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Clinical Trial Details — Status: Completed

Administrative data

NCT number NCT00991276
Other study ID # A0081185
Secondary ID
Status Completed
Phase Phase 3
First received
Last updated
Start date December 2009
Est. completion date June 2011

Study information

Verified date September 2012
Source Pfizer
Contact n/a
Is FDA regulated No
Health authority
Study type Interventional

Clinical Trial Summary

The purpose of this study is to assess the efficacy and safety of pregabalin and pramipexole versus placebo in the treatment of restless legs syndrome and associated sleep disturbance.


Recruitment information / eligibility

Status Completed
Enrollment 85
Est. completion date June 2011
Est. primary completion date June 2011
Accepts healthy volunteers No
Gender All
Age group 18 Years and older
Eligibility Inclusion Criteria: - Diagnosis of restless legs syndrome with a total score of 15 or more points on the International RLS rating scale (IRLS). - RLS symptoms interfering with sleep on 3 or more nights per week for at least 6 months. - PSG confirmation of WASO of at least 60 min, PLMI of 10 or more, and total sleep time of at least 3 hrs and less than 6.5 hrs. Exclusion Criteria: - Secondary RLS. - Daytime RLS symptoms requiring treatment. - Primary sleep disorder. - Sleep apnea. - Night or shift work. - Concurrent medical disorder that could interfere with efficacy assessment or present a safety concern. - Pregnant or lactating women. - Women of child-bearing potential not using acceptable method of birth control. - Use of prohibited medication.

Study Design


Related Conditions & MeSH terms


Intervention

Drug:
pregabalin
capsules; 300 mg once-per-day; 4 weeks of treatment
placebo
capsules; 0 mg once-per-day; 4 weeks of treatment
pramipexole
capsules; 0.5 mg once-per-day; 4 weeks of treatment

Locations

Country Name City State
United States Pfizer Investigational Site Atlanta Georgia
United States Pfizer Investigational Site Aurora Colorado
United States Pfizer Investigational Site Austin Texas
United States Pfizer Investigational Site Austin Texas
United States Pfizer Investigational Site Baton Rouge Louisiana
United States Pfizer Investigational Site Brighton Massachusetts
United States Pfizer Investigational Site Burlingame California
United States Pfizer Investigational Site Chevy Chase Maryland
United States Pfizer Investigational Site Cincinnati Ohio
United States Pfizer Investigational Site Clarks Summit Pennsylvania
United States Pfizer Investigational Site Columbia South Carolina
United States Pfizer Investigational Site Crestview Hills Kentucky
United States Pfizer Investigational Site Dallas Texas
United States Pfizer Investigational Site Dublin Ohio
United States Pfizer Investigational Site Hallandale Beach Florida
United States Pfizer Investigational Site Hickory North Carolina
United States Pfizer Investigational Site Jasper Alabama
United States Pfizer Investigational Site Kalamazoo Michigan
United States Pfizer Investigational Site Lafayette Hill Pennsylvania
United States Pfizer Investigational Site Lexington Kentucky
United States Pfizer Investigational Site Little Rock Arkansas
United States Pfizer Investigational Site Little Rock Arkansas
United States Pfizer Investigational Site Macon Georgia
United States Pfizer Investigational Site Miami Florida
United States Pfizer Investigational Site Middleburg Heights Ohio
United States Pfizer Investigational Site New York New York
United States Pfizer Investigational Site Oklahoma City Oklahoma
United States Pfizer Investigational Site Overland Park Kansas
United States Pfizer Investigational Site Pasadena California
United States Pfizer Investigational Site Pembroke Pines Florida
United States Pfizer Investigational Site Phoenix Arizona
United States Pfizer Investigational Site Portage Michigan
United States Pfizer Investigational Site Raleigh North Carolina
United States Pfizer Investigational Site Redlands California
United States Pfizer Investigational Site San Diego California
United States Pfizer Investigational Site San Diego California
United States Pfizer Investigational Site Santa Ana California
United States Pfizer Investigational Site Santa Monica California
United States Pfizer Investigational Site Spring Hill Florida
United States Pfizer Investigational Site Tucson Arizona
United States Pfizer Investigational Site Winston-Salem North Carolina

Sponsors (1)

Lead Sponsor Collaborator
Pfizer's Upjohn has merged with Mylan to form Viatris Inc.

