Abstract :
The new generation of aromatase inhibitors represent convenient and well-tolerated treatments for advanced breast cancer in postmenopausal women. With the exception of fadrozole, the others, anastrozole, letrozole and vorozole are given once daily by oral administration and are highly selective for the aromatase enzyme. Phase 11 studies have demonstrated the clinical activity of these agents. The comparative studies involving anastrozole and megestrol acetate, have shown that the new generation aromatase inhibitors, as typified by anastrozole, are as effective as the standard second-line agent megestrol acetate, in the treatment of advanced breast cancer in postmenopausal women. Furthermore, the improved tolerability of anastrozole, particularly with respect to weight gain, provides a valuable alternative in the treatment of advanced breast cancer patients failing on tamoxifen. Promising results have been observed in the study comparing fadrozole and tamoxifen as first-line treatment for advanced disease, where no significant differences in efficacy or toxicity was observed. Further studies are, however, required before the new generation of aromatase inhibitors can be used in this setting. The good tolerability of these agents, coupled with the clinical activity seen to date, make the new generation of aromatase inhibitors excellent candidates for investigation in the adjuvant setting. Such studies are planned, and an anastrozole adjuvant study is due to be initiated during 1996.
