A fixed-dose, dose-response study of ropinirole prolonged release in early stage Parkinson's disease.

AIM: This Phase IV, double-blind, randomized, parallel-group study characterized the dose-response and tolerability of fixed doses of ropinirole prolonged release (PR). PATIENTS & METHODS: Subjects with early Parkinson's disease (PD) received placebo or ropinirole PR 2, 4, 8, 12 or 24 mg once daily, up-titrated to randomized or highest tolerated dose, maintained for 4 weeks. RESULTS: The primary end point was not met (change from baseline in Unified PD Rating Scale motor score). However, because the data were not normally distributed, prespecified nonparametric analysis of covariance suggested ropinirole PR (8 and 12 mg/day) was effective in treating motor symptoms. The adverse event profile was consistent with the known safety profile of ropinirole PR. There was no impulse control disorder reported. Although a higher than previously reported rate of sudden onset of sleep events was reported, these were not dose dependent and were likely to have been influenced by the method of data collection. CONCLUSION: The adverse event profile was consistent with the known safety profile of ropinirole PR and ropinirole PR (8 or 12 mg/day) improved motor symptoms of early PD.

A randomized, fixed-dose, dose-response study of ropinirole prolonged release in advanced Parkinson's disease.

AIM: This Phase IV, double-blind, randomized, parallel-group study characterized the dose-response and tolerability of fixed doses of ropinirole prolonged release (PR) in subjects with advanced Parkinson's disease. PATIENTS & METHODS: Subjects receiving concomitant l-dopa received once-daily ropinirole PR 4, 8, 12, 16 or 24 mg, or placebo, up-titrated for 13 weeks, maintained for 4 weeks. RESULTS: At maintenance period week 4, ropinirole PR significantly reduced total awake 'Off-time' (16 mg; p = 0.027); increased absolute awake time spent 'On' without troublesome dyskinesia from baseline versus placebo (8 mg; p = 0.036); improved Unified Parkinson's Disease Rating Scale motor scores versus placebo (all doses; p = 0.005-0.016). Incidence of adverse events was similar between treatment groups; no dose-related trends were observed. CONCLUSION: Ropinirole PR (16 mg) reduced 'Off-time' with 8 mg the likely lowest maximally effective dose, and the safety profile was consistent with previous studies.

Gabapentin enacarbil and morphine administered in combination versus alone: a double-blind, randomized, pharmacokinetic, and tolerability comparison.

PURPOSE: Coadministration of morphine with oral gabapentin has been shown to increase plasma gabapentin concentrations. This study evaluated whether there was any interaction between gabapentin enacarbil (GEn), which is a prodrug of gabapentin, and morphine in terms of pharmacokinetics, pharmacodynamics, safety, and tolerability. METHODS: This randomized, double-blind, 3-treatment crossover study included nonelderly, healthy male subjects. The study subjects received (in random order and with a minimum 7-day washout between treatments) the following: morphine placebo + GEn 600 mg; morphine 60 mg + GEn 600 mg; and morphine 60 mg + GEn placebo. Morphine/morphine placebo was administered in fasted conditions, and GEn/GEn placebo was administered 2 hours later with food. The primary end points were AUC and C(max) for gabapentin, morphine, and morphine-6-glucuronide. Pharmacodynamic measures were limited to subject assessment of somnolence, dizziness, and nausea conducted by using a visual analog scale (VAS). Safety monitoring included adverse event reporting, clinical laboratory tests, vital signs, pulse oximetry, and 12-lead ECGs. FINDINGS: Of the 18 enrolled subjects (mean age, 36 years), 15 (83%) completed the study. Sixteen received GEn, 15 received morphine, and 18 received the combination. Compared with the single treatments, the 90% CIs for the ratio of the geometric means for both AUC and C(max) were all within 0.8 to 1.25, the accepted range for bioequivalence. Ratios of geometric mean (90% CIs) values were as follows: gabapentin, AUC of 1.10 (1.035-1.162) and C(max) of 1.02 (0.920-1.126); morphine, AUC of 1.06 (1.014-1.098) and C(max) of 1.05 (0.967-1.134); and morphine-6-glucuronide, AUC of 0.992 (0.929-1.058) and C(max) of 0.953 (0.855-1.062). Mean changes from predose VAS scores were generally small and suggested a slight increase in dizziness after GEn and slight increases in dizziness, somnolence, and nausea after morphine. Trends were noted suggesting slightly greater score changes from predose with the combination treatment than with either drug given alone for somnolence and dizziness. Adverse events were generally mild; there were no serious adverse events or subject withdrawals due to adverse events. Headache and nausea were among the most commonly reported events for the combination and morphine treatments (headache, 27% and 28%; nausea, 13% and 11%, respectively). There were fewer adverse events with GEn alone than with either of the combination regimens. IMPLICATIONS: No significant pharmacokinetic interaction between the 2 drugs was seen in this study. The VAS data suggest that the potential exists for increased adverse effects when GEn and morphine are coadministered. ClinicalTrials.gov identifier: NCT01476124.

