A randomised study of CGS 16949A (fadrozole) versus tamoxifen in previously untreated postmenopausal patients with metastatic breast cancer

BACKGROUND:: Fadrozole, a potent, highly specific inhibitor of aromataseactivity, has only been used as second-line therapy in treatmentof post-menopausal women with advanced breast cancer. A prospectivelyrandomised study was therefore undertaken to compare relativeclinical efficacy of fadrozole as first-line treatment to thatof tarnoxifen. PATIENTS AND METHODS:: Eighty postmenopausal women who had not received prior treatmentfor advanced/metastatic breast cancer were randomised to receiveeither fadrozole, 1 mg twice daily, or tamoxifen, 20 mg daily. RESULTS:: Toxicity was not statistically different on the two treatmentarms. Only mild to moderate toxicity was documented: hot flashesin 37%, headaches in 6.5%, mild fatigue in 2.6%. There werealso no statistically significant differences in objective responserates, survival or time to treatment failure (TTF). Objectiveresponse rate on fadrozole was 50% (complete response (CR) 8.3%and partial response (PR) 42%). On tamoxifen objective responsewas 44.7% (CR 21% and PR 24%). Median TTF was 4.9 months onfadrozole and 5 months on tamoxifen. Median survival was 22.7months on fadrozole and 27.5 months on tamoxifen. CONCLUSION:: While response rates, survival and TTF were not statisticallysignificantly different, there were more complete responseson tamoxifen and duration of objective response (CR + PR) wassignificantly longer in the patients treated with tamoxifen. breast cancer, fadrozole, postmenopausal, tamoxifen