BGS-649 (leflutrozole) is a novel once weekly oral aromatase inhibitor being developed as a first-line therapy for the treatment of obese men with hypogonadotropic hypogonadism (HH).


Hypogonadotropic Hypogonadism (HH)-100.jpg Hypogonadotropic Hypogonadism (HH) - mobile-100.jpg Hypogonadotropic Hypogonadism (HH) - mobile-100.jpg

HH is a clinical syndrome that results from inadequate levels of testosterone, and can cause increased obesity, cardiovascular disease, hypertension, insulin resistance, type 2 diabetes, depression, osteoporosis, and infertility. In the obese, the decrease in testosterone is driven by high levels of the aromatase enzyme in the fat tissue. The aim is to use BGS-649 to normalise testosterone levels and improve the related conditions.

View Bgs-649 poster


  1. Based on 2016 WHO estimates
  2. Hofstra et al (2008) Netherlands J. Med, 66 p103-109
  3. Update on Hypogonadism and Testosterone Replacement Therapy (2011) Chapter in Practicing Clinical Exchange p1-15


View clinical studies