European early phase II dose-finding study of droloxifene in advanced breast cancer.

Preliminary results from clinical phase II studies with droloxifene demonstrated efficacy and good tolerability. One hundred ninety-six female, postmenopausal patients with advanced breast cancer were treated with 20, 40, or 100 mg of droloxifene daily. Exclusion criteria were as follows: negative ER/PR status, tamoxifen treatment within the preceding three months, chemotherapy within the preceding three weeks, and performance grade of four. Seventeen percent of the patients treated with 20 mg daily responded to treatment, exhibiting complete or partial responses according to World Health Organization criteria. In the 40-mg group, 30% responded and in the 100-mg group, 31% responded. Adverse symptoms generally were mild.