FDA Approves the First Surrogate Endpoint in Osteoporosis Clinical Trials

The U.S. Food and Drug Administration (FDA) has qualified image-based bone mineral density (BMD) biomarkers as a surrogate endpoint for fractures in clinical trials of osteoporosis therapies, marking an important advance in drug development. This milestone resulted from the Study to Advance BMD as a Regulatory Endpoint (SABRE), a multi-sector collaboration initiated by the American Society for Bone and Mineral Research (ASBMR) and the Foundation for the National Institutes of Health (FNIH) Biomarkers Consortium, and led by ASBMR experts Dennis Black, PhD, Mary Bouxsein, PhD, and Richard Eastell, MD. ASBMR provided financial and institutional support through sustained public–private partnerships, with ongoing leadership from multiple ASBMR Councils and presidents, most recently Drs. Peter Ebeling, Mary Bouxsein, Laura Calvi, and Jennifer Westendorf.

Historically, FDA approval of osteoporosis therapies has relied on fracture outcomes, which are relatively infrequent events and therefore require large, lengthy, and costly clinical trials, limiting innovation—particularly for novel or combination treatments. By qualifying image-based BMD as a surrogate endpoint, the FDA formally recognizes that BMD improvements reliably predict fracture risk reduction, enabling smaller and shorter trials, lowering development costs, accelerating patient access to new therapies (including anabolic and sequential approaches), and facilitating studies in high-risk or niche populations where fracture endpoints are impractical. Clinically, this decision validates long-standing practice that BMD is a meaningful marker of treatment benefit, and strategically, it aligns osteoporosis with other fields that use biologically sound surrogate endpoints to drive progress, with the potential to substantially reduce the current treatment gap.

To learn more, watch this video by ASBMR where Dr. Black and Dr. Bouxsein further discuss the impact of this decision.