A study of the dose-response of YM177 for treatment of postsurgical dental pain

Abstract

A multicenter, double-blind, placebo-controlled, parallel group comparative study was conducted to demonstrate the dose-response relationship of YM177, and to determine its recommended dose. YM177 is a selective inhibitor of COX-2, Which is associated with pain following the extraction of mandibular-impacted wisdom teeth. Global improvement rates and patients' subjective impressions were established as primary parameters. Five doses of YM177 (25, 50, 100, 200, and 400 mg), plus a placebo, were studied. Global improvement rates and subjective efficacy rates, as reported by patients, demonstrated significant differences when compared with placebo in patients receiving doses of 25 mg or more. Moreover, among the five YM177 dose groups, we found greater improvement and efficacy rates with increasing doses. In addition, the YM177 200 mg group, and the YM177 400 mg group, showed improvement rates of 70% or greater in all primary parameters of evaluation, demonstrating significant efficacy of YM177 as a therapeutic drug. As to the drug's safety, no serious adverse events developed in any patient of the YM177 dosage groups.
It is therefore considered that both 200 mg and 400 mg are clinically effective doses, in line with the definition of “dose selection” pre-determined in this study.