An Open-Label, 52-Week, Phase III Trial of Duloxetine in Japanese Patients with Chronic Low Back Pain

Pain Med. 2019 Aug 1;20(8):1479-1488. doi: 10.1093/pm/pnz027.

Abstract

Objective: To evaluate the safety and efficacy of duloxetine treatment for 52 weeks.

Design: Multicenter, open-label, phase III clinical study.

Setting: Forty-one medical institutions in Japan.

Subjects: Japanese patients with chronic low back pain (CLBP).

Methods: Duloxetine 60 mg once-daily was administered for 52 weeks. Safety was evaluated based on adverse events (AEs), vital signs, laboratory test values, electrocardiogram, Columbia-Suicide Severity Rating Scale, and occurrence of falls. The efficacy outcome measures were the Brief Pain Inventory (BPI; average pain, worst pain, least pain, and pain right now), BPI Interference, Patient's Global Impression of Improvement (PGI-I), Clinical Global Impressions of Severity (CGI-S), Roland-Morris Disability Questionnaire-24 (RDQ-24), 36-Item Short-Form Health Survey (SF-36), and European Quality of Life-5 Dimensions Questionnaire (EQ-5D).

Results: In total, 151 patients (83 who completed a 14-week placebo-controlled superiority trial and 68 newly registered patients) were enrolled. The incidence rates of AEs and adverse drug reactions (ADRs) were 86.1% and 50.3%, respectively. ADRs with an incidence of ≥5% were somnolence, constipation, nausea, and dry mouth. Treatment discontinuation for AEs occurred in 16 patients. A significant reduction in the BPI average pain score (mean ± SD) was observed at all assessment time points from week 2 (-1.02 ± 1.37) to week 50 (-2.26 ± 1.63), compared with baseline. BPI pain severity (worst pain, least pain, and pain right now), BPI Interference, PGI-I, CGI-S, RDQ-24, SF-36, and EQ-5D showed significant improvement.

Conclusion: Japanese patients with CLBP had significant pain reduction over 52 weeks without new safety concerns.

Keywords: Chronic Low Back Pain; Duloxetine; Efficacy; Japan; Long Term; Safety.

Publication types

  • Clinical Trial, Phase III
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Analgesics / therapeutic use*
  • Chronic Pain / drug therapy*
  • Constipation / chemically induced
  • Duloxetine Hydrochloride / therapeutic use*
  • Female
  • Humans
  • Japan
  • Low Back Pain / drug therapy*
  • Male
  • Middle Aged
  • Nausea / chemically induced
  • Pain Measurement
  • Sleepiness
  • Triethylenemelamine
  • Xerostomia / chemically induced

Substances

  • Analgesics
  • Duloxetine Hydrochloride
  • Triethylenemelamine