INTRODUCTION: Disorders with inactivating mutations of the SOST gene result in 
reduced or absent expression of sclerostin and are associated with high bone 
mass. Sclerostin is an important regulator of bone formation due to its 
inhibitory actions in the osteoanabolic Wnt signaling pathway. Advances in 
understanding the mechanisms of action of this signaling molecule have led to 
the development of a pharmacological inhibitor of sclerostin with potential 
clinical applications as an osteoanabolic drug for the treatment of 
osteoporosis.
AREAS COVERED: Romosozumab is the first humanized monoclonal sclerostin antibody 
to be tested in clinical trials. Similar to preclinical animal studies with 
sclerostin antibodies, initial clinical studies show that romosozumab increases 
bone formation and bone mineral density.
EXPERT OPINION: Blocking sclerostin action with romosozumab is a promising new 
therapeutic approach to osteoanabolic therapy of osteoporosis; efficacy and 
safety data on large controlled studies are awaited.