Trial Outcomes & Findings for The Neurobiology of Expectancy and Pain Perception (NCT NCT01575106)

Results Overview

Subjects received heat pain before and after the application of a neutral cream (told one application of neutral cream was lidocaine, one was capsaicin, and one was neutral) and rated pain intensity on a 0-20 Visual Analogue Scale (0-no pain, 20-intolerable pain). We only measure this outcome measure in session 3. The pain intensity for each cream was averaged amongst all participants for both the pre and post treatment in session 3. Subjects have up to 3 weeks to complete the 3 sessions.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

38 participants

Primary outcome timeframe

Weeks 1-3

Results posted on

2017-10-13

Participant Flow

Participant milestones

Participant milestones
Measure	Heat Pain There is only one cohort in this study. All subjects receive the same intervention, the application of heat pain using TSA or CHEPS. Heat pain applied using TSA or CHEPS: TSA-2001 Thermal Sensory Analyzer (Medoc LTD Advanced Medical Systems) or the Pathway Medoc (CHEPS model, Contact Heat-Evoked Potential Stimulator, Medoc LTD Advanced Medical Systems)
Overall Study STARTED	38
Overall Study COMPLETED	24
Overall Study NOT COMPLETED	14

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Neurobiology of Expectancy and Pain Perception

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Heat Pain n=24 Participants There is only one cohort in this study. All subjects receive the same intervention, the application of heat pain using TSA or CHEPS. Heat pain applied using TSA or CHEPS: TSA-2001 Thermal Sensory Analyzer (Medoc LTD Advanced Medical Systems) or the Pathway Medoc (CHEPS model, Contact Heat-Evoked Potential Stimulator, Medoc LTD Advanced Medical Systems)
Age, Continuous	26.5 years STANDARD_DEVIATION 6.7 • n=93 Participants
Sex: Female, Male Female	11 Participants n=93 Participants
Sex: Female, Male Male	13 Participants n=93 Participants

PRIMARY outcome

Timeframe: Weeks 1-3

Subjects received heat pain before and after the application of a neutral cream (told one application of neutral cream was lidocaine, one was capsaicin, and one was neutral) and rated pain intensity on a 0-20 Visual Analogue Scale (0-no pain, 20-intolerable pain). We only measure this outcome measure in session 3. The pain intensity for each cream was averaged amongst all participants for both the pre and post treatment in session 3. Subjects have up to 3 weeks to complete the 3 sessions.

Outcome measures

Outcome measures
Measure	Heat Pain n=24 Participants There is only one cohort in this study. All subjects receive the same intervention, the application of heat pain using TSA or CHEPS. Heat pain applied using TSA or CHEPS: TSA-2001 Thermal Sensory Analyzer (Medoc LTD Advanced Medical Systems) or the Pathway Medoc (CHEPS model, Contact Heat-Evoked Potential Stimulator, Medoc LTD Advanced Medical Systems)
Subjective Response to Pain (0-20 Visual Analogue Scale) Pre-treatment placebo Lidocaine	10.7 units on a scale Standard Error 2.4
Subjective Response to Pain (0-20 Visual Analogue Scale) Pre-treatment placebo capsaicin	11 units on a scale Standard Error 1.8
Subjective Response to Pain (0-20 Visual Analogue Scale) Pre-treatment neutral	11.2 units on a scale Standard Error 2.0
Subjective Response to Pain (0-20 Visual Analogue Scale) Post-treatment placebo lidocaine	8.1 units on a scale Standard Error 3
Subjective Response to Pain (0-20 Visual Analogue Scale) Post-treatment placebo capsaicin	12.2 units on a scale Standard Error 2.6
Subjective Response to Pain (0-20 Visual Analogue Scale) Post-treatment neutral	10.8 units on a scale Standard Error 2.3

PRIMARY outcome

Timeframe: Week 4

Population: The neutral cream is omitted from the data table below because we were only concerned about the direct comparison between positive expectancy ("Lidocaine") and negative expectancy ("Capsaicin") conditions. Data were only collected for the Lidocaine and Capsaicin creams.

We used fMRI to investigate the signal changes associated with administration of identical pain stimuli before (pre) and after the treatment (post) with different creams in session 3. It is important to note that the subjects had multiple weeks to complete the study, but this measure was only taken during one session. The change was calculated from two time points as the value at the later time point (post treatment) minus the value at the earlier time point (pre treatment).

Outcome measures

Outcome measures
Measure	Heat Pain n=24 Participants There is only one cohort in this study. All subjects receive the same intervention, the application of heat pain using TSA or CHEPS. Heat pain applied using TSA or CHEPS: TSA-2001 Thermal Sensory Analyzer (Medoc LTD Advanced Medical Systems) or the Pathway Medoc (CHEPS model, Contact Heat-Evoked Potential Stimulator, Medoc LTD Advanced Medical Systems)
fMRI Signal Changes in the Dorsal Anterior Cingulate Cortex Lidocaine	0.2 Post-Pre treatment peak beta Standard Deviation 0.18
fMRI Signal Changes in the Dorsal Anterior Cingulate Cortex Capsaicin	0.3 Post-Pre treatment peak beta Standard Deviation 0.3

Adverse Events

Heat Pain

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Cream

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Heat Pain n=38 participants at risk All subjects receive the same intervention, the application of heat pain using TSA or CHEPS. Heat pain applied using TSA or CHEPS: TSA-2001 Thermal Sensory Analyzer (Medoc LTD Advanced Medical Systems) or the Pathway Medoc (CHEPS model, Contact Heat-Evoked Potential Stimulator, Medoc LTD Advanced Medical Systems)	Cream n=38 participants at risk All subjects were told they would receive lidocaine, capsaicin, and neutral cream on their forearm, but in reality they only received neutral cream (regular moisturizing lotion).
Skin and subcutaneous tissue disorders Skin and tissue disorders	2.6% 1/38	0.00% 0/38

Additional Information

Jian Kong

Massachusetts General Hospital

Phone: 617-726-7893

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place