Pregabalin, which is approved for the treatment epilepsy, neuropathic pain, generalized anxiety and fibromyalgia, was well tolerated in patients with RLS and “is a promising alternative to current treatments because of its superior effects on quality of sleep,” Dr. Diego Garcia-Borreguero, director of the Sleep Research Institute in Madrid, Spain, noted in a statement from the meeting.
The study involved 58 patients with idiopathic RLS. After a 2-week placebo run-in period, 30 patients were assigned to pregabalin (150 to 600 milligrams daily) and 28 to placebo for 12 weeks. RLS severity was determined periodically using the International RLS rating scale, as well as other disease severity measures, and sleep studies were performed at baseline and 12 weeks.
According to Dr. Garcia-Borreguero and colleagues, the change in International RLS rating scale scores was significantly “more pronounced” with pregabalin than with placebo. With pregabalin, scores on this disease severity index declined from 19.8 to 6.8; with placebo, scores declined from 21.5 to 11.2 (p = 0.02).
Similar findings were observed with other disease severity tools, according to the investigators.
In addition, 63.3% of pregabalin-treated patients had remission of RLS symptoms while taking the drug at a mean daily dose of 337 milligrams. In comparison, only 28.6% of placebo-treated patients achieved remission.
Pregabalin treatment also improved sleep architecture in RLS patients, with a significant increase in time spent in deep slow wave Stage 3 sleep and a decrease in time spent in lighter stage 1 or 2 sleep, compared to patients on placebo.
“Pregabalin,” Dr. Garcia-Borreguero and colleagues conclude, “is a promising alternative to current dopaminergic treatments (for RLS) due to its superior therapeutic effects on sleep architecture.”