Cyproterone acetate, testosterone, LH, FSH, and prolactin levels in plasma after intramuscular application of cyproterone acetate in patients with prostatic cancer

Abstract

Five patients with prostatic carcinoma (stages T3N0M0) were injected intramuscularly with 300 mg of cyproterone acetate (CPA) (Androcur-Depot) at weekly intervals. The concentrations of CPA, testosterone, LH, FSH, and prolactin in plasma after the first, third, and fifth injection were measured by specific radioimmunoassays. After five injections of Androcur-Depot, CPA levels were slightly higher than in previous determinations, suggesting that a balance between active substance release from the depot and excretion could be achieved after eight to twelve injections, with only slightly higher levels of active substance attained. Testosterone levels clearly were reduced after the first injection of CPA, but the lowest values were registered only after three injections. Plasma concentrations of FSH and LH were slightly diminished, whereas the prolactin level increased after CPA therapy.

Effect of very high dose D-leucine6-gonadotropin-releasing hormone proethylamide on the hypothalamic-pituitary testicular axis in patients with prostatic cancer.

“…Lower doses of estrogen produce tumor regression without cardiovascular complications but may be less effective than castration. Progestational agents alone are only transiently effective at reducing testosterone (5,6), whereas the recent introduction of antiandrogens (7) or combination of estrogen with progestins shows promise for a sustained reduction of testosterone levels lasting up to 16 mo in one study (8).…”

Investigation of the Combination of the Agonist D-Trp-6-LH-RH and the Antiandrogen Flutamide in the Treatment of Dunning R-3327H Prostate Cancer Model

“…Several antiandrogens have been used clinically for the treatment of prostatic cancer [50,. The progestational agents megestrol acetate and cyproterone acetate have had extensive clinical trials [50,54,55]. Cyproterone acetate acts not only by interfering with the receptor binding and nuclear retention of 5 a-dihydrotestosterone, but also at high doses inhibits the release of gonadotropins [60,61].…”

Clinically established biodegradable long acting injectables: An industry perspective

“…The same dosing (300 mg IM) was as efficient as 50 mg tablets of cyproterone acetate administered orally twice a day in the treatment of hot flush symptom, a hostile symptom associated with antiandrogen therapy in prostatic cancer patients [204]. Similar studies reported that weekly IM injections of Androcur Depot® yielded the same plasma levels of cyproterone acetate as 50 mg tablets orally administered 4 to 8 times a day (200-400 mg/ day) [205,206]. In other words, one injection of Androcur Depot® (300 mg) is only 21% of the minimal oral dose (200 mg × 7 days) required for weekly management of prostatic cancer.…”