New anabolic therapies in osteoporosis.
Anabolic agents represent an important new advance in the therapy of osteoporosis. Their potential might be substantially greater than the anti-resorptives. Because the anti-resorptives and anabolic agents work by completely distinct mechanisms of action, it is possible that the combination of agents could be significantly more potent than either agent alone. Recent evidence suggests that a plateau in BMD might occur after prolonged exposure to PTH. Anti-resorptive therapy during or after anabolic therapy might prevent this skeletal adaptation. Protocols to consider anabolic agents as intermittent recycling therapy would be of interest. Of all the anabolics, PTH is the most promising. However, there are unanswered questions about PTH. More studies are needed to document an anabolic effect on cortical bone. More large-scale studies are needed to further determine the reduction in nonvertebral fractures with PTH, especially at the hip. In the future, PTH is likely to be modified for easier and more targeted delivery. Oral or transdermal delivery systems may become available. Recently, Gowen et al have described an oral calcilytic molecule that antagonizes the parathyroid cell calcium receptor, thus stimulating the endogenous release of PTH. This approach could represent a novel endogenous delivery system for intermittent PTH administration. Rising expectations that anabolic therapies for osteoporosis will soon play a major role in treating this disease are likely to fuel further studies and the development of even more novel approaches to therapy.
Rubin
Mishaela R
MR
Department of Medicine, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA.
Bilezikian
John P
JP
D000368:Aged; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects*; D005260:Female; D005459:Fluorides / Q000627:therapeutic use; D013006:Growth Hormone / Q000627:therapeutic use; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D007334:Insulin-Like Growth Factor I / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009652:Norpregnenes / Q000627:therapeutic use; D010024:Osteoporosis / Q000188:drug therapy* / Q000503:physiopathology; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy; D010281:Parathyroid Hormone / Q000627:therapeutic use; D013324:Strontium / Q000627:therapeutic use
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D009652:Norpregnenes; D010281:Parathyroid Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; C027385:tibolone; D005459:Fluorides; D013324:Strontium