Efficacy and safety of sprifermin injection for knee osteoarthritis treatment: a meta-analysis

To perform a meta-analysis comparing the structural progression and clinical symptom outcomes as well as adverse events experienced from intra-articular injections of sprifermin compared to a placebo treatment for patients with knee osteoarthritis (KOA).

We systematically searched the literature for studies that compared long-term outcomes between sprifermin and placebo injections for KOA treatment. Meta-analysis was performed with RevMan5.3 using an inverse variance approach with fixed or random effects models. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.

Eight studies were included. Overall, there was significantly less improvement of WOMAC total scores in patients receiving sprifermin, compared with the placebo (mean difference (MD) = 3.23, 95% CI 0.76-5.69; I² = 0%; P = 0.01). Further, sprifermin injection patients gained more, and lost less, cartilage thickness and volume in total femorotibial joint (cartilage thickness: standardized mean differences (SMD) = 0.55, 95% CI 0.26-0.84; I² = 78%; P = 0.0002; cartilage volume: SMD = 0.39, 95% CI 0.20-0.58; I² = 49%; P < 0.0001). Changes in the cartilage surface morphology of the medial tibio-femoral joint (MD = -0.30, 95% CI -0.44 to -0.16; I² = 0%; P < 0.0001) and patello-femoral joint (MD = -0.22; 95% CI -0.37 to -0.07; I² = 0%; P = 0.004) showed a significant difference between the sprifermin and placebo injections. Moreover, there were no significant differences between sprifermin and the placebo in the risk of treatment-emergent adverse events (OR = 1.05; 95% CI 0.52-2.14; I² = 48%; P = 0.89).

The data from the included studies provide strong evidence to determine the effect of intra-articular sprifermin on joint structure in individuals with KOA and show no specific adverse effects. Nevertheless, intra-articular sprifermin did not likely have any positive effect on symptom alleviation.