Pregabalin relieves symptoms of painful diabetic neuropathy - A randomized controlled trial

Objective: Pregabalin, an alpha(2)-delta ligand with analgesic, anxiolytic, and anticonvulsant activity, has been evaluated for treatment of neuropathic pain. The authors assessed the efficacy and tolerability of pregabalin ( 75, 300, 600 mg/day) vs placebo in patients with diabetic peripheral neuropathy (DPN). Methods: Patients with a 1- to 5-year history of DPN and average weekly pain score of greater than or equal to4 on an 11-point numeric pain-rating scale were enrolled in a 5-week, double-blind, multicenter, placebo-controlled study. Patients ( n = 338) were randomized to receive one of three doses of pregabalin or placebo TID. Pregabalin 600 mg/day was titrated over 6 days; lower doses were initiated on day 1. Results: Patients in the 300- and 600-mg/day pregabalin groups showed improvements in endpoint mean pain score ( primary efficacy measure) vs placebo ( p = 0.0001). Improvements were also seen in weekly pain score, sleep interference score, patient global impression of change, clinical global impression of change, SF-McGill Pain Questionnaire, and multiple domains of the SF-36 Health Survey. Improvements in pain and sleep were seen as early as week 1 and were sustained throughout the 5 weeks. Responders ( patients with greater than or equal to 50% reduction in pain compared to baseline) were 46% ( 300 mg/day), 48% ( 600 mg/day), and 18% ( placebo). Pregabalin was well tolerated with a low discontinuation rate. The most common adverse events were dizziness and somnolence. Conclusions: In patients with diabetic peripheral neuropathy, pregabalin demonstrated early and sustained improvement in pain and a beneficial effect on sleep, which were confirmed by positive patient global impression. Pregabalin was well tolerated at all doses.