Doxil, a pegylated liposomal formulation of doxorubicin HCl, has been shown to be an effective single agent therapy with a manageable side effect profile in patients with metastatic breast cancer, according to a clinical study presented as a poster at the 9th Annual European Cancer Conference.
The phase II multicenter trial, led by Dr. Malcolm Ranson of the Christie Hospital, Manchester, England, enrolled 71 patients with advanced multiple site metastatic breast cancer with poor Karnofsky performance status. Doxil was administered at doses of 45 to 60 mg/m2 every 3 to 4 weeks to define the optimum balance between efficacy and toxicity. Patients had received either no prior chemotherapy or previous therapy with the combination of cyclophosphamide, methotrexate, and fluorouracil (CMF).
An overall response rate of 31% was observed (4 complete responses and 16 partial responses). The duration of response was 9 months. Among the patients who had received prior CMF therapy, an objective response of 32% was observed.
When compared to conventional doxorubicin, nausea, vomiting, and alopecia were notably mild or absent with Doxil. Ninety percent of cycles resulted in grade 2 or less neutropenia. Cutaneous toxicity, manifested as palmar plantar erythrodysesthesia (PPE), was the dose- limiting toxicity observed, and was manageable through dose and schedule modifications. When Doxil was dosed at 45 mg/m2 every 4 weeks, grade 3 and 4 PPE was minimal or absent.
Doxil is a new active agent for the treatment of breast cancer, said Dr. Ranson. The response rate seen with Doxil, and its tolerable safety profile, would favor its use in combination chemotherapy for women with poor prognosis metastatic breast cancer.