Fasinumab significantly improves pain scores among difficult-to-treat patients of OA of knee or hip: study

Osteoarthritis (OA) causes significant musculoskeletal pain. The study by DiMartino et al assessed the efficacy and safety of fasinumab, an investigational nerve growth factor inhibitor, in patients with moderate-to-severe OA pain of the knee/hip.

In this Phase 3, randomized, double-blind, placebo- and non-steroidal anti-inflammatory drug (NSAID)- controlled study, patients with OA (Kellgren-Lawrence grade ≥ 2; Western Ontario and McMaster Universities Arthritis Index [WOMAC] pain score ≥ 4) received (2:1:1:1) fasinumab 1 mg every 4 weeks, diclofenac 75 mg twice daily, celecoxib 200 mg daily, or placebo for 24 weeks. Co‑primary endpoints were change in WOMAC pain and physical function scores to Week 24 versus placebo. For safety, joints were imaged in all patients at pre‑specified times, regardless of symptoms.

Key findings of the study were:

Of 4531 patients screened, 1650 were randomized. At Week 24, greater improvements were observed for fasinumab versus placebo; least-squares mean difference: –0.63 (p = 0.0003) for WOMAC pain and –0.64 (p = 0.0003) for physical function. Improvements were numerically greater for fasinumab versus NSAIDs for physical function (–0.64 versus –0.31; nominal p < 0.05) and pain (–0.63 versus − 0.39; p = NS). Adjudicated arthropathies occurred in 1.6% of placebo-treated, 1.5% of NSAID-treated, and 5.6% of fasinumab-treated patients; joint replacements occurred in 3.6% of placebo-treated, 4.8% of NSAID-treated, and 3.4% of fasinumab-treated patients.

The authors concluded that – “In this difficult-to-treat population of patients with moderate-to-severe pain due to OA of the knee or hip, fasinumab 1 mg Q4W for 24 weeks resulted in statistically significant greater improvements in WOMAC pain and physical function subscale scores than placebo, and numerically greater improvements in WOMAC pain scores and nominally statistically significant greater improvement in WOMAC physical function scores than NSAIDs. The safety profile was consistent with that previously reported for fasinumab and the class of anti-NGF compounds in general. An increased risk of AAs was observed in the fasinumab group compared with the NSAIDs and placebo groups.”

Further reading:

Efficacy and safety of fasinumab in an NSAID-controlled study in patients with pain due to osteoarthritis of the knee or hip DiMartino et al. BMC Musculoskeletal Disorders (2025) 26:192 https://doi.org/10.1186/s12891-025-08402-8