Value Propositions

A new shot literally regrows knee cartilage. Researchers at Stanford Medicine have identified a novel strategy to regenerate articular cartilage in knees and potentially prevent or treat osteoarthritis (OA). The method targets 15-hydroxyprostaglandin dehydrogenase (15-PGDH), an age-related enzyme—or "gerozyme"—that accumulates in aging tissues and drives degeneration. In aged mice, small-molecule inhibitors of 15-PGDH, delivered systemically or via intra-articular injection, promoted cartilage thickening and regeneration of functional hyaline articular cartilage. This occurred without recruiting stem or progenitor cells; instead, existing chondrocytes underwent transcriptional reprogramming to a youthful state, with reduced populations of inflammatory and hypertrophic/degradative cells and expanded matrix-producing articular chondrocytes. The inhibitors also reversed natural age-related cartilage thinning, improved joint function, and—when administered after simulated ACL injuries—strongly mitigated post-traumatic OA progression and associated pain. Human OA cartilage explants from total knee replacements responded similarly in vitro, showing decreased degradation markers and evidence of new articular cartilage formation. Given that an oral 15-PGDH inhibitor has already completed Phase 1 safety trials for age-related muscle atrophy, the findings open a path toward disease-modifying, regenerative therapies that could delay or obviate the need for joint replacement surgery. [Agarwal, P., Su, S., Ancel, S., et al. (2025). Inhibition of 15-hydroxy prostaglandin dehydrogenase promotes cartilage regeneration. Science. DOI: 10.1126/science.adx6649]