Regression of Prostatic Hypertrophy by Osaterone Acetate in Dogs.

Abstract

The prostatic regression effect of oral administration of a new steroidal anti-androgen, osaterone acetate, was investigated in dogs with prostatic hypertrophy. To dogs with prostatic hypertrophy, 0.1-1.0 mg/kg of osaterone acetate was orally administered for one week, and the regression rate was observed. It was shown that administration of osaterone acetate at 0.2 mg/kg or higher, sharply regressed prostatic hypertrophy during the early stage. Therefore, this agent may be clinically applicable as a therapeutic agent for benign prostatic hypertrophy.

Effect of Osaterone Acetate Administration on Prostatic Regression Rate, Peripheral Blood Hormone Levels and Semen Quality in Dogs with Benign Prostatic Hypertrophy.

“…Tsumagari et al [14] treated BPH dogs with OSA and showed that the effect persisted for 12 months or longer, emphasizing its superiority over CMA. However, they did not clarify the degree of prostatic regression or duration of persistance [14,15].…”

“…Therefore, in this study, we clarified the duration of inhibition of prostatic hypertrophy by OSA using dogs that met the conditions of prostatic hypertrophy proposed by Wheaton et al [15], and investigated the possibility of OSA for clinical application. The prostatic regression by OSA administration was also investigated by comparison with that in orchidectomized dogs.…”

“…Therefore, to inhibit BPH for a prolonged period, concurrent use of a CMA implant in addition to oral CMA administration may be recommended [6,12]. It has been shown recently that osaterone acetate (OSA), which is being developed as a therapeutic drug for canine BPH, inhibits BPH better than CMA [3,15]. To dogs with BPH, 0.1, 0.2, 0.5, 1.0 mg/kg of OSA was orally administered for one week, and the regression rate was observed.…”

“…To dogs with BPH, 0.1, 0.2, 0.5, 1.0 mg/kg of OSA was orally administered for one week, and the regression rate was observed. It was shown that administration of OSA at 0.2 mg/kg or higher caused marked regression of BPH during the early stage, however, the size of the prostate was evaluated by the area obtained from lateral images of X-ray radiography, not be volume [15]. Tsumagari et al [14] treated BPH dogs with OSA and showed that the effect persisted for 12 months or longer, emphasizing its superiority over CMA.…”

“…The semen volume was maintained at about 10 ml for four months after administration, then increased to [15][16][17][18][19][20] ml. The sperm count varied greatly among days of semen collection, but was within a range of 2-4 × 10 6 .…”