Effects of Sprifermin on symptoms and structure in knee oste
A cross-sectional study was performed to assess pain outcomes and cartilage thickness change in a subgroup at risk (SAR) of further progression in the FORWARD trial of knee osteoarthritis patients treated with sprifermin.

Patients were randomised 1:1:1:1:1 to: sprifermin 100 microg every 6 months (q6mo), 100 microg q12mo, 30 microg q6mo, 30 microg q12mo, or placebo for 18 months. SAR was defined as baseline medial or lateral minimum joint-space width (mJSW) 1.5–3.5 mm and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score 40–90 units. Follow-up to 3 years was included in the analysis. Treatment benefit was explored by repeated measures, linear dose-effect trends by timepoint.

--The SAR comprised 161 of 549 patients. Mean difference in WOMAC pain at year 3 for sprifermin 100 microg q6mo vs placebo SAR was -8.75 (-22.42, 4.92) for SAR vs 0.97 (-6.22, 8.16) for the intent-to-treat population.

--SAR placebo patients lost more cartilage over 2 years than the modified ITT (mITT) placebo arm (mean change from baseline, mm [SD]: -0.05 vs -0.02).

--Net total femorotibial joint thickness gain with sprifermin 100 microg q6mo was similar in the SAR and in the mITT group: 0.06 vs 0.05.

To summarize, choosing a patient with a low mJSW and moderate-to-high pain at the outset resulted in faster disease progression and showed that structure change (with a net effect on total cartilage thickness) translated into symptomatic benefit.

Source: https://www.sciencedirect.com/science/article/pii/S0049017221000354