panomifene and Breast-Neoplasms

Influence of a new Hungarian antiestrogen, panomifene (PAN) was investigated on some hormone levels of 10 postmenopausal healthy women during a partially double-blind placebo controlled phase I/a study. Following a single oral administration of PAN serum estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin (PROL) levels were measured by RIA at two selected dose levels: 12 mg and 120 mg. The low dose (12 mg) results in an increased E2 level in some cases probably due to the intrinsic estrogenic (agonistic) character of the drug. The high dose (120 mg) seems to have a strong antiestrogenic (antagonistic) action. FSH and LH changed within the normal postmenopausal range at both doses, PROL slightly decreased at 12 mg dose level. During the 14-day follow up, the 120 mg PAN considerably suppressed the PROL secretion proving the antiestrogenic character of the "high" dose. PAN seems to be a safe tamoxifen analogue, the single oral dose of which does not exert any noteworthy (pathogenic) side effect on some hormone levels of healthy women.

Topics: Breast Neoplasms; Double-Blind Method; Drug Evaluation; Estrogen Antagonists; Female; Humans; Menopause; Middle Aged; Palliative Care; Placebos; Postmenopause; Tamoxifen

The aim of the study was to find new antiestrogenic and antiandrogenic structures. Out of the triphenyl-alkene derivatives Panomifene (EGIS-5660) proved to be the most active antiestrogenic compound which binds to specific estrogen receptors and exhibits inhibitory effects on experimental mammary tumors both in vitro and in vivo. The investigated antiandrogenic compounds were indol and imidazole derivatives. One of these compounds a di-imidazolil derivative, GYK1-24479 inhibited the in vitro androgen (testosterone and androstenedione) biosynthesis both in vitro and in vivo in concentration/dose dependent manner, and in these respects proved to be more active than the referent ketoconazole.

Topics: Androgen Antagonists; Androgens; Animals; Antineoplastic Agents, Hormonal; Breast Neoplasms; Corticosterone; Estrogen Antagonists; Female; Humans; Imidazoles; In Vitro Techniques; Mammary Neoplasms, Experimental; Rats; Receptors, Estrogen; Tamoxifen; Tumor Cells, Cultured