Atrimustine [bestrabucil, busramustine, KM 2210, kregan], a conjugate of estradiol and chlorambucil, is a DNA antagonist that was developed by Kureha Corporation (Japan). Atrimustine is an antineoplastic drug that was used for the treatment of breast cancer, non-Hodgkin's lymphoma, as well as Graft-versus-host disease. Side effects of atrimustine in clinical trials included vaginal bleeding and gynecomastia. Atrimustine reached preregistration in Japan for the treatment of cancer, however, its development has been discontinued.

Alfatradiol (17a-estradiol, Ell-Cranell® alpha) is a stereoisomer of the female hormone 17b-estradiol. It inhibits the conversion of testosterone to the metabolite dihydrotestosterone (DHT) by suppressing 5a-reductase activity. In addition, by inhibiting 17b-dehydrogenase, it impedes the conversion process of androstenedione to testosterone, resulting in a reduction in the syntheses of testosterone and DHT. It also accelerates the conversion of testosterone to estradiol by stimulating aromatase, decreasing the level of testosterone and leading to a reduction in DHT. In addition, alfatradiol (17a-estradiol) has been reported to stimulate the generation of hair follicular matrix cells.