Country where clinical trial is conducted

United States, 

Outcome

Type Measure Description Time frame Safety issue
Primary Wake After Sleep Onset (WASO) WASO as determined by Polysomnography (PSG) was time spent awake from sleep onset to final awakening. WASO= Wake Time During Sleep [WTDS] epochs + Wake Time After Sleep [WTAS] epochs)/2. WTDS: number of wake epochs (30 seconds of PSG recording) after onset of persistent sleep and prior to final awakening or end of 8-hour recording/2 and WTAS: number of wake epochs after final awakening until end of the 8-hour recording/2. WASO was measured on 2 consecutive days within a period. Arithmetic mean of WASO of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or Early Termination (ET)
Secondary Periodic Limb Movement Arousal Index (PLMAI) PLMAI, as determined by PSG was number of periodic limb movements leading to arousal per hour (per hour of Total Sleep Time [TST]). Arithmetic mean of PLMAI of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Subjective Total Sleep Time (sTST) sTST as derived from Subjective Sleep Questionnaire (SSQ), a participant reported subjective estimate of the total amount of time the participant was asleep after lights out until final awakening. Completed by the participant 30 minutes after waking; recall period is the night before. Arithmetic mean of sTST of each participant for all periods was taken prior to employing linear mixed model. Week 3 and Week 5 of Each Intervention Period or ET
Secondary Minutes of Stage N1, N2, N3 and R Sleep Minutes of Stage 1 Non-Rapid Eye Movement (Non-REM) sleep (Stage N1), Stage 2 Non-REM sleep (Stage N2), Stage 3 Non-REM sleep (Stage N3) or Slow Wave Sleep (SWS) and Stage REM (Stage R) sleep, as determined by PSG were calculated as total number of Stage N1 30-second (30-sec) epochs divided by 2, total number of Stage N2 30-sec epochs divided by 2, total number of Stage N3 30-sec epochs divided by 2 and total number of Stage R 30-sec epochs divided by 2 respectively. Arithmetic mean of minutes of stage N1, N2, N3 and R sleep of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Number of Awakenings of at Least 1 Epoch After Sleep Onset (NAASO1) NAASO1, as determined by PSG, was the number of times there was a wake period of at least 1 epoch from the onset of persistent sleep to light on. Each entry to be counted must be separated by a Stage 2 Non-REM [Stage N2] 30-second (30-sec) epoch, Stage 3 Non-REM [Stage N3] 30-sec epoch, or stage rapid eye movement [stage R] 30-sec epoch. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period. Arithmetic mean of NAASO1 of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Restless Legs Syndrome-Next Day Impact (RLS-NDI) RLS-NDI:participant-rated instrument to assess daytime performance and participant's previous night's sleep, consists of 14 items encompassing 5 domains:tiredness;emotional functioning;social functioning;cognitive functioning;activities of daily living and 1 global item for overall well-being. Each item: 0-10 scale; 0=Not at all; 10=Extremely. Total score: sum of scores from question 1-14 (question 10, 11: scores reversed). Total score range: 0-140; higher scores: more severe impact. Arithmetic mean of RLS-NDI of each participant for all periods was taken prior to employing linear mixed model. Week 3 and Week 5 of Each Intervention Period or ET
Secondary Periodic Limb Movement Index (PLMI) PLMI, as determined by PSG was number of periodic limb movements per hour based on time in bed (TIB). Arithmetic mean of PLMI of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Periodic Limb Movement in Sleep Index (PLMSI) PLMSI, as determined by PSG was number of periodic limb movements in sleep per hour based on TST. Arithmetic mean of PLMSI of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Number of Awakenings of at Least 2 Epochs After Sleep Onset (NAASO2) NAASO2, as determined by PSG, was the number of times there was a wake period of at least 2 30-sec epochs from the onset of persistent sleep to light on. Each entry to be counted must be separated by a Stage N2 30-sec epoch, Stage N3 30-sec epoch, or Stage R 30-sec epoch. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period. Arithmetic mean of NAASO2 of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Number of Arousals (NASO) NASO, as determined by PSG, was calculated as number of times there is a shift from a stage N2 to N3 or R 30-sec epoch to a stage N1 30-sec epoch from the onset of persistent sleep to light on. