[Long-term clinical study on TAP-144-SR, an LH-RH agonist depot formulation, in premenopausal patients with advanced or recurrent breast cancer. TAP-144-SR Breast Cancer Study Group].

Efficacy and safety of long-term treatment with an LH-RH agonist, TAP-144-SR were studied in premenopausal patients with advanced or recurrent breast cancer. The drug was given sc every 4 week at the dose of 3.75 or 7.5mg. The best objective response rates were 37.0% (17/46) in 3.75mg group, 30.6% (15/49) in 7.5mg group, respectively. The median duration of 12 PR patients in 3.75mg group was 280 (range: 84-830+) days. Serum estradiol level was maintained at < 30pg/ml in most patients given 3.75mg or 7.5mg as scheduled. There was no adverse reactions specific to the longterm administration subsequent to the foregoing 12-week administration study in both dose groups. In conclusion, TAP-144-SR is expected to be one of the first line therapies for patients with premenopausal breast cancer.