Pfizer Issues Top-Line Results from Potherpetic Neuralgia, Painful Diabetic Peripheral Neuropathy Studies in China: PDPN Phase 3 Did Not Hit Endpoint, PHN Phase 4 Study Met Primary Endpoint

Pfizer Inc.

announced today top-line results from two placebo-controlled studies conducted in China with Lyrica^® (pregabalin) in patients with postherpetic neuralgia (pain after shingles or PHN) and painful diabetic peripheral neuropathy (pDPN), respectively. The PHN Phase 4 study, A0081276, met its primary endpoint by demonstrating a statistically significant reduction in pain when compared to placebo. Separately, the pDPN Phase 3 study, A0081265, did not meet its primary endpoint, a statistically significant change in endpoint mean pain score relative to placebo. The PHN study was an eight-week, randomized, double-blind, multi-center, placebo-controlled, post-marketing study evaluating the efficacy, safety and tolerability of pregabalin 300mg/day in the treatment of subjects with PHN. For the primary efficacy parameter, change from baseline in weekly mean pain scores (0-10 numeric rating scale), a significant treatment difference of -0.71 points for pregabalin relative to placebo was observed (p=0.0002). The safety profile in this study was consistent with the known profile for Lyrica. The most common adverse events reported for subjects given Lyrica were dizziness, oedema peripheral, dry mouth and somnolence. PHN is a type of peripheral neuropathic pain caused by nerve damage. PHN symptoms include continued burning or electric shock-like pain.^1 The pDPN study was a 11-week randomized, double-blind, multi-center, placebo-controlled study evaluating the efficacy, safety and tolerability of pregabalin 300 mg/day in the treatment of subjects with pDPN. For the primary efficacy parameter, endpoint mean pain score (0-10 numeric rating scale), a treatment difference of -0.28 points for pregabalin relative to placebo was observed (p=0.0559). The safety profile of pregabalin in this study was consistent with the known profile for Lyrica. The most common adverse events reported by subjects given Lyrica were dizziness and somnolence. pDPN is a form of permanent nerve damage characterized by burning, shooting, pins-and-needles pain in the feet and hands^2. Full results for both studies will be submitted for publication when analyses are complete.