Finasteride (MK-906) acetate is a potent and competitive 5α-reductase inhibitor, with an IC50 of 4.2 nM for type II 5α-reductase. Finasteride acetate has approximately a 100-fold greater affinity for type II 5α-reductase enzyme than for the type I enzyme. Finasteride acetate can be used for the research of benign prostatic hyperplasia (BPH) and androgenic alopecia[1][2][3].