Novel p38α Mitogen-Activated Protein Kinase Inhibitor Shows Analgesic Efficacy in Acute Postsurgical Dental Pain.

SCIO-469 is a selective p38α mitogen-activated protein kinase (MAPK) inhibitor for preclinical models of acute pain. This prospective, double-blind, randomized clinical study compared efficacy and safety of oral SCIO-469, ibuprofen, and placebo in postsurgical dental pain. Subjects (n = 263) undergoing extraction of 1 or more impacted mandibular third molars received preoperative treatment with SCIO-469 (150, 210, or 300 mg), ibuprofen (400 mg), or placebo; the 210-mg group received 90 mg postoperatively. A 4-point categorical scale and a 100-mm visual analogue scale were used to measure pain intensity. The primary end point was median time from first incision to first rescue medication using the Kaplan-Meier product limit estimator. All SCIO-469 groups had significantly longer times to rescue medication compared with placebo; preoperative and postoperative treatment with 210 + 90 mg SCIO-469 resulted in 8.1 hours versus 4.1 hours to rescue for placebo (P = .003). Ibuprofen also increased time to rescue medication (6.6 hours) versus placebo (P = .04). Dizziness, headache, and nausea were the most frequently reported adverse events. This is the first clinical demonstration of antinociceptive effects in acute pain with preoperative administration of a p38α MAPK inhibitor.