Seven hundred three subjects completed a randomized, double-blind, parallel-group, single-center study comparing the single-dose efficacy of ketoprofen 12.5 mg, ketoprofen 25 mg, acetaminophen 1000 mg, and placebo in the treatment of tension headache.
For the primary efficacy variable, 4-hour sum of pain relief intensity differences, ketoprofen 25 mg was significantly superior to placebo. Ketoprofen 25 mg also demonstrated superior pain relief in the first hour after dosing, and the time to meaningful pain relief was significantly shorter for the ketoprofen 25-mg group. Ketoprofen 12.5 mg proved to be significantly superior to placebo for pain relief intensity difference and pain relief at 3 hours, global assessment of medication at 4 hours, and for time to onset of meaningful pain relief. The data suggest a dose response for ketoprofen 12.5 mg and 25 mg.Acetaminophen 1000 mg proved to be numerically more favorable than placebo in most variables, but could not be separated from placebo with statistical significance. In spite of possible inflation of the placebo response due to sensitivity limits of the study, ketoprofen 25 mg demonstrated a more rapid onset of analgesia compared to acetaminophen 1000 mg, and patients' global assessment rated ketoprofen 25 mg higher than acetaminophen 1000 mg.