A once-weekly injectable drug, semaglutide, initially developed to treat type 2 diabetes, is showing promise in slowing the progression of osteoarthritis, according to a study published this week in the journal Cell Metabolism. The research, conducted in both mice and a modest group of human participants, suggests the drug may improve cartilage health independent of weight loss, a finding that could broaden its potential therapeutic applications.
Osteoarthritis, a degenerative joint disease affecting millions worldwide, is often linked to excess weight, particularly in weight-bearing joints like the knees and hips. The mechanical stress of carrying extra weight contributes to cartilage breakdown, and obesity is similarly associated with systemic inflammation that can worsen symptoms. Current management strategies typically involve physical therapy, medication, and, in severe cases, surgery.
Semaglutide, a glucagon-like peptide-1 receptor (GLP-1R) agonist, has gained prominence for its effectiveness in promoting weight loss. Approved by the U.S. Food and Drug Administration under the brand names Ozempic and Wegovy, it works by mimicking a natural hormone that regulates appetite and blood sugar. However, the new study indicates semaglutide may have benefits beyond simply reducing body weight.
Researchers found that in an osteoarthritis mouse model, semaglutide reduced pathological changes including cartilage degeneration, osteophyte formation, and synovial lesions. The study pinpointed a mechanism involving the “GLP-1R-AMPK-PFKFB3” axis, suggesting semaglutide reprograms chondrocyte metabolism, shifting it from glycolysis to oxidative phosphorylation, ultimately leading to cartilage restoration. A pilot clinical study (ChiCTR2200066291) provided preliminary support for these findings in humans.
The study’s authors specifically designed their experiments to isolate the effects of semaglutide from those of appetite suppression and weight loss. This was achieved through a precisely controlled diet. The results demonstrated that semaglutide’s chondroprotective effects were present even without significant weight reduction, indicating a direct impact on cartilage health. For every pound of body weight lost, knee pressure is reduced by approximately four pounds, but this study suggests a separate benefit exists.
A separate study, published in the New England Journal of Medicine, is currently evaluating the effects of once-weekly semaglutide injections on individuals with obesity and knee osteoarthritis experiencing moderate-to-severe pain. Initial results indicate significant reductions in body weight among participants, but the full extent of its impact on joint health is still being assessed.
While the findings are encouraging, researchers caution that larger, more comprehensive clinical trials are needed to confirm the benefits of semaglutide for osteoarthritis and to determine optimal dosage and treatment duration. The long-term effects of the drug on cartilage health also remain unknown.
