Evaluation Of The Efficacy And Safety Of Single Doses Of PF-05089771 In Patients With Primary (Inherited) Erythromelalgia (IEM)

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10, where 0= no pain and 10= worst possible pain; higher scores signify more pain. The average pain score was calculated as the mean of the pain scores recorded every 15 minutes from 0 to 4 hours post-dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 2= first time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP2 is approximately a time point 4-5 hours post-dose. The average pain score was calculated as the mean of the pain scores recorded from EP2 to 8 hours post-dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 3= second time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP3 is approximately a time point 8-9 hours post-dose. The average pain score was calculated as the mean of the pain scores recorded from EP3 to 10 hours post-dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 4= third time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP4 is approximately a time point 24-25 hours post-dose. The average pain score was calculated as the mean of the pain scores recorded from EP4 to 28 hours post-dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Maximum pain score in 4 hours period post-dosing is reported.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 2= first time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP2 is approximately a time point 4-5 hours post-dose. Maximum pain score in period from post EP2 to 8 hours post-dose is reported.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 3= second time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP3 is approximately a time point 8-9 hours post-dose. Maximum pain score in period from post EP3 to 10 hours post-dose is reported.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 4= third time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP4 is approximately a time point 24-25 hours post-dose. Maximum pain score in period from post EP4 to 28 hours post-dose is reported.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. The duration of time that participants experienced PI-NRS score greater than 5 from the 0 hours to 4 hours post-dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 2= first time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP2 is approximately a time point 4-5 hours post-dose. The duration of time that participants experienced PI-NRS score >5 from in period from post EP2 to 8 hours post-dose is reported.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 3= second time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP3 is approximately a time point 8-9 hours post-dose. The duration of time that participants experienced PI-NRS score >5 from the post EP3 to 10 hours post dose.

Participants rated severity of their pain at 11 point PI-NRS, by choosing a number between 0 and 10. Where 0= no pain and 10= worst possible pain; higher scores signify more pain. Evoked pain time point 4= third time point post-dose when pain was evoked using the participant specific heat pain stimulus. EP4 is approximately a time point 24-25 hours post-dose. The duration of time that participants experienced PI-NRS score >5 from post EP4 to 28 hours post-dose.

Participant was asked "How would you rate the study medication you received for pain?". The participant was provided the following choices as an answer: excellent=4; good=3; fair=2; poor=1. Response to this question, was participant's overall impression (global evaluation) of the study medication at 4 hour post-dose or at time of first rescue treatment or medication, which ever occurred first.

Time to rescue medication (hour) was calculated as: date/time of rescue medication minus date/time of first dose for each period. If participant who did not receive rescue medication, the time of censoring was cut off at 24 hours or the time of withdrawal, whichever was earlier. Kaplan-Meier method was used for estimation.

An AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. A treatment emergent AE was defined as an event that emerged during the treatment period that was absent before treatment, or worsened during the treatment period relative to the pretreatment state.

Laboratory abnormalities: Hemoglobin (Hgb), hematocrit, red blood cell count: less than(<)0.8*lower limit of normal(LLN), platelet: <0.5*LLN/greater than (>)1.75*upper limit of normal (ULN), white blood cell: <0.6*LLN/>1.5*ULN, lymphocyte, neutrophil (absolute, %):<0.8*LLN/>1.2*ULN, total neutrophil <0.8*LLN;basophil, eosinophil, monocyte (absolute, %):>1.2*ULN; mean corpuscular (MC) volume, mean cell hemoglobin, MC hemoglobin concentration, mean platelet volume: <0.9*LLN/>1.1*ULN; total bilirubin >1.5*ULN, aspartate aminotransferase (AT), alanine AT, gammaglutamyl transferase, alkaline phosphatase:> 3.0*ULN, total protein, albumin: <0.8*LLN/>1.2*ULN; blood urea nitrogen, creatinine:>1.3*ULN, uric acid >1.2*ULN; sodium <0.95*LLN/>1.05*ULN, potassium, chloride, calcium, magnesium, bicarbonate: <0.9*LLN/>1.1*ULN; glucose <0.6*LLN/>1.5*ULN; urine (specific gravity <1.003/>1.030, pH <4.5/>8, glucose, ketone, protein, blood/Hgb, urobilinogen, bilirubin, nitrite, leukocyte esterase >=1).

The minimum starting temperature to measure core body temperature used was 33 degree Celsius. Clinically significant changes from baseline in core body temperature was judged by investigator.

Criteria for clinically significant blood pressure abnormalities: systolic blood pressure >=30 millimetre of Mercury (mmHg) change from baseline in same posture, systolic blood pressure <90 mmHg, diastolic blood pressure >=20 mmHg change from baseline in same posture, diastolic blood pressure <50 mmHg.

Criteria for clinically significant abnormalities in ECG : PR interval >=300 millisecond (msec) and 25 percent (%) increase when baseline >200 msec, 50% increase when baseline less than or equal to (<=) 200 msec; QRS interval >=140 msec, >=50% increase from baseline; QT interval >=500 msec; QT interval corrected using the Fridericia formula (QTcF) 450 msec to <480 msec, >=480 msec, 30 to <60 msec increase from baseline, >=60 msec increase from baseline.