Myocet Liposomal (Doxorubicin)
Non-pegylated liposomal doxorubicin for metastatic breast cancer
Quick Facts About Myocet Liposomal
Key Takeaways
- Myocet liposomal contains doxorubicin encapsulated in non-pegylated liposomes, reducing cardiotoxicity while preserving anticancer activity against metastatic breast cancer.
- It is approved for first-line treatment of metastatic breast cancer in adult women, given in combination with cyclophosphamide at a dose of 60–75 mg/m² every 3 weeks.
- Myocet liposomal must NOT be substituted with other doxorubicin formulations (conventional or pegylated liposomal), as their pharmacokinetics and safety profiles differ significantly.
- Regular cardiac monitoring (echocardiography or MUGA scan) is essential before and during treatment, as cumulative anthracycline exposure increases the risk of heart failure.
- The most common side effects include myelosuppression (neutropenia, anaemia), nausea, vomiting, alopecia, and stomatitis — most are manageable with dose adjustments and supportive care.
What Is Myocet Liposomal and What Is It Used For?
Myocet liposomal belongs to the anthracycline class of antineoplastic antibiotics, which are among the most effective and widely used chemotherapy agents worldwide. The active substance, doxorubicin hydrochloride, works by intercalating into the DNA of rapidly dividing cancer cells, inhibiting the enzyme topoisomerase II, and generating free radicals. These combined mechanisms disrupt DNA replication and transcription, ultimately leading to cancer cell death through apoptosis.
What distinguishes Myocet liposomal from conventional (free) doxorubicin is its delivery system. The doxorubicin is encapsulated within non-pegylated liposomes — tiny lipid vesicles that are structurally similar to cell membranes. This liposomal encapsulation fundamentally alters how the drug is distributed throughout the body. The liposomes preferentially accumulate in tumour tissue through a phenomenon known as the enhanced permeability and retention (EPR) effect, which exploits the leaky vasculature and poor lymphatic drainage characteristic of solid tumours.
The European Medicines Agency (EMA) granted marketing authorisation for Myocet liposomal specifically for use in combination with cyclophosphamide for the first-line treatment of metastatic breast cancer in adult women. This combination regimen has demonstrated equivalent overall response rates and comparable overall survival outcomes to conventional doxorubicin plus cyclophosphamide (AC regimen), while significantly reducing the incidence and severity of cardiotoxicity.
It is important to understand that Myocet liposomal is distinct from pegylated liposomal doxorubicin (marketed as Caelyx or Doxil in various regions). While both are liposomal formulations of doxorubicin, they differ in their liposome composition, pharmacokinetic properties, approved indications, dosing schedules, and side effect profiles. These formulations are not interchangeable, and substituting one for another could result in serious adverse effects or therapeutic failure.
What Should You Know Before Taking Myocet Liposomal?
Before starting treatment with Myocet liposomal, your oncologist will conduct a thorough assessment of your overall health, heart function, liver function, and blood counts. This evaluation is essential because doxorubicin, even in its liposomal form, can affect multiple organ systems, and certain pre-existing conditions may increase the risk of serious adverse effects. Understanding these considerations helps ensure the safest and most effective use of this medication.
Contraindications
Myocet liposomal must not be used in the following situations:
- Hypersensitivity to doxorubicin hydrochloride, other anthracyclines, anthracenediones, or any of the excipients contained in the formulation.
- Severe hepatic impairment — significantly reduced liver function impairs the metabolism and elimination of doxorubicin, leading to increased drug exposure and heightened toxicity risk.
- Severe myocardial insufficiency — patients with advanced heart failure (NYHA Class IV) or severe cardiac dysfunction have unacceptable risk of further cardiac deterioration.
- Previous maximum cumulative doses of doxorubicin, daunorubicin, epirubicin, idarubicin, or other anthracyclines and anthracenediones.
- Persistent myelosuppression or severe concurrent infections that have not resolved.
