LGD-4033
A selective androgen receptor modulator developed for muscle-wasting conditions, widely used off-label for muscle growth despite documented hepatotoxicity and endocrine suppression.
A Phase I clinical trial demonstrated dose-dependent increases in lean body mass with LGD-4033 at doses of 0.1-1mg over 21 days, with a half-life of approximately 24-36 hours. A case report of 10mg daily for 5 weeks showed increased body mass and lean mass but also significant suppression of total and free testosterone, elevated liver enzymes, worsened lipid profiles, and decreased bone mineral density. Multiple case reports document drug-induced liver injury (DILI) including cholestatic hepatitis with fibrosis. Anti-doping studies have identified numerous metabolites detectable in urine for up to 21 days post-administration. Evidence is limited to small clinical trials, case reports, and anti-doping metabolism studies; no large-scale human safety trials exist.