A double‐blind, randomized trial of duloxetine versus placebo in the management of chronic low back pain

TLDR

Duloxetine has demonstrated analgesic effect in chronic pain states. This study assessed the efficacy of duloxetine versus placebo in adults with non‑radicular chronic low back pain over a 13‑week, double‑blind, randomized trial. The trial compared duloxetine 20, 60, or 120 mg daily to placebo, with the primary outcome being weekly mean 24‑hour average pain and secondary outcomes including RMDQ‑24, PGI‑I, BPI, and safety, enrolling 404 patients of whom 267 completed. Duloxetine 60 mg produced significant pain relief and functional improvements from weeks 3–11 but did not maintain superiority at week 13, while higher doses increased adverse‑event discontinuations and overall there was no sustained benefit over placebo.

Abstract

Duloxetine has demonstrated analgesic effect in chronic pain states. This study assesses the efficacy of duloxetine in chronic low back pain (CLBP).Adult patients with non-radicular CLBP entered this 13-week, double-blind, randomized study comparing duloxetine 20, 60 or 120 mg once daily with placebo. The primary measure was comparison of duloxetine 60 mg with placebo on weekly mean 24-h average pain. Secondary measures included Roland-Morris Disability Questionnaire (RMDQ-24), Patient's Global Impressions of Improvement (PGI-I), Brief Pain Inventory (BPI), safety and tolerability.Four hundred four patients were enrolled, 267 completed. No significant differences existed between any dose of duloxetine and placebo on reduction in weekly mean 24-h average pain at end-point. Duloxetine 60 mg was superior to placebo from weeks 3-11 in relieving pain, but not at weeks 12-13. Duloxetine 60 mg demonstrated significant improvement on PGI-I, RMDQ-24, BPI-average pain and BPI-average interference. Significantly more patients taking duloxetine 120 mg (24.1%) discontinued because of adverse events, versus placebo (8.5%).Duloxetine was superior to placebo on the primary objective from weeks 3-11, but superiority was not maintained at end-point. Duloxetine was superior to placebo on many secondary measures, and was well-tolerated.