- Breastfeeding — doxorubicin is excreted in breast milk and could cause serious harm to a nursing infant.
Warnings and Precautions
Several important warnings apply to the use of Myocet liposomal. Your healthcare team will monitor you closely for these potential risks throughout your treatment course:
Cardiotoxicity: The most clinically significant risk associated with anthracyclines is cardiotoxicity, which can manifest as acute effects (arrhythmias, ECG changes) or chronic cardiomyopathy that may progress to congestive heart failure. The risk increases with cumulative dose. While Myocet liposomal has demonstrated lower cardiotoxicity rates than conventional doxorubicin in clinical trials, the risk is not eliminated. Cardiac function should be assessed by echocardiography or MUGA scan before treatment initiation, and monitoring should continue regularly throughout therapy and for years after treatment completion.
Myelosuppression: Doxorubicin causes dose-dependent suppression of bone marrow function, leading to neutropenia, thrombocytopenia, and anaemia. Neutropenia is typically the dose-limiting toxicity, with the nadir occurring approximately 10–14 days after administration. Complete blood counts should be obtained before each treatment cycle. Febrile neutropenia is a potentially life-threatening complication requiring prompt medical attention and broad-spectrum antibiotic therapy.
Hepatotoxicity: Doxorubicin is primarily metabolised and eliminated by the liver. Patients with impaired hepatic function may experience increased drug exposure, heightened toxicity, and delayed clearance. Liver function tests should be performed before each cycle, and dose reductions are necessary for patients with elevated bilirubin levels.
Secondary malignancies: The use of anthracycline-based chemotherapy has been associated with an increased risk of developing secondary malignancies, particularly acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS), typically occurring 1–3 years after treatment.
Pregnancy and Breastfeeding
Myocet liposomal must not be used during pregnancy unless the potential benefit to the mother clearly outweighs the risk to the foetus. Doxorubicin is genotoxic and has demonstrated embryotoxic and teratogenic effects in animal studies. Women of childbearing potential must use effective contraception during treatment and for at least 6.5 months after the last dose. Male patients with female partners of childbearing potential should use effective contraception during treatment and for at least 3.5 months after the last dose.
Breastfeeding is contraindicated during treatment with Myocet liposomal and for at least 2 weeks after the last dose. Doxorubicin and its metabolites have been detected in breast milk, and there is a risk of serious adverse reactions in breastfed infants. Women should be advised to discontinue breastfeeding before starting therapy.
Fertility: Doxorubicin may cause irreversible infertility in both men and women. Men should be counselled about sperm preservation before initiating treatment. Women should be informed about the potential impact on ovarian function, and fertility preservation options should be discussed prior to starting chemotherapy.
How Does Myocet Liposomal Interact with Other Drugs?
Drug interactions with Myocet liposomal can affect the drug's efficacy, alter its metabolism, or increase the risk of adverse effects. Because doxorubicin is metabolised by the liver (primarily via CYP3A4 and CYP2D6 enzymes) and eliminated in bile, medications that affect hepatic enzyme activity can significantly alter doxorubicin exposure. Furthermore, because doxorubicin affects the heart and bone marrow, concurrent use of other cardiotoxic or myelosuppressive agents requires careful monitoring.
