered as a subcutaneous (under the skin) injection, typically in the upper arm, thigh, or abdomen. The injection is given by a healthcare professional in a hospital or outpatient clinic. The standard schedule is a daily injection for 7 consecutive days, followed by a 21-day rest period, forming a 28-day treatment cycle. Injection sites should be rotated between the three areas to minimise injection site reactions.
Azacitidine typically requires several treatment cycles before the full benefit becomes apparent. Most patients do not show meaningful improvement until after at least 4–6 cycles of treatment. Blood counts may initially worsen during the first 1–2 cycles before improving, as the drug needs time to reprogram the bone marrow through its hypomethylating effect. This is why international guidelines recommend a minimum of 6 treatment cycles before concluding that the treatment is ineffective. Some patients may require even longer to achieve their best response.
Regular blood monitoring is essential during azacitidine treatment. Complete blood counts (CBC) should be performed before each treatment cycle to check levels of neutrophils, platelets, and haemoglobin. Liver function tests (ALT, AST, bilirubin) and kidney function tests (serum creatinine, electrolytes, bicarbonate) should also be monitored before each cycle. Your doctor will use these results to determine whether it is safe to proceed with the next cycle or if dose adjustments are needed. More frequent blood testing may be required during the first few cycles.
Azacitidine Tillomed is a generic version of the original brand-name product Vidaza. Both medicines contain exactly the same active ingredient (azacitidine) at the same concentration (25 mg/ml after reconstitution) and are given in exactly the same way (subcutaneous injection). Generic medicines must meet the same rigorous quality, safety, and efficacy standards as the originator product to receive marketing authorisation from the European Medicines Agency (EMA). The main difference is the manufacturer: Vidaza is produced by Bristol-Myers Squibb (Celgene), while Azacitidine Tillomed is produced by Tillomed Pharma.
While there is no specific formal interaction between azacitidine and alcohol, it is generally advisable to limit or avoid alcohol during treatment. Azacitidine can affect liver function, and alcohol adds additional stress to the liver. Alcohol can also worsen common side effects such as nausea, fatigue, and dehydration, and may further suppress the immune system. Discuss your alcohol consumption with your treating physician for personalised advice based on your overall health status and liver function.
References
- European Medicines Agency (EMA). Azacitidine Tillomed – Summary of Product Characteristics. Available at: www.ema.europa.eu. Accessed December 2025.
- Fenaux P, Mufti GJ, Hellström-Lindberg E, et al. Efficacy of azacitidine compared with that of conventional care regimens in the treatment of higher-risk myelodysplastic syndromes: a randomised, open-label, phase III study. The Lancet Oncology. 2009;10(3):223-232. doi:10.1016/S1470-2045(09)70003-8
- Dombret H, Seymour JF, Butrym A, et al. International phase 3 study of azacitidine vs conventional care regimens in older patients with newly diagnosed AML with >30% blasts. Blood. 2015;126(3):291-299. doi:10.1182/blood-2015-01-621664
- National Comprehensive Cancer Network (NCCN). Clinical Practice Guidelines in Oncology: Myelodysplastic Syndromes. Version 1.2025. Available at: www.nccn.org.
- European Society for Medical Oncology (ESMO). Myelodysplastic Syndromes: ESMO Clinical Practice Guidelines. Annals of Oncology. 2024. doi:10.1016/j.annonc.2024.01.002
- Silverman LR, Demakos EP, Peterson BL, et al. Randomized controlled trial of azacitidine in patients with the myelodysplastic syndrome: a study of the cancer and leukemia group B. Journal of Clinical Oncology. 2002;20(10):2429-2440. doi:10.1200/JCO.2002.04.117
- World Health Organization (WHO). Model List of Essential Medicines, 23rd List, 2023. Available at: www.who.int.
- U.S. Food and Drug Administration (FDA). Vidaza (azacitidine) Prescribing Information. Revised 2024. Available at: www.fda.gov.
- British National Formulary (BNF). Azacitidine Monograph. Available at: bnf.nice.org.uk. Accessed December 2025.
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