Turosteride (FCE-26,073) is a selective inhibitor of the enzyme 5α-reductase which was under investigation by GlaxoSmithKline for the treatment of benign prostatic hyperplasia (BPH), but was never marketed. Similarly to finasteride, turosteride is selective for the type II isoform of 5α-redcutase, with about 15-fold selectivity for it over type ...