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period. Arithmetic mean of NASO of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Arousal Index (NASOI) Arousal index, as determined by PSG, was NASO per hours of sleep from the onset of persistent sleep to light on. Arithmetic mean of NASOI of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary International Restless Legs Syndrome Study Group Rating Scale (IRLS) IRLS: psychometrically; clinically valid; clinician-administered instrument assesses severity of RLS. RLS symptom severity and impact on daily living comprise of 10 items giving 2 subscale scores and 1 global score. Subscale scores: symptom severity(6 items) and impact on daily living(3 items), item 3 loaded equally on both subscales. Global score calculated from 10 items. Score of all items range from 0-4, total score range:0-40. Lower scores: lower severity and better quality of life. Arithmetic mean of IRLS of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Percentage of Participants With Response to Clinical Global Impression - Improvement (CGI-I) Scale CGI-I: 7-point clinician rated scale to assess improvement in disease condition as compared to the start of the study medication (baseline), ranging from 1 (very much improved) to 7 (very much worse). Improvement is defined as a score of 1 (very much improved) or 2 (much improved). Higher score = more affected. Baseline, Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Latency to Stage R Sleep (LREM) LREM, as determined by PSG, was number of non-wake epochs from the beginning of the recording to the first occurrence of Stage R sleep divided by 2. Arithmetic mean of LREM of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Latency to Persistent Sleep (LPS) LPS, as determined by PSG, was number of epochs from the beginning of the recording ("lights-out") to the start of the first 20 consecutive non-wake epochs (10 minutes of persistent sleep) divided by 2. Arithmetic mean of LPS of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Wake Time During Sleep (WTDS) WTDS, as determined by PSG, was the number of wake (30-sec) epochs after the onset of persistent sleep and prior to the final awakening or at the end of 8-hour recording. WTDS was the sum of 2 consecutive days of recordings divided by 2 at the end of each intervention period. Arithmetic mean of WTDS of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Wake Time After Sleep (WTAS) WTAS, as determined by PSG, was the number of wake (30-sec) epochs after the final awakening until the end of the 8-hour recording. WTAS was the sum of 2 consecutive days of recordings divided by 2 at the end of each intervention period. Arithmetic mean of WTAS of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Total Sleep Time (TST) TST, as determined by PSG, was the number of non-wake (30-sec) epochs from the beginning of recording to the end of the recording. TST was the sum of 2 consecutive days of recording divided by 2 at the end of each intervention period. Arithmetic mean of TST of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Sleep Efficiency (SE) SE, as determined by PSG, was the TST divided by the time in bed (TIB)(both in minutes), multiplied by 100. Sum of 2 consecutive days of recording divided by 2 at the end of each intervention period. Arithmetic mean of SE of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Wake After Sleep Onset (WASO) WASO, as determined by PSG was time spent awake from sleep onset to final awakening. WASO = (sum of WTDS 30-sec epochs and WTAS 30-sec epochs)/2, measured on 2 consecutive days at end of each intervention period by each individual hour (8 hours total) and each individual quarter of night (eight hours in 2 hour increments). Arithmetic mean of WASO of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Number of Awakenings of at Least 1 Epoch After Sleep Onset (NAASO1) NAASO1, as determined by PSG, was the number of times there was a wake period of at least 1 30-sec epoch from the onset of persistent sleep to light on. Each entry to be counted must be separated by a Stage N2 30-sec epoch, Stage N3 30-sec epoch, or Stage R 30-sec epoch. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period by each individual hour (8 hours total) and each individual quarter of the night (eight hours in 2 hour increments). Arithmetic mean of NAASO1 of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Number of Awakenings of at Least 2 Epoch After Sleep Onset (NAASO2) NAASO2, as determined by PSG, was the number of times there was a wake period of at least 2 30-sec epochs from the onset of persistent sleep to light on. Each entry to be counted must be separated by a Stage N2 30-sec epoch, Stage N3 30-sec epoch, or Stage R 30-sec epoch. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period by each individual hour (8 hours total) and each individual quarter of the night (eight hours in 2 hour increments). Arithmetic mean of NAASO2 of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Number of Arousals (NASO) NASO, as determined by PSG was the number of times there is a shift from a stage N2 to N3 or R 30-sec epoch to a stage N1 30-sec epoch from the onset of persistent sleep to light on. The sum of 2 consecutive days of recording was divided by 2 at the end of each intervention period by each individual hour (8 hours total) and each individual quarter of the night (eight hours in 2 hour increments). Arithmetic mean of NASO for each participant at each period was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Periodic Limb Movement (PLM) PLM, as determined by PSG was number of periodic limb movements based on time in bed (TIB). Calculated