Efficacy Of Pregabalin In Subjects With Post-Stroke Central Neuropathic Pain

Weekly mean pain score measured by DPRS: subject rated 11-point numeric scale ranging from 0 (no pain) to 10 (worst possible pain) during past 24-hour period. Higher score indicates greater level of pain. Self-assessment performed daily on awakening prior to taking study medication.

30% Responder Yes = number of subjects with 30% reduction in mean pain score from baseline to observation; 30% reduction calculated as [(T minus B) divided by B multiplied by 100] < = negative 30. T = endpoint mean pain score (obtained from last 7 available scores from DPRS); B = baseline mean pain score (obtained from average of last 7 daily scores from DPRS). 30% Responder No indicates number of subjects that did not reach 30% reduction in mean pain score.

50% Responder Yes = number of subjects with 50% reduction in mean pain score from baseline to observation; 50% reduction calculated as [(T minus B) divided by B multiplied by 100] < = negative 50. T = endpoint mean pain score (obtained from last 7 available scores from DPRS); B = baseline mean pain score (obtained from average of last 7 daily scores from DPRS). 50% Responder No indicates number of subjects that did not reach 50% reduction in mean pain score.

DSIS: subject rated 11-point numeric scale ranging from 0 (pain does not interfere with sleep) to 10 (pain completely interferes with sleep) during past 24-hour period. Higher score indicates a greater level of sleep disturbance. Self-assessment performed daily on awakening prior to taking study medication. Endpoint calculated as mean of last 7 available scores.

SF-MPQ Part B VAS consists of a line 0 to 100 millimeters (mm) in length; range is (no pain) to 100 mm (worst possible pain). Subjects placed a mark indicating the intensity of their pain. Distance from left-hand end of line was measured and entered on Case Report Form (CRF) as score in mm. Higher score indicates greater level of pain.

NPSI: subject rated questionnaire to evaluate different symptoms of neuropathic pain (dimensions: burning [superficial] spontaneous pain, pressing [deep] spontaneous pain, paroxysmal pain, evoked pain, and paresthesia/dyesthesia [P/D]). Includes 10 descriptors quantified on a 0 (no symptoms) to 10 (worst symptoms imaginable) and 2 temporal items assessing duration of spontaneous ongoing and paroxysmal pain. Questionnaire generates a score in each of the relevant dimensions and a total score (0 to 100). Higher score indicates a greater intensity of pain.

MOS: subject rated questionnaire to assess sleep quality and quantity. Consists of a 9-item overall sleep problems index (length of time to fall asleep, how many hours of sleep each night during past 4 weeks); 7 subscales rated 1 (all the time) to 6 (none of the time): sleep disturbance, snoring, awaken short of breath (SOB) or with a headache, somnolence adequacy, and sleep quantity. Scores are transformed (actual raw score minus lowest possible score divided by possible raw score range multiplied by 100); total score range = 0 to 100; higher score indicates greater intensity of attribute.

MOS: subject rated questionnaire to assess sleep quality and quantity. Optimal sleep component is derived from Sleep Quantity average hours of sleep each night during the past 4 weeks. Number of subjects with response = YES if sleep quantity is 7 or 8 hours per night or response = NO if sleep quantity is < 7 hours per night.

HADS is subject rated questionnaire with 2 subscales. HADS-A assesses state of generalized anxiety (anxious mood, restlessness, anxious thoughts, panic attacks); HADS-D assesses state of lost interest and diminished pleasure response (lowering of hedonic tone). Each subscale comprised of 7 items with range 0 (no presence of anxiety or depression) to 3 (severe feeling of anxiety or depression). Total score 0 to 21 for each subscale; higher score indicates greater severity of anxiety and depression symptoms.

EQ-5D: subject rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (eg, "confined to bed"). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in a total score range -0.594 to 1.000; higher score indicates a better health state.

EQ-5D: subject rated questionnaire to assess health-related quality of life in terms of a single index value. The VAS component rates current health state on a scale from 0 (worst imaginable health state) to 100 (best imaginable health state); higher scores indicate a better health state.

PGIC: subject rated instrument to measure subject's change in overall status on a 7-point scale; range from 1 (very much improved) to 7 (very much worse).

CGIC: clinician rated instrument that measures change in a subject's ovall status on a 7-point scale; range from 1 (very much improved) to 7 (very much worse).

QANeP: assessment of sensory threshold: subject responds "yes" when monofilament stimulus is felt on area of maximum pain: 1 (lowest/softest 0.07 gram [g]) to 6 (highest 300 g) or 7 (not perceived); rated by lowest/softest filament felt when in contact with the skin. Summarized as change from baseline (mean at observation minus mean at baseline).

Subject rated pain scale: static mechanical allodynia (SMA) gentle constant mechanical pressure; dynamic mechanical allodynia (DMA) gentle stroking with foam brush; punctate hyperalgesia (PH) pinprick; cold allodynia (CA) touch with cool metal rod 13-17° celsius (C); cold hyperalgesia (CH) touch with cold metal rod 4° C; temporal summation to tactile stimuli (TSTS) repeated touching/tapping. 11-point numeric scale; range 0 (no pain) to 10 (worst possible pain). Reference area=mirror image of pain site (test area). Summarized as change from baseline (mean at observation minus mean at baseline).