Following on from my recent blog post on emerging treatments in osteoporosis, one of new approaches in development is the inhibition of cathepsin-K.

Chemical Structure of odanacatib MK 0822. Image Copyright Merck 300x148 Mercks cathepsin K inhibitor odanacatib in osteoporosis

Cathepsin-K inhibition is a novel approach to osteoporosis treatment and Merck’s odanacatib is leading the way in this new class of drugs. It is currently in phase III development, with 16,716 subjects enrolled (NCT00529373).

Cathepsins are lysosomal proteases. Cathepsin K (Cat-K) is a cysteine protease that plays an important role in the function of osteoclasts (the cells responsible for bone destruction). Cat-K acts to degrade bone collagen. By inhibiting it, the removal of bone matrix proteins by osteoclasts is reduced.