Abstract :
The anthracyclines, broad-spectrum anticancer drugs, are the mainstay of chemotherapy regimens. Doxorubicin and epirubicin are most frequently used in the treatment of breast cancer, although toxicities, particularly cumulative cardiotoxicity, limitthe lifetime exposure to these agents. Doxorubicin is widely recognized as the gold standard anthracycline, yet epirubicin is associated with significantly less cardiotoxicity. However, this may be at the expense of potency and doses of epirubicin in the region of 1.5 times that of doxorubicin are required for similar effect. The cardioprotectant dexrazoxane had been shownto reduce anthracycline-induced cardiotoxicity, but at the expense of increased myelotoxicity. New methods of drug delivery have been employed to reduce the cardiotoxicity of doxorubicin. Myocet™ (liposomal doxorubicin) and Caelyx® (pegylated liposomal doxorubicin) are two formulations of liposomal doxorubicin designed to preserve the antitumour effects of doxorubicin but with reduced cardiotoxicity. Caelyx, due to its pegylation, has high affinity for the skin and a very long circulation time. It is indicated for AIDS-related Kaposiʹs sarcoma and metastatic ovarian cancer that is refractory to both paclitaxel-and platinum-based chemotherapy regimens. However, Caelyx is associated with severely limiting palmar-plantar erythrodysesthesia. Myocet has proven efficacy in metastatic breast cancer equalto that of doxorubicin and with reduced cardiotoxicity, thus meeting a previously unmetneed in the management of breast cancer.