at each individual hour (8 hours total) and each individual quarter of the night (eight hours in 2 hour increments). Arithmetic mean of PLM of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Hourly and Quarterly Assessment of Sleep Efficiency (SE) SE, as determined by PSG, was the TST divided by the time in bed (TIB)(both in minutes), multiplied by 100. Sum of 2 consecutive days of recording divided by 2 at the end of each intervention period by each individual hour (8 hours total) and each individual quarter of the night (eight hours in 2 hour increments). Arithmetic mean for SE of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Subjective Sleep Questionnaire (SSQ): Number of Awakenings Subscale SSQ: participant-rated instrument to assess sleep behavior; measures sleep quantity, quality. Comprised of 5 items giving 5 subscale scores: latency, hours of sleep, number of awakenings, total wake time after sleep onset, quality of sleep. This (1 item) subscale: numerical rating completed by participant 30 minutes after waking; recall period: night before. Range: 0 awakenings to 30 awakenings. Lower value indicates better quality of sleep. Arithmetic mean of this subscale score of each participant for all periods was taken prior to employing linear mixed model. Results of hours of sleep subscale reported as sTST. Week 3 and Week 5 of Each Intervention Period or ET
Secondary Subjective Sleep Questionnaire (SSQ): Total Wake Time After Sleep Onset Subscale SSQ: participant-rated instrument to assess sleep behavior; measures sleep quantity, quality. Comprised of 5 items yielding 5 subscale scores: latency, hours of sleep, number of awakenings, total wake time after sleep onset, quality of sleep. This 1 item subscale (in minutes): numerical rating completed by participant 30 minutes after waking; recall period: night before. Range: 0-1440 minutes. Lower value: better sleep. Arithmetic mean of this subscale score of each participant for all periods was taken prior to employing linear mixed model. Results of hours of sleep subscale reported as sTST. Week 3 and Week 5 of each intervention period or ET
Secondary Subjective Sleep Questionnaire (SSQ): Quality of Sleep Subscale SSQ: participant-rated instrument to assess sleep behavior; measures sleep quantity, quality. Comprised of 5 items yielding 5 subscale scores: latency, hours of sleep, number of awakenings, total wake time after sleep onset, quality of sleep. This 1 item subscale: numerical rating completed by participant 30 minutes after waking; recall period: night before, Range: 0 to 100, higher score: better quality of sleep. Arithmetic mean of this subscale score of each participant for all periods was taken prior to employing linear mixed model. Results of hours of sleep subscale reported as sTST. Week 3 and Week 5 of each intervention period or ET
Secondary Subjective Sleep Questionnaire (SSQ): Latency Subscale SSQ: participant-rated instrument assesses sleep behavior; measures sleep quantity, quality. Comprised of 5 items giving 5 subscale scores: latency, hours of sleep, number of awakenings, total wake time after sleep onset, quality of sleep. Latency (time to fall asleep [in minutes]): numerical rating completed by participant 30 minutes after waking; recall period: night before. Range: 0 - 840 minutes, lower value: better sleep. Arithmetic mean of subscale score of each participant for all periods was taken prior to employing linear mixed model. Hours of sleep subscale results reported as sTST. Week 3 and Week 5 of each intervention period or ET
Secondary Medical Outcomes Study - Sleep Scale (MOS-SS) MOS-SS:Participant rated instrument, assesses sleep quantity, quality;with 12 items(7 subscale scores:sleep disturbance, snoring, awakening short of breath/with headache, sleep adequacy, somnolence, sleep quantity, optimal sleep;2 composite index scores:sleep problems Index I, II). Subscale scores total range:0-100(except sleep quantity[range 0-24 hours], optimal sleep[range 0-1: 0= <7 or >8 hours;1=7/8 hours]). Higher scores=poorer sleep outcomes(except sleep quantity, adequacy). Arithmetic mean of MOS-SS scores of each participant for all periods was taken before linear mixed model analysis. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
Secondary Restless Leg Syndrome - Quality of Life Scale (RLS-QoL) RLS-QoL: psychometrically and clinically valid and reliable participant-rated instrument, assesses impact of RLS on participant quality of life. Specifically, it assessed effects of RLS on health status function (symptom severity, daily activity, social functioning, sleep, concentrating and decision making, travelling, sexual activity, and work) giving a summary score ranging from 0-100. Higher scores reflect better quality of life. Recall period: 1 week prior to assessment. Arithmetic mean of RLS-QoL score of each participant for all periods was taken prior to employing linear mixed model. Week 5 (End of Intervention Period 1), Week 11 (End of Intervention Period 2) and Week 17 (End of Intervention Period 3) or ET
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