Trial Outcomes & Findings for Defining a PK and PD Model for Peripheral Analgesia After IV Oxytocin (NCT NCT05929339)

Last Updated: 2025-10-28

Results Overview

Verbal pain score measured at one minute intervals during the 5 minute heating of the skin at intervals up to180 minutes after the initiation of the oxytocin infusions, then at 24 hours and 5-7 days after oxytocin infusions. The verbal pain score at the 5 minute measurement is the primary pharmacodynamic outcome for the purpose of modeling the pharmacokinetic-pharmacodynamic relationship. Note that the timing of the primary outcome differs among arms. Pain intensity report will be recorded each minute during the heating of the skin to 45 - 47 degrees Celsius . Pain will be determined using a Verbal Pain scale 0-10. 0 is equivalent to NO PAIN and 10 is equivalent to THE WORST PAIN IMAGINABLE. Heating temperature will be determined according to pain rating during screening visit.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

25 participants

Primary outcome timeframe

5-7 days

Results posted on

2025-10-28

Participant Flow

Healthy participants were recruited from the community from Aug 17, 2023 through October 2, 2024 via IRB-approved advertisements and IRB-approved lists of previous participants who agreed to be contacted for future studies. They were recruited by phone and provided written informed consent at the day of the training visit.

Participant milestones

Participant milestones
Measure	Verbal Pain Score at 10 Minutes In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 10, 25, 40, 55, 70, 85, 100, 115, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.	Verbal Pain Score at 15 Minutes In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 15, 30, 45, 60, 75, 90, 105, 120, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.	Verbal Pain Score at 20 Minutes In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 20, 35, 50, 65, 80, 95, 110, 125, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.
Overall Study STARTED	8	8	9
Overall Study COMPLETED	8	8	9
Overall Study NOT COMPLETED	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Defining a PK and PD Model for Peripheral Analgesia After IV Oxytocin

Baseline characteristics by cohort

PRIMARY outcome

Timeframe: 5-7 days

Population: There was one outlier in the Verbal Pain Score at 20 Minutes group, whose data was not included in the primary analysis.

Outcome measures

Outcome measures
Measure	Verbal Pain Score at 10 Minutes n=8 Participants Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 10, 25, 40, 55, 70, 85, 100, 115, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin	Verbal Pain Score at 15 Minutes n=8 Participants Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 15, 30, 45, 60, 75, 90, 105, 120, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin	Verbal Pain Score at 20 Minutes n=9 Participants Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 20, 35, 50, 65, 80, 95, 110, 125, and 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin
Verbal Pain Score at the End of 5 Minutes of Skin Heating 10 minutes after starting oxytocin infusion (first arm only)	3.3 score on a scale Standard Deviation 0.9	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 15 minutes after starting oxytocin infusion (second arm only)	—	3.1 score on a scale Standard Deviation 0.9	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 20 minutes after starting oxytocin infusion (third arm only)	—	—	3.4 score on a scale Standard Deviation 1.9
Verbal Pain Score at the End of 5 Minutes of Skin Heating 25 minutes after starting oxytocin infusion (first arm only)	3.1 score on a scale Standard Deviation 1.3	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 30 minutes after starting oxytocin infusion (second arm only)	—	3.6 score on a scale Standard Deviation 1.3	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 35 minutes after starting oxytocin infusion (third arm only)	—	—	3.4 score on a scale Standard Deviation 2.2
Verbal Pain Score at the End of 5 Minutes of Skin Heating 40 minutes after starting oxytocin infusion (first arm only)	2.8 score on a scale Standard Deviation 1.0	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 45 minutes after starting oxytocin infusion (second arm only)	—	2.4 score on a scale Standard Deviation 1.3	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 50 minutes after starting oxytocin infusion (third arm only)	—	—	3.1 score on a scale Standard Deviation 2.2
Verbal Pain Score at the End of 5 Minutes of Skin Heating 55 minutes after starting oxytocin infusion (first arm only)	3.0 score on a scale Standard Deviation 0.9	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 60 minutes after starting oxytocin infusion (second arm only)	—	2.6 score on a scale Standard Deviation 1.0	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 65 minutes after starting oxytocin infusion (third arm only)	—	—	3.2 score on a scale Standard Deviation 2.1
Verbal Pain Score at the End of 5 Minutes of Skin Heating 70 minutes after starting oxytocin infusion (first arm only)	2.3 score on a scale Standard Deviation 1.3	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 75 minutes after starting oxytocin infusion (second arm only)	—	2.6 score on a scale Standard Deviation 1.1	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 80 minutes after starting oxytocin infusion (third arm only)	—	—	3.1 score on a scale Standard Deviation 2.2
Verbal Pain Score at the End of 5 Minutes of Skin Heating 85 minutes after starting oxytocin infusion (first arm only)	2.3 score on a scale Standard Deviation 0.9	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 90 minutes after starting oxytocin infusion (second arm only)	—	2.1 score on a scale Standard Deviation 0.9	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 95 minutes after starting oxytocin infusion (third arm only)	—	—	3.2 score on a scale Standard Deviation 2.1
Verbal Pain Score at the End of 5 Minutes of Skin Heating 100 minutes after starting oxytocin infusion (first arm only)	2.5 score on a scale Standard Deviation 1.2	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 105 minutes after starting oxytocin infusion (second arm only)	—	2.0 score on a scale Standard Deviation 0.8	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 110 minutes after starting oxytocin infusion (third arm only)	—	—	2.9 score on a scale Standard Deviation 2.3
Verbal Pain Score at the End of 5 Minutes of Skin Heating 115 minutes after starting oxytocin infusion (first arm only)	2.6 score on a scale Standard Deviation 0.5	—	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 120 minutes after starting oxytocin infusion (second arm only)	—	2.1 score on a scale Standard Deviation 1.1	—
Verbal Pain Score at the End of 5 Minutes of Skin Heating 125 minutes after starting oxytocin infusion (third arm only)	—	—	3.3 score on a scale Standard Deviation 2.5
Verbal Pain Score at the End of 5 Minutes of Skin Heating 180 minutes after starting oxytocin infusion (all arms)	2.8 score on a scale Standard Deviation 1.3	1.7 score on a scale Standard Deviation 1.7	3.5 score on a scale Standard Deviation 2.2
Verbal Pain Score at the End of 5 Minutes of Skin Heating 24 hours after starting oxytocin infusion (all arms)	3.0 score on a scale Standard Deviation 1.1	2.6 score on a scale Standard Deviation 1.4	3.7 score on a scale Standard Deviation 2.0
Verbal Pain Score at the End of 5 Minutes of Skin Heating 5-7 days after starting oxytocin infusion (all arms)	3.5 score on a scale Standard Deviation 1.4	2.9 score on a scale Standard Deviation 1.1	3.7 score on a scale Standard Deviation 1.9

