Scientists at Novartis AG have discovered a compound that spurred cartilage growth from stem cells to fix damaged joints of mice, a finding that may point to a novel therapy for the arthritis that afflicts most elderly.

Researchers tested 22,000 drug-like molecules using a robotic screen, applying each one to bone marrow stem cells in tiny laboratory dishes. One compound, dubbed kartogenin, promoted the development of chondrocytes, cells that become cartilage, according to the report in the journal Science.

Researchers injected kartogenin into the damaged knee joints of mice, which prompted cartilage regeneration, improved symptoms and lowered levels of proteins and collagen fragments linked to damaged joints. The results suggest a unique, though early-stage, way to regulate cartilage and possibly repair some of the damage from osteoarthritis, the breakdown of cartilage that leads to joint failure, the researchers said.