We evaluated the efficacy of
pregabalin in patients with chronic lumbosacral
radiculopathy. This randomized, controlled, withdrawal trial included five phases: screening (4-18 days); run-in (4-10 days) to screen out placebo responders; single-blind (28 days) to identify
pregabalin responders; double-blind to randomize responders to
pregabalin or placebo (35 days); and final study medication taper (7 days). The primary endpoint was time to loss of response (LOR) during the double-blind phase (1-point increase in
pain, discontinuation, or rescue-medication use). In the single-blind phase, 58% of patients had 30%
pain reduction. In the double-blind phase,
pregabalin (n=110) and placebo (n=107) groups did not differ significantly in time to LOR. Adverse events caused the discontinuation of 9.9% and 5.6% of
pregabalin-treated and placebo-treated patients, respectively. Most patients with chronic lumbosacral
radiculopathy responded to
pregabalin therapy; however, time to LOR did not significantly differ between
pregabalin and placebo. Considering the results of all phases of the study, it is difficult to draw definitive conclusions from it, suggesting a need for further work to understand the clinical potential of
pregabalin treatment for lumbosacral
radiculopathy.