Adverse Events

Verbal Pain Score at 10 Minutes

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Verbal Pain Score at 15 Minutes

Serious events: 0 serious events

Other events: 4 other events

Deaths: 0 deaths

Verbal Pain Score at 20 Minutes

Serious events: 0 serious events

Other events: 5 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Verbal Pain Score at 10 Minutes n=8 participants at risk Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 10 minutes after starting the intervention, then every 15 minutes until 115 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin	Verbal Pain Score at 15 Minutes n=8 participants at risk Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 15 minutes after starting the intervention, then every 15 minutes until 120 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin	Verbal Pain Score at 20 Minutes n=9 participants at risk Two 30 minute infusions of oxytocin, 10 IU, will be administered. The second infusion will be given 30 minutes after the completion of the first infusion. In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 20 minutes after starting the intervention, then every 15 minutes until 125 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the first oxytocin infusion. Oxytocin: Intravenous oxytocin
Vascular disorders Flushing	25.0% 2/8 • Number of events 2 • 5 to 7 days after oxytocin infusion On the day of oxytocin infusion, vital signs were recorded at intervals before and up to 180 minutes after beginning the first infusion. Subjects were observed for transient facial flushing and were queried for any adverse events. On visits 24 hr and 5 to 7 days later, subjects were queried regarding any adverse events.	50.0% 4/8 • Number of events 4 • 5 to 7 days after oxytocin infusion On the day of oxytocin infusion, vital signs were recorded at intervals before and up to 180 minutes after beginning the first infusion. Subjects were observed for transient facial flushing and were queried for any adverse events. On visits 24 hr and 5 to 7 days later, subjects were queried regarding any adverse events.	55.6% 5/9 • Number of events 5 • 5 to 7 days after oxytocin infusion On the day of oxytocin infusion, vital signs were recorded at intervals before and up to 180 minutes after beginning the first infusion. Subjects were observed for transient facial flushing and were queried for any adverse events. On visits 24 hr and 5 to 7 days later, subjects were queried regarding any adverse events.

Additional Information

James C. Eisenach, MD

Wake Forest University School of Medicine

Phone: 336716-4182

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Measure	Verbal Pain Score at 10 Minutes n=8 Participants In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 10 minutes after starting the intervention, then every 15 minutes until 115 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.	Verbal Pain Score at 15 Minutes n=8 Participants In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 15 minutes after starting the intervention, then every 15 minutes until 120 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.	Verbal Pain Score at 20 Minutes n=9 Participants In this arm the first primary outcome measure (verbal pain report at the end of 5 minutes of skin heating) is obtained at 20 minutes after starting the intervention, then every 15 minutes until 125 minutes and at 180 minutes after starting the intervention. The primary outcome is also measured on separate study visits 24 hours and between 5-7 days after starting the intervention.	Total n=25 Participants Total of all reporting groups
Age, Continuous	50 years STANDARD_DEVIATION 19 • n=5 Participants	24 years STANDARD_DEVIATION 4 • n=7 Participants	42 years STANDARD_DEVIATION 21 • n=5 Participants	38 years STANDARD_DEVIATION 19 • n=4 Participants
Sex: Female, Male Female	4 Participants n=5 Participants	4 Participants n=7 Participants	5 Participants n=5 Participants	13 Participants n=4 Participants
Sex: Female, Male Male	4 Participants n=5 Participants	4 Participants n=7 Participants	4 Participants n=5 Participants	12 Participants n=4 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	8 Participants n=5 Participants	8 Participants n=7 Participants	9 Participants n=5 Participants	25 Participants n=4 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	2 Participants n=7 Participants	1 Participants n=5 Participants	3 Participants n=4 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) White	8 Participants n=5 Participants	6 Participants n=7 Participants	8 Participants n=5 Participants	22 Participants n=4 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Region of Enrollment United States	8 participants n=5 Participants	8 participants n=7 Participants	9 participants n=5 Participants	25 participants n=4 Participants
Verbal pain score at the end of 5 minute skin heating	3.9 units on a scale STANDARD_DEVIATION 0.8 • n=5 Participants	3.9 units on a scale STANDARD_DEVIATION 0.8 • n=7 Participants	4.1 units on a scale STANDARD_DEVIATION 1.8 • n=5 Participants	4.0 units on a scale STANDARD_DEVIATION 1.2 • n=4 Participants