KDH-136

KDH-136 is a small molecule cathepsin K inhibitor developed by Kowa Dental Health for the treatment of periodontitis. Cathepsin K is a lysosomal cysteine protease that plays a critical role in bone resorption by degrading type I collagen, the primary protein component of the bone matrix. In the context of periodontitis, overactivity of cathepsin K in osteoclasts leads to the destruction of alveolar bone supporting the teeth. KDH-136 is designed to be applied locally as a dental ointment into the periodontal pocket to inhibit bone loss and promote the stabilization of dental structures. While it reached Phase 2 clinical trials in Japan, development appears to have been discontinued as it is no longer listed in the developer's active pipeline.