Well, the article notes that it seemed effective on human tissue samples.

   The researchers also tested cartilage taken from patients undergoing total knee replacement for osteoarthritis. After one week of treatment with the 15-PGDH inhibitor, the tissue showed fewer 15-PGDH-producing chondrocytes, reduced expression of cartilage degradation and fibrocartilage genes, and early signs of articular cartilage regeneration.

So, IMO that shows hope for once it goes to trials.