Phase II trial of vinorelbine/doxorubicin as first-line therapy of advanced breast cancer.

PURPOSE

The study investigated the therapeutic effects of a combination of Navelbine (vinorelbine or 5'noranhydrovinblastine; Pierre Fabre Médicament, Boulogne, France) and doxorubicin in women who had received no prior chemotherapy for locally advanced or metastatic breast cancer.

PATIENTS AND METHODS

Ninety-seven patients with progressive and assessable advanced or metastatic breast cancer who had received no prior chemotherapy except in an adjuvant setting were entered onto the study. Eighty-nine patients were assessable for toxicity and response by World Health Organization (WHO) criteria; the other eight patients were excluded because they did not meet entry criteria or because of protocol violations. Navelbine was administered at 25 mg/m2 by 30-minute intravenous (IV) infusion on days 1 and 8, and doxorubicin at 50 mg/m2 by slow IV infusion on day 1, with each course repeated at 3-week intervals. Patients were treated for a maximum of 11 cycles or until progression or major toxicity.

RESULTS

Objective responses were observed in 66 of 89 assessable patients (74%; 95% confidence interval, 63% to 85%). There were nineteen (21%) complete responses (CRs) and 47 (53%) partial responses (PRs). In addition, 20 patients (22.5%) had stable disease and three (3.5%) progressed while on treatment. Responses were observed at all sites of metastatic disease. Forty-one of 58 patients with visceral disease responded (71%) and 25 of 31 with soft tissue and bone disease experienced an objective response (81%). The median duration of response was 12 months (range, 2.4 to 40.5), and the median overall survival was 27.5 months (range, 4 to 46). Neutropenia was dose-limiting, with 36 patients (41%) experiencing grade 3 or 4 toxicity. Of 727 cycles administered, there were 20 admissions (3%) for treatment of febrile neutropenia, involving 14 of 89 patients (16%). Treatment-related cardiotoxicity at grade 2 to 4 was experienced by 10% of patients and necessitated the interruption of treatment in 1.5% of cycles. Other side effects were uncommon or manageable by conventional means.

CONCLUSION

The encouraging response rates and duration achieved with this combination of Navelbine/doxorubicin under the conditions of this study deserve further randomized comparative trials with standard regimens.