[Fundamental and clinical study of the anti-prostatic effect of allylestrenol]

The anti-androgen activity of allylestrenol was studied in the rat, and it was found to have an activity which was equivalent to that of chlormadinone acetate. The direct anti-prostatic activity is the result of the following mechanism: inhibition of serum testosterone uptake into the prostate, inhibition of testosterone-5 alpha-reductase activity and inhibition of 5 alpha-DHT . receptor complex formation. Large doses of allylestrenol administered to normal mature rats, inhibit the hypothalamus-pituitary-gonadal axis, and atrophy of the prostate will be more marked due to an indirect effect as a result of the reduction in the serum testosterone level. Based on this finding, we performed a clinical trial with allylestrenol in patients with hypertrophy of the prostate and cancer of the prostate. We administered 45 mg a day allylestrenol to 19 patients with prostatic hypertrophy and obtained satisfactory clinical results in so far as improvement of micturition and reduction in prostate mass was concerned. We also administered 90 mg a day of allylestrenol to 4 patients with cancer of the prostate and obtained a cytostatic effect.