Cardiac repolarization with Gabapentin enacarbil in a randomized, double-blind, placebo- and active-controlled, crossover thorough QT/QTc study in healthy adults.

BACKGROUND: Gabapentin enacarbil (GEn) is a prodrug of gabapentin and is approved in the United States in adults for the management of postherpetic neuralgia and in the United States and Japan for the treatment of moderate-to-severe primary restless legs syndrome. OBJECTIVE: This study examined the lack of effect of GEn on cardiac repolarization in accordance with International Conference on Harmonisation E14 guidance. METHODS: This was a randomized, double-blind, double-dummy, placebo- and active- controlled, crossover study in healthy adults (age range, 18-50 years). Study participants received the following in randomized order with a minimum 7-day washout period between treatments: placebo at 0 hours and GEn 1200 mg at 2 hours (GEn 1200 mg group), placebo at 0 hours and GEn 6000 mg at 2 hours (GEn 6000 mg group), placebo at 0 and 2 hours (placebo group), moxifloxacin 400 mg (active control group) at 0 hours, and placebo at 2 hours (moxifloxacin group). Dose offsetting permitted moxifloxacin to be administered in the fasted state and GEn to be administered in the fed state. Assessments included continuous ECG monitoring, pharmacokinetic parameters, and safety and tolerability profiles. The primary end point was the change from baseline in the Fridericia corrected QT interval, at each time point, for the GEn 6000 mg and placebo groups. RESULTS: Of 52 adults enrolled (mean [SD] age, 30.8 [8.55] years; 50% women), 44 adults (85%) completed the study. Forty-nine adults received GEn 1200 mg, 47 received GEn 6000 mg, 48 received placebo, and 47 received moxifloxacin. The highest estimated (upper limit of the 95% CI) model-adjusted difference in mean change from baseline in the Fridericia corrected QT interval between GEn and placebo was 3.55 (5.66) msec for 1200 mg and 1.20 (3.32) msec for 6000 mg. Assay sensitivity was confirmed with moxifloxacin 400 mg. The geometric mean (%CV) Cmax (between-subject coefficient of variation) was 7.49 (21.2) µg/mL for GEn 1200 mg, 32.46 (23.9) µg/mL for GEn 6000 mg, and 2.08 (24.5) µg/mL for moxifloxacin 400 mg. The most frequently reported adverse events with GEn 6000 mg were dizziness (30%), feeling drunk (26%), nausea (15%), headache (13%), and vomiting (13%). CONCLUSION: Single doses of GEn, up to 6000 mg, had no effect on cardiac repolarization in this thorough-QT study and are unlikely to cause clinically relevant QT prolongation in clinical use. Assay sensitivity was confirmed with moxifloxacin as an active control. ClinicalTrials.gov identifier: NCT01516372.

Pharmacokinetics, Safety, and Tolerability Following the Administration of a Single Dose of a Combination Tablet Containing Sumatriptan and Naproxen Sodium in Adolescent Patients With Migraine and in Healthy Adult Volunteers.

OBJECTIVE: The objective was to compare the pharmacokinetics of sumatriptan and naproxen in adolescent migraineurs and healthy adults after administration of sumatriptan/naproxen sodium combination tablets. DESIGN: The design was an open-label, randomized, parallel group study. Adolescent migraineurs (12-17 years) and healthy adults received 1 dose of sumatriptan/naproxen: 10 mg/60 mg, 30 mg/180 mg, or 85 mg/500 mg. Pharmacokinetic and safety assessments were conducted. RESULTS: Sumatriptan achieved Cmax rapidly (median tmax : 0.8-1.5 hours for adolescents, 0.5-2.0 hours for adults); elimination was also rapid (geometric mean t½ : <2 hours for adolescents, 1.9-2.4 hours for adults). Compared with sumatriptan, naproxen was absorbed and eliminated more slowly (median tmax : 1.0-4.0 hours for adolescents, 1.0-3.0 hours for adults; geometric mean t½ : 13.4-16.3 hours for adolescents, 14.3-16.6 hours for adults). Sumatriptan Cmax and AUC were similar for adolescents and adults for the 85 mg/500 mg dose; exposure for the 2 lower doses showed slight differences (not significant). Naproxen Cmax and AUC were comparable between the 2 groups at all doses. Increases in sumatriptan Cmax and AUC were dose proportional; for naproxen, slightly less than proportional. The tablets were generally well tolerated. CONCLUSION: Sumatriptan and naproxen pharmacokinetics were not dissimilar between adolescent migraineurs and healthy adults.