finrozole

Finrozole (research code: MPV-2213ad) is a nonsteroidal, orally active, small-molecule competitive inhibitor of aromatase (CYP19A1), the enzyme responsible for converting androgens to estrogens. By blocking aromatase, it reduces estrogen biosynthesis. Initially developed by Orion and Hormos Medical (later acquired by QuatRx Pharmaceuticals), finrozole was evaluated in Phase II clinical trials for human indications, including lower urinary tract symptoms associated with a reduced androgen/estrogen ratio in aging males (e.g., benign prostatic conditions), metastatic breast cancer, and Crohn's disease, all of which were subsequently discontinued. However, the drug was successfully repurposed for veterinary medicine by Vetcare and received European marketing authorization in April 2025 under the brand name Prevestrus vet. In veterinary applications, it is indicated for the reproductive management of female dogs to control estrus, alleviate signs of heat, and reduce the risk of pregnancy.

Brand names

LystralinPrevestrusPrevestrus vet

Other names

4-[(1R,2S)-3-(4-fluorophenyl)-2-hydroxy-1-(1H-1,2,4-triazol-1-yl)propyl]benzonitrile4-[3-(4-fluorophenyl)-2-hydroxy-1-(1,2,4-triazol-1-yl)-propyl]benzonitrileCAS 160146-17-8CAS160146-17-8CAS-160146-17-8