title: A double-blind, randomized, placebo-controlled study of the efficacy and safety of duloxetine for the treatment of chronic pain due to osteoarthritis of the knee.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of duloxetine in the treatment of chronic pain due to osteoarthritis of the knee.
  
  
  METHODS
  This was a 13-week, randomized, double-blind, placebo-controlled trial in patients meeting American College of Rheumatology clinical and radiographic criteria for osteoarthritis of the knee. At baseline, patients were required to have a ≥ 4 weekly mean of the 24-hour average pain ratings. Patients were randomized to either duloxetine 60 mg once daily (QD) or placebo. At week 7, the duloxetine dosage was increased, in a blinded fashion, to 120-mg QD in patients reporting < 30% pain reduction. The primary efficacy measure was Brief Pain Inventory (BPI) 24-hour average pain. Secondary efficacy measures included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC); Clinical Global Impressions of Severity (CGI-S). Safety and tolerability was also assessed.
  
  
  RESULTS
  Of the total (n = 256) patients, 111 (86.7%) in placebo group and 93 (72.7%) in duloxetine group completed the study. Patients treated with duloxetine had significantly (P ≤ 0.001) greater improvement at all time points on BPI average pain and had significantly greater improvement on BPI pain severity ratings (P ≤ 0.05), WOMAC total (P = 0.044) and physical functioning scores (P = 0.016), and CGI-S (P = 0.009) at the study endpoint. Frequency of treatment-emergent nausea, constipation, and hyperhidrosis were significantly higher in the duloxetine group (P ≤ 0.05). Significantly more duloxetine-treated patients discontinued the trial because of adverse events (P = 0.002).
  
  
  CONCLUSIONS
  Treatment with duloxetine 60 mg to 120 mg QD was associated with significant pain reduction and improved function in patients with pain due to osteoarthritis of the knee.
authors.affiliation: Lilly Research Laboratories, Indianapolis, Indiana 46285, USA.
authors.forename: Amy S
authors.initials: AS
authors.lastname: Chappell
authors.forename: Durisala
authors.initials: D
authors.lastname: Desaiah
authors.forename: Hong
authors.initials: H
authors.lastname: Liu-Seifert
authors.forename: Shuyu
authors.initials: S
authors.lastname: Zhang
authors.forename: Vladimir
authors.initials: V
authors.lastname: Skljarevski
authors.forename: Yuri
authors.initials: Y
authors.lastname: Belenkov
authors.forename: Jacques P
authors.initials: JP
authors.lastname: Brown
mesh_terms: D000368:Aged; D000700:Analgesics / Q000627:therapeutic use*; D002908:Chronic Disease; D004311:Double-Blind Method; D000068736:Duloxetine Hydrochloride; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications* / Q000188:drug therapy; D010146:Pain / Q000188:drug therapy* / Q000209:etiology*; D010147:Pain Measurement; D012720:Severity of Illness Index; D013876:Thiophenes / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000700:Analgesics; D013876:Thiophenes; D000068736:Duloxetine Hydrochloride