PAIN
Research papers
Duloxetine, a centrally acting analgesic, in the treatment of patients with osteoarthritis knee pain: A 13-week, randomized, placebo-controlled trial
Chappell, Amy S.a,*; Ossanna, Melissa J.a; Liu-Seifert, Honga; Iyengar, Smritia; Skljarevski, Vladimira; Li, Linda Chunhongb; Bennett, Robert M.c; Collins, Harryd
aLilly Research Laboratories, Indianapolis, IN, USA
bi3 Statprobe, Ann Arbor, MI, USA
cOregon Health & Science University, Portland, OR, USA
dAnderson & Collins Clinical Research, Inc., Edison, NJ, USA
*Corresponding author. Tel.: +1 317 277 3846; fax: +1 317 276 6026.
E-mail address:[email protected]
ARTICLE INFO
Article history:
Received June 11, 2008
Received in revised form June 1, 2009
Accepted June 18, 2009.
Abstract
Pain is a common cause of disability in osteoarthritis. Duloxetine, a serotonin and norepinephrine reuptake inhibitor (SNRI), has demonstrated analgesic effects in diabetic peripheral neuropathy and fibromyalgia. Considering its central mechanism of action, duloxetine may be effective in other pain states with evidence of central sensitization. Herein, we report the results of a 13-week, randomized, double-blind, placebo-controlled trial of duloxetine (60–120 mg/day) versus placebo in the treatment of knee pain in 231 patients meeting clinical and radiographic criteria for osteoarthritis of the knee. Duloxetine was superior to placebo on the primary efficacy measure (weekly mean 24-h pain scores) beginning at Week 1 and continuing through the treatment period (P ≤ .05). There was also a significant improvement in the WOMAC physical functioning subscale and several other secondary outcomes. Adverse-event rates did not differ significantly between treatment groups (49.5% for duloxetine 60–120 mg/day, and 40.8% for placebo).