Pregabalin for the treatment of postoperative pain: results from three controlled trials using different surgical models

Abstract

Neil K Singla,1 Jacques E Chelly,2 David R Lionberger,3 Joseph Gimbel,4 Luis Sanin,5 Jonathan Sporn,5 Ruoyong Yang,5 Raymond Cheung,5 Lloyd Knapp,6 Bruce Parsons5 1Lotus Clinical Research, Pasadena, CA, USA; 2Division of Acute Interventional Perioperative Pain, Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA; 3Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA; 4Arizona Research Center, Phoenix, AZ, USA; 5Pfizer Inc., New York, NY, USA; 6Pfizer Inc., New London, CT, USA Purpose: To evaluate the efficacy and safety of pregabalin (150 or 300 mg/d) as an adjunctive therapy for the treatment of postoperative pain. Patients and methods: This study reports findings from three separate, multicenter, randomized, double-blind, placebo-controlled trials of adjunctive pregabalin for the treatment of postoperative pain. Patients underwent one of three categories of surgical procedures (one procedure per study): elective inguinal hernia repair (post-IHR); elective total knee arthroplasty (post-TKA); or total abdominal hysterectomy (posthysterectomy). The primary endpoint in each trial, mean worst pain over the past 24 hours, was assessed 24 hours post-IHR and posthysterectomy, and 48 hours post-TKA. Patients rated their pain on a scale from 0 to 10, with higher scores indicating greater pain severity. Results: In total, 425 (post-IHR), 307 (post-TKA), and 501 (posthysterectomy) patients were randomized to treatment. There were no statistically significant differences between the pregabalin and placebo groups with respect to the primary endpoint in any of the three trials. The least squares mean difference in worst pain, between 300 mg/d pregabalin and placebo, was -0.7 (95% confidence interval [CI] =-1.4, -0.1; Hochberg adjusted P=0.067) post-IHR; -0.34 (95% CI =-1.07, 0.39; P=0.362) post-TKA; and -0.2 (95% CI =-0.66, 0.31; P=0.471) posthysterectomy. Conclusion: There were no significant differences between pregabalin and placebo with respect to the primary pain intensity measure in each of the three clinical trials. These studies encompass a large dataset (1,233 patients in total), and their results should be considered when assessing pregabalin's effectiveness in postoperative pain. Further studies are required to determine the potential pain-reducing benefit of pregabalin in the postoperative setting. Keywords: arthroplasty, herniorrhaphy, hysterectomy, postoperative pain, pregabalin