The U.S. Food and Drug Administration (FDA) has cleared the use of bone scan measurements as endpoints in clinical trials -- a move that has major implications for the development of new drugs for treating osteoporosis.
The “landmark” decision will now enable trials to determine if a drug is effective based on bone mineral density (BMD) changes measured by dual-energy x-ray absorptiometry (DEXA) rather than whether the drug prevents fractures, expert Mary Bouxsein, PhD, of Harvard Medical School in Cambridge, MA, explained to AuntMinnie. Bouxsein is an orthopedic surgeon at Beth Israel Deaconess Medical Center in Boston.
She and colleague Dennis Black, PhD, an epidemiologist and biostatistician at the University of California, San Francisco, were principal investigators of the study that generated the evidence that led to the FDA ruling.
Launched through the Foundation for the National Institutes of Health’s Biomarkers Consortium, the study began in 2013 and involved analyzing data from 52 clinical trials with more than 160,000 participants, one of the largest efforts of its kind in osteoporosis research.
Previously, the FDA required trials of new osteoporosis drugs to show that new treatments for osteoporosis can reduce fractures, but this required trials with up to 15,000 patients and waiting up to four years to track whether patients experience fewer fractures. Thus, the expense and time involved essentially discouraged companies from developing new treatments, Black explained.
“It became just not feasible for drug companies at that point to develop new therapies,” he said.
Now, using BMD as an endpoint in phase III trials, researchers will be able to determine whether new drugs are effective based on a percentage change from baseline at 24 months in total hip BMD, and the FDA ruling is expected to rekindle interest in developing new osteoporosis treatments.
The change is also a big win for DEXA scans as a diagnostic tool, further validating a gold-standard technique for diagnosing the disease, Bouxsein added.
The FDA announced that it qualified BMD as a surrogate endpoint to support clinical trials in a news release posted on December 19, 2025.
“The FDA sent us a nice Christmas present,” Black said.
