Efficacy of etoricoxib 60 mg/day and diclofenac 150 mg/day in reduction of pain and disability in patients with chronic low back pain: results of a 4‐week, multinational, randomized, double-blind study

Abstract

ABSTRACTBackground and methods: The efficacy and safety of etoricoxib 60 mg/day in patients with established chronic low back pain (CLBP) were compared with those of diclofenac 150 mg/day in a 4‐week, multicentre, randomized, double-blind, parallel-group trial. Four hundred and forty-six adult patients with CLBP (Quebec Task Force on Spinal Disorders Class 1 or 2) and with worsening pain upon discontinuation of pre-study analgesic medication were enrolled in the study.The study primary efficacy endpoint was change from baseline in Low Back Pain Intensity Scale (LBP‐IS) score over the 4‐week treatment period. Secondary and other efficacy endpoints included: changes in Roland and Morris Disability Questionnaire (RMDQ), Patient Global Assessment of Response to Therapy (PGART) and Low Back Pain Bothersomeness Scale (LBP-BS) scores. Early efficacy was assessed using PGART and LBP‐IS scores 4 h after the first dose on the mornings of Days 1, 2 and 3. The overall safety and tolerability of etoricoxib 60 mg/day during 4 weeks of treatment were also assessed.Results: The least-squares mean time-weighted change from baseline LBP‐IS score over 4 weeks was –32.94 mm (95% CI –36.25, –29.63) for etoricoxib, indicating substantial efficacy in relief of pain. The treatment difference for the primary outcome was 2.51 mm (95% CI –1.50, 6.51), fulfilling the prespecified equivalence criterion of 95% confidence interval wholly within ± 10 mm. Etoricoxib improved all secondary and other efficacy outcomes.There were no statistically significant between-group differences in the proportion of patients with one or more clinical adverse events (AEs) (etoricoxib 35%, diclofenac 39%), or the proportion of patients who discontinued due to AEs (etoricoxib 7%, diclofenac 5%).Conclusions: The results of this study confirm that, for adult patients with CLBP, etoricoxib 60 mg once daily over 4 weeks is effective for relief of pain and improvement of physical function and comparable to high-dose diclofenac 150 mg daily.