Epirubicin hydrochloride is a semi-synthetic anthracycline antibiotic and cytotoxic antineoplastic agent. It is the 4'-epimer of doxorubicin, differing only in the stereochemical configuration of the hydroxyl group at the 4' position of the sugar moiety. This structural modification results in a distinct pharmacokinetic and toxicity profile, with a potentially improved therapeutic index in certain malignancies. It is a cell cycle non-specific agent, primarily active against proliferating cells.
Adult: Dose is individualized based on BSA, regimen, and indication. Common regimens: 1) Breast Cancer (Adjuvant): 100-120 mg/m² intravenously every 3-4 weeks. 2) Breast Cancer (Metastatic): 75-90 mg/m² every 3 weeks. 3) Other Cancers: Typically 60-120 mg/m² as part of combination therapy. Dose reductions are mandatory for hematologic toxicity, hepatic dysfunction, or mucositis.
Note: For IV use ONLY. Administer as a slow intravenous push or infusion over 15-20 minutes into the side port of a freely running intravenous infusion of 0.9% Sodium Chloride or 5% Dextrose. NEVER give IM or SC. MUST be administered by personnel trained in cytotoxic drug handling. Strict aseptic technique. Vigilant monitoring for extravasation is mandatory. Pre-medication with antiemetics is standard.
Epirubicin exerts its cytotoxic effects through multiple mechanisms: 1) Intercalation into DNA base pairs, causing steric obstruction of DNA and RNA synthesis. 2) Inhibition of the enzyme topoisomerase II, leading to DNA double-strand breaks. 3) Generation of reactive oxygen species (ROS) and free radicals via iron-mediated redox cycling, causing oxidative damage to cellular membranes, proteins, and DNA. 4) Induction of apoptosis (programmed cell death).
Pregnancy: FDA Pregnancy Category D. Can cause fetal harm. Teratogenic and embryotoxic in animals. Not recommended. A pregnancy test should be performed in women of childbearing potential before initiation. Effective contraception is mandatory during and for at least 6 months after therapy.
Driving: May cause fatigue, dizziness, or malaise. Patients should be cautioned about operating machinery or driving if affected.
| Other Cardiotoxic Agents (e.g., Trastuzumab, Cyclophosphamide at high doses, other Anthracyclines) | Markedly increased risk of cardiomyopathy and CHF. Sequential use requires careful monitoring and lower cumulative dose limits. | High |
| Cimetidine | Increases plasma concentration of epirubicin by inhibiting hepatic metabolism. Avoid concomitant use. | Moderate |
| Live Vaccines (e.g., MMR, Varicella, Yellow Fever) | Risk of disseminated infection due to immunosuppression. Contraindicated. | High |
| Radiation Therapy | Enhanced toxicity in irradiated fields (recall reaction). Potentiates cardiotoxicity with mediastinal radiation. | Moderate |
| Paclitaxel | If administered before epirubicin, may reduce epirubicin clearance, increasing toxicity. Sequence: Epirubicin before paclitaxel is preferred. | Moderate |
| CYP2D6 Inhibitors (e.g., Fluoxetine, Paroxetine) | Theoretical potential to alter metabolism, though CYP pathway is minor. Clinical significance unclear. | Low |
Same composition (Epirubicin (100mg)), different brands: