[Clinical evaluation of CGS16949A in advanced or recurrent breast cancer--a multi-institutional late phase II clinical trial].

A multi-institutional late-phase II clinical trial of CGS 16949A was conducted at the dose of 1 mg twice daily in postmenopausal patients with advanced or recurrent breast cancer. Seventy patients entered into the study; 65 were eligible and 53 were complete cases. There were 3 CR, 11 PR, 10 long-NC, 14 NC and 25 PD with an overall response rate of 22.2% in 63 evaluable cases. The median period of overall duration of responses was 327.5 days. There were 22 cases that drug was found useful or better, and global usefulness rate was 33.8%. Forty six (76.7%) of patients experienced no side effects in this therapy. Grade 2 toxicities included anorexia (1 pt.), feeling of distension of abdomen (1 pt.), vomiting (1 pt.), fatigue (1 pt.), and only one patient experienced Grade 3 toxicity (anorexia). Grade 2 laboratory abnormalities were confirmed in two patients; one with elevated gamma-GTP and another with elevated LDH, and both were in the absence of liver metastasis. From these results, it is concluded that CGS16949A seemed to be a useful hormonal agent in the treatment of postmenopausal breast cancer.