Clin J Pain. 2015 May 8
Authors: Raskin P1 et al
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).
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.
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.
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.