Dutasteride-13C6

Dutasteride-13C6 is intended for use as an internal standard for the quantification of dutasteride by GC- or LC-MS. Dutasteride is a dual inhibitor of 5α-reductase types I and II (Kis = 6 and 7 nM, respectively). Its inhibition is time-dependent with apparent Ki values of 17 and 4.3 nM at 10- and 30-minute reaction times, respectively. Dutasteride decreases prostate weight in a rat model of benign prostatic hypertrophy induced by testosterone after castration when administered daily for 28 days at doses of 0.045 mg/kg as a solution or 0.756 mg/kg in subcutaneous microspheres. It also decreases prostate weight in large probasin-large T antigen mice, a transgenic model of prostate cancer. Formulations containing dutasteride have been used in the treatment of benign prostatic hyperplasia.