Myocet (Non-pegylated liposomal)

Doxorubicin (Liposomal) (50mg)
Price: Approx. ₹15,000 - ₹20,000 per vial (Note: Myocet is a non-pegylated formulation with different pharmacokinetics and approved indications, primarily for metastatic breast cancer in combination with cyclophosphamide)
Mfr: Zydus Cadila (Marketed in India) | Form: Lyophilized Powder and Solvent for Injection

📋 Clinical Overview

Doxorubicin (Liposomal) is a pegylated, liposome-encapsulated formulation of the anthracycline antibiotic doxorubicin. This formulation is designed to enhance drug delivery to tumor sites while reducing systemic exposure and certain toxicities, most notably cardiotoxicity and palmar-plantar erythrodysesthesia (hand-foot syndrome), compared to conventional doxorubicin. It represents a critical chemotherapeutic agent in the Indian oncology landscape.

💊 Dosage & Administration

Adult: Dose is based on body surface area (BSA). **AIDS-KS:** 20 mg/m² IV over 30 minutes every 2-3 weeks. **Ovarian Cancer:** 50 mg/m² IV over 60 minutes every 4 weeks. **Multiple Myeloma:** 30 mg/m² IV over 60 minutes on day 4 following bortezomib (which is given on days 1, 4, 8, & 11 of a 21-day cycle).

Note: FOR INTRAVENOUS INFUSION ONLY. MUST NOT BE GIVEN INTRAMUSCULARLY OR SUBCUTANEOUSLY. Do not mix with other drugs. Dilute in 250 mL of 5% Dextrose Injection (preferred) to minimize aggregation. Do not use saline or any other diluent. Administer using a dedicated IV line at a controlled rate (as per indication) using an infusion pump. Observe for extravasation, which can cause severe local tissue damage.

⚠️ Contraindications

  • History of severe hypersensitivity reaction to doxorubicin, other anthracyclines, or any component of the liposomal formulation (including polyethylene glycol/PEG).
  • Baseline neutrophil count < 1,500 cells/mm³ (for most regimens).
  • Severe myocardial insufficiency, recent myocardial infarction, or cardiomyopathy with impaired cardiac function (LVEF below institutional lower limit of normal).

🔬 Mechanism of Action

The liposomal formulation delivers doxorubicin to tumor sites via the Enhanced Permeability and Retention (EPR) effect. Once internalized by tumor cells and doxorubicin is released, it intercalates into DNA base pairs, causing uncoiling of the DNA helix. This inhibits the progression of the enzyme topoisomerase II, which is required for DNA replication and repair, leading to DNA strand breaks and inhibition of nucleic acid synthesis.

🤕 Side Effects

  • Myelosuppression (Neutropenia, Leukopenia, Anemia, Thrombocytopenia)
  • Nausea and Vomiting (less severe than conventional doxorubicin)
  • Stomatitis/Mucositis
  • Alopecia (reversible, less frequent than conventional)
  • Fatigue/Asthenia
  • Palmar-Plantar Erythrodysesthesia (Hand-Foot Syndrome) - dose limiting
  • Diarrhea or Constipation

🤰 Special Populations

Pregnancy: **FDA Pregnancy Category D.** Doxorubicin can cause fetal harm. It is embryotoxic and teratogenic. Not recommended during pregnancy. Effective contraception is required for both males and females during and for at least 6 months after therapy.

Driving: May cause fatigue, dizziness, or malaise. Patients should be cautioned about driving or operating machinery if affected.

🔄 Drug Interactions

Trastuzumab, CyclophosphamideMarkedly increased risk of cardiotoxicity (congestive heart failure, decreased LVEF).Major
Other Myelosuppressive Agents (e.g., Paclitaxel, Gemcitabine)Additive bone marrow suppression. Monitor blood counts closely.Major
Phenobarbital, PhenytoinIncreased hepatic metabolism of doxorubicin, potentially reducing its efficacy.Moderate
Live Vaccines (e.g., MMR, Varicella)Risk of disseminated infection due to immunosuppression. Avoid.Major
DexrazoxaneCardioprotective agent used to reduce the risk of doxorubicin-induced cardiomyopathy.Beneficial Interaction

🔁 Alternatives to Myocet (Non-pegylated liposomal)

Same composition (Doxorubicin (Liposomal) (50mg)), different brands:

Doxolip Lipodox