Clin J Pain. 2015 May 8
Authors: Raskin P1 et al
OBJECTIVES:
To evaluate pregabalin’s efficacy and safety versus placebo to reduce pain in subjects with diabetic peripheral neuropathy (DPN) using a concomitant nonsteroidal anti-inflammatory drug (NSAID).
METHODS:
In a randomized, double-masked, 14-week, 2-period, crossover study, subjects with painful DPN using an NSAID for non-DPN-related pain received 150-300▒mg/d pregabalin or placebo (Period 1); 14-day washout; then, the opposite therapy (Period 2). Endpoints included weekly change in DPN pain score, sleep interference, adverse events (AE), and patient-reported outcomes.
RESULTS:
Subjects with similar baseline characteristics were randomized (Period 1) to 1 of the 2 following possible sequences: pregabalin→placebo (n=154) or placebo→pregabalin (n=147). Results of the primary efficacy measure, mean weekly DPN pain at endpoint, showed no significant difference between pregabalin and placebo. However, one sensitivity analysis (mixed-model repeated measures) found greater pain score reductions with pregabalin than placebo at weeks 2-4 and overall (all P<0.05). One secondary endpoint analysis, mean treatment difference in DPN-related sleep interference, favored pregabalin over placebo (P=0.0009). Other sensitivity and secondary analyses were non-significant. Treatment-emergent AEs were consistent with the known safety profile of pregabalin.
DISCUSSION:
Pregabalin (vs. placebo) showed overall improvements in sleep, pain reduction in one sensitivity analysis, and was well tolerated. Potential factors that may have confounded the ability to detect a treatment difference in DPN pain reduction (high placebo response, carryover effect, short washout period, or pregabalin dose) are discussed in the context of future studies.