Juergen Reess

Efficacy of pramipexole in restless legs syndrome: A six‐week, multicenter, randomized, double‐blind study (effect‐RLS study)

We evaluated the efficacy of pramipexole versus placebo in restless legs syndrome (RLS) for 6 weeks. Overall, 345 patients were randomly assigned in a 1:2 ratio to receive either placebo (n = 115) or pramipexole (n = 230) with a starting dose of 0.125 mg/day. The dose was individually optimized according to the Patient Global Impression (PGI) assessment, up to a maximum of 0.75 mg/day. The primary endpoint consisted of two assessments: the change from baseline in the International RLS Study Group Rating Scale (IRLS) and the proportion of patients with Clinical Global Impressions‐Improvement (CGI‐I) assessments of “much/very much improved” (CGI‐I responders) at week 6. Secondary endpoints included PGI and IRLS responder rates. Patient demographics and baseline characteristics were comparable between treatment groups. At baseline, mean IRLS scores were 24.9 (placebo) and 24.7 (pramipexole), representing severely affected patients. After 6 weeks, adjusted mean reductions (±SE) in IRLS score were 5.7 (±0.9) for placebo (median dose 0.47 mg/day) and 12.3 (±0.6) for pramipexole (median dose 0.35 mg/day; P < 0.0001). CGI‐I responder rates were 32.5% (placebo) and 62.9% (pramipexole) (P < 0.0001). For all secondary endpoints, pramipexole showed superior results. Pramipexole was well tolerated throughout the study.

Controlled withdrawal of pramipexole after 6 months of open-label treatment in patients with restless legs syndrome.

Although dopamine agonists are becoming first‐line therapy for restless legs syndrome (RLS), few reports describe treatment periods exceeding 12 weeks. Here, 150 RLS patients who had responded to pramipexole during a 6‐month run‐in period (mean dose, 0.50 mg) were randomly assigned to receive placebo or continue receiving pramipexole at an individually optimized dose of 0.125 to 0.75 mg/day for a further 3 months. Patients switched to placebo reached the primary endpoint (a predefined worsening on both the Clinical Global Impressions‐Global Improvement scale and the International RLS Study Group Rating Scale) significantly more often than patients who continued to receive pramipexole (85.5% vs. 20.5%; P < 0.0001). They also reached the primary endpoint faster, in 5 versus 42 days to a Kaplan–Meier survival estimate of 0.85 and 7 versus > 84 days to an estimate of 0.5. Over the total 9 months, clinician and patient ratings of symptoms, sleep, and quality of life identified no decline in pramipexoles benefit or tolerability. The great majority of adverse events (AEs) were mild or moderate, and of expected types. Augmentation was considered an AE, but in this population of responders it did not occur.