Sprifermin was also tested in a clinical trial for the treatment of osteoarthritis of the knee (The FORWARD (FGF-18 Osteoarthritis Randomized Trial with Administration of Repeated Doses) [15–17], in which suggested that repeated doses of Sprifermin increases cartilage thickness, and reduces cartilage loss over 3.5 years post-treatment. Here, FGF18 is linked to osteoarthritis.