Major Interactions
| Interacting Drug | Effect | Clinical Significance |
|---|---|---|
| Trastuzumab (Herceptin) | Significantly increased risk of cardiotoxicity and congestive heart failure | Avoid concurrent use. If sequential use is needed, cardiac monitoring is essential with a washout period of at least 7 months. |
| Ciclosporin | Increased doxorubicin plasma levels due to inhibition of CYP3A4 and P-glycoprotein; increased myelosuppression | May require dose reduction of Myocet liposomal. Monitor blood counts closely. |
| Paclitaxel | Reduced doxorubicin clearance when paclitaxel is administered before doxorubicin; increased neutropenia and stomatitis | If combination is necessary, administer Myocet liposomal before paclitaxel. |
| Live vaccines | Risk of severe, potentially fatal infections due to immunosuppression | Live vaccines are contraindicated during chemotherapy and for at least 3–6 months after completion. |
| Other anthracyclines | Cumulative cardiotoxicity; increased risk of congestive heart failure | Maximum cumulative dose limits must account for ALL prior anthracycline exposure. |
Other Interactions
| Interacting Drug | Effect | Management |
|---|---|---|
| Phenobarbital / Phenytoin | Increased doxorubicin clearance via CYP3A4 induction; reduced efficacy | Monitor treatment response. Dose adjustment may be needed. |
| Digoxin | Reduced digoxin absorption; altered oral bioavailability due to mucosal damage | Monitor digoxin levels during concurrent use. |
| Calcium channel blockers | Potential increased doxorubicin accumulation in cardiac tissue | Enhanced cardiac monitoring recommended. |
| Warfarin | Altered anticoagulant effect; unpredictable changes in INR | Frequent INR monitoring; consider switching to LMWH. |
Patients should inform their oncology team about all medications they are taking, including prescription drugs, over-the-counter medicines, herbal supplements, and vitamins. St. John’s Wort (Hypericum perforatum) is a potent CYP3A4 inducer and may significantly reduce doxorubicin plasma levels, potentially compromising treatment efficacy. Grapefruit juice should also be avoided as it inhibits CYP3A4 and may increase doxorubicin exposure.
What Is the Correct Dosage of Myocet Liposomal?
Myocet liposomal must be prescribed and administered under the supervision of a qualified oncologist experienced in the use of antineoplastic chemotherapy. The dose is calculated based on the patient's body surface area (BSA), which takes into account both height and weight. The reconstitution of the product is a multi-step process that must be performed by trained healthcare professionals to ensure correct liposome formation and drug encapsulation.
Adults
Standard Adult Dosing
The recommended dose of Myocet liposomal is 60–75 mg/m² administered as an intravenous infusion over approximately 1 hour, every 21 days (3 weeks), in combination with intravenous cyclophosphamide 600 mg/m² on the same day. Treatment cycles are repeated until disease progression or unacceptable toxicity occurs.
The number of treatment cycles depends on the patient's response and tolerability. Clinical trials typically administered 6–8 cycles. Dose modifications may be required based on haematological toxicity, hepatic function, and cardiac status.
Dose Adjustments
| Condition | Adjustment | Details |
|---|---|---|
| Hepatic impairment (bilirubin 1.2–3 mg/dL) | 50% dose reduction | Monitor liver function closely each cycle |
| Hepatic impairment (bilirubin >3 mg/dL) | 75% dose reduction | Use only if benefit outweighs risk; consider alternatives |
| Neutropenia (ANC <1,500/µL) | Delay treatment | Delay until ANC recovers to ≥1,500/µL; consider G-CSF support |
| Febrile neutropenia or Grade 4 neutropenia (>7 days) | 25% dose reduction | Consider G-CSF prophylaxis in subsequent cycles |
| Cardiac decline (LVEF drop ≥20% or below LLN) | Discontinue treatment | If LVEF declines significantly, treatment should be stopped |
Children and Adolescents
Myocet liposomal is not indicated for use in children and adolescents under 18 years of age. The safety and efficacy of this formulation have not been established in paediatric populations. Alternative doxorubicin formulations and treatment protocols exist for paediatric oncology indications and should be used under specialist guidance.
Elderly Patients
No specific dose adjustment is required for elderly patients based solely on age. However, elderly patients may have reduced cardiac reserve, decreased hepatic and renal function, and lower bone marrow reserve compared to younger adults. These factors should be taken into account when determining the initial dose and during ongoing treatment monitoring. Cardiac function assessment is particularly important in elderly patients, as the risk of doxorubicin-induced cardiotoxicity is higher in this population.
