Bone quality: a perspective from the Food and Drug Administration.

Osteoporosis, a disease of compromised bone strength, is a leading cause of fracture, morbidity, and mortality. The past 10 years have resulted in the development of new pharmacologic therapies for the treatment of this disease. Most of these agents have been approved for the treatment of osteoporosis based on placebo-controlled fracture trials. However, recent ethical concerns regarding placebo-controlled trials threaten to derail the development of new, possibly better, treatment options. Novel noninvasive imaging technologies may offer greater insight into the pathophysiology and biomechanics of osteoporosis and fracture. Because of these advances, many hope to find a new biomarker that will predict fracture risk better than the current bone density measurements and that ultimately will replace fracture as the primary endpoint for osteoporosis drug registration trials. This paper discusses the perspective of a Food and Drug Administration reviewer regarding the role of surrogate markers as they relate to the quest for new, safe and efficacious treatments for osteoporosis.