Efficacy and safety of pregabalin for painful diabetic peripheral neuropathy in a population of Chinese patients: A randomized placebo-controlled trial

BackgroundLimited information exists regarding the efficacy of pregabalin in Chinese patients with painful diabetic peripheral neuropathy (pDPN). MethodsAn 11-week double-blind placebo-controlled trial was performed in Chinese pDPN patients randomized (1 : 1) to 300 mg/day pregabalin or placebo. The primary outcome was change from baseline to endpoint in mean pain score (MPS; 0, no pain; 10, worst possible pain; using the mean of the last seven daily pain scores). Secondary outcomes included weekly MPS and responder status (MPS reduced by 30% or 50% vs baseline). Subgroup analysis assessed patients with severe (7) baseline MPS. Adverse events (AEs) were reported. ResultsIn all, 620 patients were randomized (pregabalin, n = 313; placebo, n = 307). Improvement in MPS with pregabalin versus placebo was not significant (P = 0.0559). Post hoc sensitivity analyses, excluding one patient/site due to Good Clinical Practice (GCP) non-compliance, showed pregabalin significantly improved MPS when excluding the patient (P = 0.0448) or site (P = 0.0142). Pregabalin significantly improved weekly MPS (P = 0.0164) and 50% responders at endpoint (P = 0.0384). Improvement in proportion of 30% responders, impression of change, pain intensity, and sleep did not differ significantly between the treatment groups. In the severe pDPN subpopulation, pregabalin significantly improved MPS versus placebo (P = 0.0040). The most commonly reported AE was dizziness (9.6% vs 3.9% with placebo). ConclusionsPregabalin did not significantly improve the primary measure of pain in the trial. Significant reductions in MPS were observed when excluding the GCP non-compliant patient/site and in the severe pDPN subpopulation. Pregabalin was well tolerated in Chinese pDPN patients.