Missed Dose
Since Myocet liposomal is administered in a hospital or clinic setting by healthcare professionals, missed doses are uncommon. If a scheduled treatment cycle is delayed due to adverse effects or logistical reasons, the next dose should be administered as soon as the patient has recovered sufficiently (adequate blood counts, resolved infection, stable cardiac function). The treating oncologist will determine the appropriate timing for the next cycle. Dose schedules should not be “made up” by doubling the dose or shortening the interval between cycles.
Overdose
Acute overdose of doxorubicin may lead to severe and potentially life-threatening complications including severe myelosuppression (particularly neutropenia and thrombocytopenia, reaching nadir within 10–14 days), severe mucositis, and acute cardiac toxicity. There is no specific antidote for doxorubicin overdose. Management is supportive and may include:
- Hospitalisation in an intensive care setting with haematological monitoring
- Platelet and granulocyte transfusions as clinically indicated
- Broad-spectrum antibiotics for neutropenic sepsis
- Cardiac monitoring and management of arrhythmias or heart failure
- Dexrazoxane may be considered as a cardioprotective agent in certain acute overdose scenarios
What Are the Side Effects of Myocet Liposomal?
Like all chemotherapy agents, Myocet liposomal can cause side effects. Not everyone who receives this medication will experience all of these effects, and severity varies between individuals. The side effects are largely attributable to the cytotoxic activity of doxorubicin on rapidly dividing normal cells, including bone marrow cells, gastrointestinal mucosa, and hair follicles. However, the liposomal formulation provides meaningful clinical advantages: phase III clinical trials demonstrated that Myocet liposomal in combination with cyclophosphamide resulted in significantly fewer cardiac events (including a 78% reduction in clinical heart failure) compared to conventional doxorubicin plus cyclophosphamide.
The side effects are categorised below according to their frequency of occurrence, based on data from clinical trials and post-marketing surveillance:
Very Common
- Neutropenia (low white blood cell count) — the most frequent dose-limiting toxicity
- Anaemia (low red blood cell count)
- Leukopenia (low total white blood cell count)
- Nausea and vomiting
- Alopecia (hair loss) — typically begins 2–3 weeks after first dose; usually reversible
- Fatigue and asthenia (weakness)
- Stomatitis and oral mucositis (mouth inflammation and sores)
- Infections (due to immunosuppression)
- Decreased appetite and anorexia
Common
- Thrombocytopenia (low platelet count)
- Febrile neutropenia (fever with low white blood cells)
- Diarrhoea or constipation
- Abdominal pain
- Peripheral neuropathy (numbness/tingling in hands and feet)
- Headache and dizziness
- Skin rash and pruritus (itching)
- Nail changes (discolouration, ridging)
- Oedema (swelling)
- Dyspnoea (shortness of breath)
- Elevated liver enzymes (transaminases)
- Injection site reactions
Uncommon
- Cardiomyopathy and congestive heart failure
- Arrhythmias (irregular heartbeat)
- Severe sepsis
- Pneumonia
- Severe mucositis requiring hospitalisation
- Dehydration
- Hyperpigmentation of skin and nails
- Palmar-plantar erythrodysaesthesia (hand-foot syndrome)
Rare
- Anaphylactic/anaphylactoid reactions
- Secondary acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS)
- Severe cardiac failure leading to death
- Myocardial infarction
- Severe hepatotoxicity
- Tumour lysis syndrome
- Radiation recall dermatitis
How Should You Store Myocet Liposomal?
Myocet liposomal is a hospital-only medicine that is stored, reconstituted, and administered by trained healthcare professionals. Patients will not typically handle or store this medication at home. However, understanding proper storage requirements is important for ensuring the medication remains effective and safe.
Before reconstitution: The unopened components (doxorubicin hydrochloride powder, liposomes, and buffer solution) should be stored in a refrigerator at 2–8°C (36–46°F). Do not freeze. Keep the vials in the original carton to protect from light.
