L-873724

L-873724 is a potent, orally bioavailable, selective and reversible^[2] non-basic cathepsin K inhibitor, with IC₅₀s of 0.2, 178, 264, and 5239 nM for cathepsin K, cathepsin S, cathepsin L, cathepsin B, respectively^[1]. L-873724 also exhibits an IC₅₀ of 0.5 nM for rabbit cathepsin K. L-873724 inhibits bone resorption^[2]. IC50 & Target: IC50: 0.2 nM (Cathepsin K), 178 nM (Cathepsin S), 264 nM (Cathepsin B), 5239 nM (Cathepsin B)^[1], 0.5 nM (Rabbit cathepsin K)^[2] In Vitro: L-873724 (Compound 22) is a potent and selective non-basic cathepsin K inhibitor, with IC₅₀s of 0.2, 178, 264, and 5239 nM for cathepsin K, cathepsin S, cathepsin L, cathepsin B, respectively. L-873724 also shows IC₅₀s of 95, 1221 and 4807 nM for Ramos cathepsin S, Hep G2 cathepsin L, Hep G2 cathepsin B^[1]. L-873724 exhibits an IC₅₀ of 0.5 nM for rabbit cathepsin K^[2]. In Vivo: L-873724 is orally bioavailable, non-lysosomotropic, and efficacious in the rhesus monkey bone resorption model^[1].