Abstract

Objective: To evaluate efficacy and safety of lacosamide compared with placebo in painful diabetic polyneuropathy.

Research Design and Methods: Diabetic patients with at least moderate neuropathic pain were randomized to placebo or lacosamide 400 (in a slow or standard titration) or 600mg/day over 6-week titration and 12-week maintenance periods. Primary efficacy criterion was intra-individual change in average daily Numeric Pain Rating Scale score from baseline to the last 4 weeks.

Results: For the primary endpoint, pain reduction was numerically but not statistically greater with lacosamide compared with placebo (400mg/day,P=0.12;600mg/day,P=0.18). Both doses were significantly more effective compared with placebo over the titration (P=0.03,P=0.006), maintenance (P=0.01,P=0.005), and entire treatment periods (P=0.03,P=0.02). Safety profiles between titration schemes were similar.

Conclusions: Lacosamide reduced neuropathic pain and was well tolerated in diabetic patients, but the primary efficacy criterion was not met, possibly due to an increased placebo response over the last 4 weeks.