After reconstitution: The reconstituted Myocet liposomal dispersion for infusion should be stored in a refrigerator at 2–8°C and used within 8 hours of preparation. Chemical and physical in-use stability has been demonstrated for up to 8 hours at 2–8°C. From a microbiological standpoint, the product should be used immediately after preparation. If not used immediately, in-use storage times and conditions are the responsibility of the user.
During administration: The reconstituted product should be allowed to reach room temperature before infusion. Once prepared for infusion and at room temperature, it should be administered as soon as possible.
Disposal: Any unused medicinal product or waste material should be disposed of in accordance with local requirements for cytotoxic waste. Myocet liposomal is a hazardous medicinal product, and appropriate precautions for handling and disposal must be followed, including the use of personal protective equipment (gloves, gowns, eye protection) during preparation and administration.
What Does Myocet Liposomal Contain?
Myocet liposomal is a multi-component product that requires reconstitution before use. Understanding its composition is important for healthcare professionals preparing the medication and for patients with known allergies to any of the components.
Active substance:
- Doxorubicin hydrochloride — 50 mg per vial
The product consists of three separate components:
- Myocet liposomal doxorubicin HCl: A red-orange lyophilised powder containing doxorubicin hydrochloride and lactose monohydrate.
- Myocet liposomal liposomes: A white to off-white, opaque, homogeneous dispersion containing egg phosphatidylcholine, cholesterol, citric acid, sodium hydroxide, and water for injections. These lipids form the liposomal bilayer that encapsulates the doxorubicin.
- Myocet liposomal buffer: A clear, colourless solution containing sodium carbonate, water for injections, and hydrochloric acid for pH adjustment.
The liposomes in Myocet liposomal are non-pegylated, meaning they do not have a polyethylene glycol (PEG) coating. This is a key distinction from pegylated liposomal doxorubicin products. The absence of PEGylation results in different pharmacokinetics, with a shorter circulation time but reduced risk of PEG-related hypersensitivity reactions such as complement activation-related pseudoallergy (CARPA).
Frequently Asked Questions About Myocet Liposomal
Both Myocet liposomal and Caelyx (known as Doxil in the United States) contain doxorubicin encapsulated in liposomes, but they are fundamentally different products. Myocet liposomal uses non-pegylated liposomes, while Caelyx uses pegylated (PEG-coated) liposomes. This difference in liposome coating significantly affects how the drugs behave in the body. Caelyx has a much longer circulation time (days vs. hours), different approved indications (ovarian cancer, Kaposi's sarcoma, multiple myeloma), different dosing schedules, and a different side effect profile — notably, Caelyx is more commonly associated with palmar-plantar erythrodysaesthesia (hand-foot syndrome). These two products are not interchangeable.
Treatment duration varies depending on the individual patient's response and tolerability. In clinical trials, patients typically received 6–8 cycles of Myocet liposomal in combination with cyclophosphamide, with each cycle lasting 21 days (3 weeks). Treatment may be continued beyond 8 cycles if the patient is responding well and tolerating the therapy, or it may be shortened if the cancer progresses or side effects become unacceptable. Your oncologist will assess your response using imaging scans and clinical evaluation at regular intervals to determine the optimal treatment duration.
Yes, in the vast majority of patients, hair loss (alopecia) caused by doxorubicin-based chemotherapy is temporary and reversible. Hair typically begins to fall out 2–3 weeks after the first treatment cycle and may continue throughout the treatment course. Hair regrowth usually begins within 1–3 months after the final treatment cycle. Initially, the new hair may have a different texture or colour, but it generally returns to its pre-treatment characteristics over time. Scalp cooling (cold caps) during chemotherapy infusions may help reduce the extent of hair loss in some patients.
Clinical evidence strongly supports that Myocet liposomal has a significantly better cardiac safety profile compared to conventional doxorubicin. In the pivotal phase III clinical trial, the combination of Myocet liposomal with cyclophosphamide resulted in a 78% reduction in the rate of clinical congestive heart failure compared to conventional doxorubicin with cyclophosphamide, while maintaining comparable anticancer efficacy. However, it is important to note that cardiac risk is not completely eliminated. Regular cardiac monitoring remains essential, and cumulative dose limits must still be respected.
