Anabolic Agents for Osteoporosis Reviewed

We are now on the verge of seeing a new class of ‘anabolics’ for osteoporosis with the potential to rebuild bone loss, comment the authors of recent review in the New England Journal of Medicine.

Introducing their review Dr Ernesto Canalis and colleagues highlight the worldwide health burden of osteoporosis, believed to affect between 5 and 8 million adults in the United States alone. The authors note that as well as antiresorptive therapies, anabolic agents also present opportunities in managing this condition.The paper reviews mechanisms by which anabolic agents stimulate bone formation at the cellular, biochemical, and molecular levels together with other aspects of ongoing research.Focusing on polypeptide anabolic agents and strontium ranelate Canalis’s group discuss signals that regulate bone formation, the clinical relevance of anabolic signalling molecules and other candidate molecules. These novel candidate molecules include antagonists of Dkk-1, soluble activin receptors and osteoblast proteasome and its inhibitors. The authors note that whilst parathyroid hormone is the only prototypical anabolic agent available at this time, other agents may be developed. With these new developments based on our recent understanding of anabolic pathways and intermediate molecules such as bone morphogenetic proteins, Wnt, and IGF-I and their regulatory molecules.”Although the systemic administration of anabolic agents constitutes a promising therapeutic approach, the modification of anabolic signals specifically within bone may become another new avenue for the treatment of osteoporosis,” the group add.(Source : Canalis E, Giustina A, Bilezikian J. “Mechanisms of Anabolic Therapies for Osteoporosis.” New England Journal of Medicine. 2007; 357: 905-16. : sanofi-aventis : September 2007)