title: Pregabalin for Neuropathic Pain: Why Benefits Could Be Expected for Multiple Pain Conditions.
abstract: OBJECTIVE
  Limited research exists to support the extrapolation of the analgesic efficacy of pregabalin from one neuropathic pain condition to another. This retrospective analysis evaluated similarities in the efficacy of pregabalin for treating neuropathic pain associated with post-herpetic neuralgia (PHN), diabetic peripheral neuropathy (DPN), and spinal cord injury (SCI) in a Japanese population, as a basis for considering the extrapolation of these data to other neuropathic pain conditions.
  
  
  METHODS
  Data were analysed across pregabalin doses within each pain condition, from three comparable 13- to 16-week, randomized, double-blind, placebo-controlled trials (RCTs) and the corresponding 52-week, open-label extension trials of pregabalin in Japanese patients with PHN, DPN or SCI. Efficacy outcomes in the RCTs included endpoint and weekly mean pain and sleep interference scores; endpoint proportions of responders in pain; Patient Global Impression of Change scores; and 36-Item Short Form Health Survey (SF-36) scores or Hospital Anxiety and Depression Scale (HADS) assessments. Study discontinuation rates were compared between treatment groups. The extension trials assessed pain intensity, using the Short-Form McGill Pain Questionnaire.
  
  
  RESULTS
  In the RCTs for all pain conditions, significant improvements in comparison with placebo in mean pain and sleep interference scores were evident after 1 week with pregabalin and were sustained throughout the treatment periods (p < 0.05). At the study endpoint, in comparison with placebo, a significantly greater percentage of pregabalin-treated patients experienced a ≥30 % reduction in pain across the RCTs (p < 0.05), and pregabalin significantly improved six of 16 SF-36 subscale scores in the PHN and DPN trials (p < 0.05). In the SCI trial, pregabalin-treated patients had numerically better outcomes of HADS scores. In the extension trials, improvements in pain intensity were maintained over a 52-week period.
  
  
  CONCLUSIONS
  Similarities in the pregabalin efficacy profiles, including time to onset and magnitude of response, were confirmed regardless of the neuropathic pain condition. These data support the potential for extrapolating analgesic efficacy to other neuropathic pain conditions. CLINICALTRIALS.
  NCT00394901, NCT00553475, NCT00407745, NCT00424372, NCT00553280, NCT01202227.
authors.affiliation: Department of Anesthesiology, Nihon University School of Medicine/Surugadai Nihon University Hospital, Tokyo, Japan.
authors.forename: Setsuro
authors.initials: S
authors.lastname: Ogawa
authors.affiliation: Portfolio and Project Management, Pfizer Japan Inc., Tokyo, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Arakawa
authors.affiliation: Medical Affairs, Pfizer Japan Inc., Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hayakawa
authors.affiliation: Clinical Statistics, Pfizer Japan Inc., 3-22-7 Yoyogi, Shibuya-ku, Tokyo, 151-8589, Japan. tamotsu.yoshiyama@pfizer.com.
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Yoshiyama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000700:Analgesics / Q000008:administration & dosage; D003929:Diabetic Neuropathies / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000188:drug therapy*; D051474:Neuralgia, Postherpetic / Q000188:drug therapy*; D010147:Pain Measurement; D000069583:Pregabalin / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000700:Analgesics; D000069583:Pregabalin