Prior anthracycline exposure is a critical factor in determining whether Myocet liposomal can be safely administered. All previous cumulative doses of anthracyclines (doxorubicin, epirubicin, daunorubicin, idarubicin, and anthracenediones like mitoxantrone) must be documented and calculated. If you have already reached or are close to the maximum recommended cumulative dose, Myocet liposomal may be contraindicated due to unacceptable cardiac risk. Your oncologist will carefully evaluate your treatment history, current cardiac function, and overall clinical situation before making a decision. Baseline cardiac assessment with echocardiography or MUGA scan is mandatory in this scenario.
Fever during chemotherapy is a medical emergency that requires immediate attention. If you develop a temperature of 38°C (100.4°F) or higher, or if you feel unwell between treatment cycles, you should contact your oncology team or go to the emergency department immediately. Fever in the setting of neutropenia (febrile neutropenia) can indicate a serious, potentially life-threatening infection. Blood cultures and complete blood counts will be performed, and you may be started on broad-spectrum intravenous antibiotics. Never take paracetamol (acetaminophen) or ibuprofen to self-treat a fever during chemotherapy without first contacting your medical team, as these medications can mask important clinical signs.
References
All medical information on this page is based on evidence from peer-reviewed research, international clinical guidelines, and regulatory documentation. The following sources were used:
- European Medicines Agency (EMA). Myocet liposomal — Summary of Product Characteristics (SmPC). Last updated 2024. Available at: ema.europa.eu
- Batist G, Ramakrishnan G, Rao CS, et al. Reduced cardiotoxicity and preserved antitumor efficacy of liposome-encapsulated doxorubicin and cyclophosphamide compared with conventional doxorubicin and cyclophosphamide in a randomized, multicenter trial of metastatic breast cancer. Journal of Clinical Oncology. 2001;19(5):1444–1454. doi:10.1200/JCO.2001.19.5.1444
- Harris L, Batist G, Belt R, et al. Liposome-encapsulated doxorubicin compared with conventional doxorubicin in a randomized multicenter trial as first-line therapy of metastatic breast cancer. Cancer. 2002;94(1):25–36. doi:10.1002/cncr.10201
- ESMO Clinical Practice Guidelines. Metastatic Breast Cancer: ESMO Clinical Practice Guidelines for Diagnosis, Treatment and Follow-up. Annals of Oncology. 2024;35(2):159–182.
- Cardoso F, Paluch-Shimon S, Senkus E, et al. 5th ESO-ESMO international consensus guidelines for advanced breast cancer (ABC 5). Annals of Oncology. 2020;31(12):1623–1649. doi:10.1016/j.annonc.2020.09.010
- World Health Organization (WHO). WHO Model List of Essential Medicines — 23rd List. Geneva: WHO; 2023.
- National Comprehensive Cancer Network (NCCN). NCCN Clinical Practice Guidelines in Oncology: Breast Cancer. Version 2.2024.
- Swain SM, Whaley FS, Ewer MS. Congestive heart failure in patients treated with doxorubicin: a retrospective analysis of three trials. Cancer. 2003;97(11):2869–2879. doi:10.1002/cncr.11407
- British National Formulary (BNF). Doxorubicin hydrochloride. NICE Evidence Services. Accessed January 2026.
Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, comprising licensed physicians and pharmacists with specialist expertise in oncology and clinical pharmacology. All medical content follows the GRADE evidence framework and adheres to international guidelines from the WHO, EMA, ESMO, and NCCN.
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iMedic Medical Editorial Team
Specialists in Clinical Pharmacology & Oncology
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iMedic Medical Review Board
Independent review panel following WHO, EMA, ESMO guidelines
Evidence Standard: All medical claims in this article are supported by Level 1A evidence (systematic reviews and meta-analyses of randomised controlled trials) or official regulatory documentation (EMA SmPC). Last fact-checked: .