LIVERPOOL, ENGLAND – At 3 years of follow-up, the cartilage-building effects of sprifermin appear to be sustained, according to further data to be released from the phase 2 FORWARD trial.
The difference from placebo in mean cartilage thickness at the tibiofemoral joint (TFJ) at 3 years was 0.05 mm for a 100-mcg dose of sprifermin given every 6 months (P less than .0001), 0.02 mm for a 100-mcg dose given every 12 months (P = .193), 0.01 mm for a 50-mcg dose given every 6 months (P = .530), and –0.02 mm for a 50-mcg dose given every 12 months (P = .160).
“These data, 18 months after the last active injection, extend the results which we previously presented and assessed at 6 months after the last injection,” study investigator , said at the World Congress on Osteoarthritis.
The prior 2-year findings, which were reported at the annual meeting of the American College of Rheumatology in November 2017, showed statistically significant dose-dependent structural modification in TFJ cartilage. Furthermore, the increase in cartilage thickness was seen in both medial and lateral compartments of the TFJ, and in the central medial subregion of the TFJ.
Sprifermin is one of several drugs currently being investigated as a potential disease-modifying osteoarthritis drug, none of which are currently licensed for use. It is a novel human recombinant version of fibroblast growth factor 18 that has been shown to increase chondrocyte proliferation that results in overall extracellular matrix production and subsequent hyaline-line cartilage formation.
The comprised 549 patients with symptomatic radiographic primary femorotibial knee OA who were aged 40-85 years. For inclusion, patients had to have Kellgren-Lawrence Grade 2 or 3, with a medial minimum joint space width of 2.5 mm or more. In addition, patients had to have a history of OA pain for at least 6 months and either symptoms requiring pain medication or a pain score of 4-9 on the 10-point question 1 of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).
Dr. Hochberg, professor of medicine, epidemiology, and public health and head of the division of rheumatology and clinical immunology at the University of Maryland, Baltimore, noted that the current analysis at 3 years’ follow up had been prespecified and that the plan was to continue follow-up out to 5 years.