Evaluations were completed at 1-minute intervals for the first 5 minutes to capture onset of anesthesia. Starting at 5 minutes after drug administration, the PPT was done at 5 minute intervals up to the one hour time point. If there was no indication of anesthesia by 10 minutes, the subject was considered a treatment failure and the assessment of PPT was discontinued. In addition, once onset of anesthesia had occurred, if there was no longer any anesthesia at two consecutive evaluation time points from 10 minutes onward, the assessment of PPT was discontinued.

The PPT was assessed using a 90-mm, 26-gauge pencil-point spinal needle. At screening, 3 pin pricks were performed on each cheek. Pin pricks were assessed using a 0 (no pain) to 10 (severe pain) Numerical Rating Scale (NRS). In order to be eligible for the study, for each cheek, subjects must have had a minimum score of "3" for the last 2 pin pricks, and one of those scores had to be "4" or higher.

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Starting at 5 minutes after drug administration, the QST was done at 5 minute intervals up to the one hour time point. If there was no indication of anesthesia by 10 minutes, the subject was considered a treatment failure and the assessment of PPT was discontinued. In addition, once onset of anesthesia had occurred, if there was no longer any anesthesia at two consecutive evaluation time points from 10 minutes onward, the assessment of QST was discontinued.

The heat stimuli were delivered in 3 repetitions, with inter-stimulus intervals of 30s. The basal thermode temperature was set at a comfortable 35ºC. The rate at which the thermode heated up was set at 0.5ºC/s, while the rate at which it cooled down was set at 8ºC/s. The maximum thermode temperature was set at 51ºC. Heat sensation threshold was defined as the temperature at which the subjects first felt tingling, warmth, heat, or pain.

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that. Duration of effect was defined as the time (in minutes) from onset to treatment failure (i.e., for PPT, an assessment of "Same/More" pain, and for QST, the average heat temperature was greater than the average heat temperature at Baseline (non-treated cheek), up to the 60-minute time point (at two consecutive time points).

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that. Duration of effect was defined as the time (in minutes) from onset to treatment failure (i.e., for PPT, an assessment of "Same/More" pain, and for QST, the average heat temperature was greater than the average heat temperature at Baseline (non-treated cheek), up to the 60-minute time point (at two consecutive time points).

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

Modified Intent-to-Treat (mITT) population: all randomized subjects who, as documented prior to the breaking of the study blind: (1) met all the inclusion and exclusion criteria and; (2) either completed the two 60 minute test sessions or returned to baseline values in all evaluation tests.

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

Some treatment response data was missing or lost or an invalid value was recorded

Assessments will be made over a period of one hour, with assessments at 1 minute intervals for the first 5 minutes and then every 5 minutes after that.

A baseline measure was lost/missing for one treatment so the response could not be calculated.