Randomized polysomnography study of gabapentin enacarbil in subjects with restless legs syndrome.

We assessed the efficacy and tolerability of gabapentin enacarbil in the treatment of moderate to severe primary restless legs syndrome and associated sleep disturbance. This was a multicenter, randomized, double-blind, placebo-controlled, 2-period crossover polysomnography study of gabapentin enacarbil 1200 mg or placebo taken once daily. Subjects were randomized 1:1 to a sequence of gabapentin enacarbil:placebo or placebo:gabapentin enacarbil, receiving each treatment for 4 weeks. The primary end point was the mean change from baseline at weeks 4 and 10 (4/10) last observation carried forward in wake time during sleep. The key secondary end point was the mean change from baseline at weeks 4/10 last observation carried forward in periodic limb movements associated with arousal per hour of sleep. Tolerability assessments included adverse events. One hundred thirty-six subjects were randomized (gabapentin enacarbil:placebo, 67; placebo:gabapentin enacarbil, 69), and 114 (gabapentin enacarbil:placebo, 53; placebo:gabapentin enacarbil, 61) completed the study. Gabapentin enacarbil 1200 mg significantly reduced wake time during sleep (mean change from baseline [adjusted mean treatment difference]: -26.0 minutes; P < .0001) and periodic limb movements associated with arousal per hour of sleep (adjusted mean treatment difference: -3.1 periodic limb movements with arousal/hour; P = .002) compared with placebo at weeks 4/10 last observation carried forward. The most commonly reported adverse events were dizziness (gabapentin enacarbil 20%, placebo 2%) and somnolence (gabapentin enacarbil 13%, placebo 2%). Gabapentin enacarbil 1200 mg once daily significantly reduces restless legs syndrome-associated sleep disturbance and periodic limb movements associated with arousal per hour of sleep and is generally well tolerated in adults with moderate to severe primary restless legs syndrome.

Psychometric evaluation and tests of validity of the Medical Outcomes Study 12-item Sleep Scale (MOS sleep).

OBJECTIVE: To validate the psychometric properties of the Medical Outcomes Study (MOS) Sleep Scale in subjects with restless legs syndrome (RLS). METHODS: Data from a clinical trial program involving two Phase III, double-blind, placebo-controlled trials of ropinirole in subjects with moderate-to-severe primary RLS were analyzed. Subjects were assessed on the MOS Sleep Scale at baseline, Weeks 8 and 12. RESULTS: The baseline validation population included 551 subjects on which full longitudinal data are available. Psychometric assessment of four MOS sleep domains revealed satisfactory item convergent validity (r > 0.40) for most items. All domain items in both trials surpassed the standard for item discriminant validity, with no significant floor or ceiling effects. The MOS sleep domain scores showed good internal consistency reliability. Concurrent validity (r = 0.40) was exceeded in correlations between the RLS overall quality-of-life score and sleep problems index II. The clinical validity of the MOS Sleep Scale was demonstrated against self-reported RLS symptoms and clinician-determined severity; changes in MOS Sleep Scale were responsive to improvements in RLS severity, as measured by the Clinical Global Impression-Improvement and Severity-of-Illness scales. CONCLUSION: The MOS Sleep Scale is a reliable, valid tool for assessing changes in the sleep of subjects with moderate-to-severe primary RLS. The somnolence domain failed to relate to clinical severity of RLS, indicating a possible sleep-wake relationship unique to RLS. Use of this scale to evaluate other conditions causing sleep disturbance is supported.

Pharmacodynamic effects of zidovudine 600 mg once/day versus 300 mg twice/day in therapy-naïve patients infected with human immunodeficiency virus.

STUDY OBJECTIVE: To compare the virologic activity of zidovudine monotherapy administered as 600 mg once/day versus 300 mg twice/day. DESIGN: Phase II, randomized (1:1), open-label study. SETTING: Thirteen medical centers in the United States. PATIENTS: Thirty-two antiretroviral-naive patients infected with human immunodeficiency virus (HIV). INTERVENTION: Patients were administered either zidovudine 600 mg every 24 hours (16 patients) or 300 mg every 12 hours (16 patients) for 13 days. MEASUREMENTS AND MAIN RESULTS: Plasma HIV-1 RNA concentration was measured daily. Study end points were between-group differences in change from baseline of log10-transformed HIV-1 RNA and in rates of viral load decline measured by the slope of HIV-1 RNA over time. At baseline, mean HIV-1 RNA was similar in the once/day and twice/day groups (4.33 and 4.40 log10 copies/ml, respectively). At day 14, a trend toward lower mean reduction in HIV-1 RNA from baseline was observed in the once/day group (-0.585, 95% confidence interval [CI] -0.728 to -0.442 log10 copies/ml) compared with the twice/day group (-0.849, 95% CI -1.067 to -0.630 log10 copies/ml, p=0.056). Viral load reduction also tended to be slower in the once/day group, as indicated by the smaller slope of viral load decline in the once/day group than in the twice/day group during days 1-14 (-0.045 vs -0.065 logic copies/ml/day, p=0.065). Both zidovudine regimens were similarly well tolerated. CONCLUSION: Zidovudine 600 mg once/day has antiviral activity, although less pronounced and more slowly achieved than that seen with zidovudine 300 mg twice/day. No differences were observed between the two treatment groups with respect to safety profile or tolerability