A study depicted that in patients with chronic low back pain, fasinumab (at an elevated dose of 9 mg) was linked with functional improvement and a decrease in chronic low back pain. However, lower doses of fasinumab offered less benefit.

A phase II/III, randomized, double-dummy, double-blind, placebo-controlled trial was carried out to explore the safety and efficacy of fasinumab (a fully human monoclonal antibody that targets nerve growth factor) in moderate-to-severe chronic low back pain. The study cohort included individuals with chronic low back pain (age ≥35 years) with unsatisfactory pain relief/intolerance to opioids, acetaminophen, and non-steroidal anti-inflammatory agents.

Overall, 563 participants were randomized to fasinumab 6 mg subcutaneous every four weeks (Q4W, n=141), fasinumab 9 mg subcutaneous Q4W (n=140), fasinumab 9 mg intravenously every eight weeks (Q8W, n=141) or placebo (n=140). The alteration in the average daily low back pain intensity numeric rating score from baseline to 16th week was the primary outcome parameter. The Patient Global Assessment (PGA) and the Roland-Morris Disability Questionnaire (RMDQ) were the secondary efficacy variables ascertained.

At week 16, a substantial placebo-adjusted decline in low back pain intensity was witnessed for 9 mg of fasinumab Q4W and Q8W, but not 6 mg. The RMDQ and PGA improvements to week 16 were considerably better for 9 mg intravenous fasinumab. Over 16 weeks, numerically greater efficacy was witnessed in subjects with peripheral osteoarthritis compared to subjects without peripheral osteoarthritis.

Treatment-associated adverse effects were found to occur in 274/418 (65.6%) subjects in the combined fasinumab groups and 94/140 (67.1%) placebo subjects. Joint adverse effects, majorly rapid progressive osteoarthritis type 1, were more commonly reported in the combined fasinumab cohort (19 events in 16 subjects [3.8%] vs 1 event in 1 subject (0.7%) for placebo); all except one were noted in peripheral osteoarthritis  patients.

Thus, fasinumab appears to be a promising treatment choice for chronic low back pain individuals with unsatisfactory pain control, or who are intolerant/ have contraindication for existing therapies.