Phase III randomized trial of toremifene vs tamoxifen in hormonodependant advanced breast cancer.

Abstract

Efficacy and safety of toremifene (TOR) 60 mgs/dayly/o.r. was compared with tamoxifen (TAM) 40 mgs/dayly/o.r. in a group of postmenopausal women with advanced breast cancer, without previous systemic therapy for advanced breast cancer. The study was a prospective double-blind randomized trial. All treated patients presented with positive estrogen receptors. Main end points were response rates, toxicity profile analysis, time to progression and survival. WHO and ECOG criteria were employed for response evaluation while toxicity was assesed according to WHO guidelines. Curves were constructed by means of Kaplan-Meier methodology and were compared by means of log-rank test. From January 1996 to January 1999 a total of 217 patients were included in the study (106 in the TOR branch and 111 in the TAM arm). Both groups of patients were homogeneous regarding the main prognostic factors. A response rate of 64% (68/106) was observed in the TOR group as compared with a 52% (58/111) in the TAM group. Median times to progression and overall survival were not significantly different. A lower incidence of undesirable effects was apreciated in the TOR arm. Our data suggest that TOR is an efficient and well-tolerated agent for the therapy of postmenopausal women with hormonal positive receptors advanced breast cancer, and must be considered an alternative to TAM as first line therapy for ER+ advanced breast cancer patients and as well as an adjuvant treatment.