A randomized, double-blind, placebo-controlled 12 week trial of acetaminophen extended release for the treatment of signs and symptoms of osteoarthritis

AbstractObjective:Determine efficacy and safety of acetaminophen extended release (ER) 1300 mg given three times daily compared to placebo for relieving signs and symptoms of hip or knee osteoarthritis.Research design and methods:Sixty investigators at 58 private, ambulatory, primary care sites in the US enrolled 542 outpatient adults ≥40 years old with moderate to severe idiopathic osteoarthritis pain into a randomized, placebo-controlled, double-blind 12 week clinical trial. Patients were randomly assigned to treatment given three times daily of acetaminophen 1300 mg (n = 267) or placebo (n = 275).Results:The three primary endpoints measured through week 12 favored acetaminophen ER as follows: least squares (LS) mean change from baseline for WOMAC physical function subscale score was significantly greater for acetaminophen ER than for placebo (P = 0.011); LS mean patient’s global assessment of response to therapy was significantly greater for acetaminophen ER than for placebo (P = 0.010); and LS mean ch...