Fasinumab for osteoarthritis: a systematic review and meta-analysis of efficacy and safety

Objective Fasinumab, a newly developed anti-nerve growth factor monoclonal antibody, has been evaluated in clinical trials for its potential to alleviate symptoms in osteoarthritis patients. This meta-analysis evaluates the efficacy and safety of different Fasinumab dosages compared with placebo in patients with osteoarthritis. Methods PubMed (MEDLINE), Cochrane CENTRAL, ClinicalTrials.gov, and Google Scholar were searched for double-blinded RCTs comparing Fasinumab with placebo till December 2025. Primary outcomes were WOMAC pain, WOMAC function, and Patient Global Assessment (PGA) scores. Secondary outcomes included safety profile such as Adjudicated Arthropathy, Adverse events, serious adverse events, all-cause mortality. Cochrane Risk of Bias 2 was used for quality assessment. A random effects model was used for analysis, with subgrouping by dosage. Results Six RCTs, involving 9,429 participants, were included. All trials included had a low risk of bias. At 16 weeks, 1 mg Subcutaneous (SC) Every four weeks (Q4W), 1 mg SC Every eight weeks (Q8W), and 3 mg SC Q4W showed a greater statistically significant reduction in WOMAC pain and function scores compared to placebo. However, according to minimal clinically important differences (MCIDs), only 1 mg SC Q4W and 3 mg SC Q4W may provide clinically meaningful reductions in WOMAC pain ([MD: -1.05, (95% C.I. -1.32 to -0.78), p < 0.00001, I²=28%] and [MD: -1.16, (95% C.I. -1.58 to -0.75), p < 0.00001, I²=0%], respectively) and function scores ([-1.05 (95% C.I. -1.32 to -0.79), p < 0.00001, I²=20%] and [MD: -1.24, (95% C.I. -1.65 to -0.83), p < 0.00001, I²=0%], respectively) more than placebo; however, the confidence intervals include effects smaller than the MCID threshold, limiting certainty regarding clinically meaningful benefit. A 1 mg SC Q4W dosage regimen is favored over a placebo in improving PGA scores at 16 weeks. Further, Fasinumab use may increase the risk of adverse events, including Joint-replacement surgery and Adjudicated Arthropathy. Conclusion Although select fasinumab regimens demonstrated statistically significant reductions in WOMAC pain, function, and PGA scores at 16 weeks, confidence interval overlaps with conservative MCID thresholds limit certainty regarding clinically meaningful efficacy. Additionally, treatment may carry increased risks, including adjudicated arthropathy.In addition, osteoarthritis is a chronic disease, and these short-term efficacy outcomes may not reflect long-term treatment effectiveness. These findings are based on trials assessed as having an overall low risk of bias. Further research is needed to confirm these findings.