Examining the effects of intravenous oxytocin infusion on peripheral sensory afferents using microneurography technique in healthy volunteers: a triple-blind, randomized, placebo-controlled trial

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Linkopings Universitet

Participant type

Healthy volunteers

Age range

18-64 years

Gender

Male and Female

Therapeutic area

Diseases [C] - Nervous System Diseases [C10]

Trial duration

13 Oct 2025 → ongoing

Decision date (initial)

2025-04-14

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Linköping University

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Efficacy, Pharmacodynamic

To investigate effects of intravenous oxytocin in contrast to placebo on cutaneous mechanoreceptors and its interplay with acute inflammation, cognitive performances, and other subjective measures. We will address this question by measuring oxytocin effects, relative to placebo (saline), in healthy participants using MNG. The primary outcome measure will be the number of action potentials (spikes) generated by AHTMRs and ALTMRs in response to skin indentation after heat-induced experimental inflammation.

Secondary objectives 1

1. The secondary objectives include psychophysical measurements of the perception of various stimuli (before and after heat-induced inflammation), and psychophysical measurements of tactile stimulation. The secondary objectives also include measuring cognitive performance (using various tasks), exploring correlations between pain and pleasantness or cognitive function, and relationship between sex and the primary/secondary outcomes.

Conditions and MedDRA coding

Healthy participants

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 5

1. Age 18-65 years, and willing to provide informed consent
2. Good health as determined by medical history, ECG, and clinical assessment of lab tests. The final decision regarding inclusion will be according to the judgment of the lead physician.
3. 3. Abstinence from recreational/illicit or medical substances (including amphetamines, cannabis, opiates and benzodiazepines) 24 hours before and during the experiment, as determined by medical history and clinical assessment of blood samples and urine toxicology tests. Furthermore, the participant are expected to refrain from caffeine, alcohol, and nicotine for a minimum of 12 h before the experiment, based on previous recommendation (76), as well as to avoid any potential drug-drug interactions and influence on cognitive and physiological measures
4. 4. Proficiency in Swedish or English.
5. 5. Fertile females must have a negative urine pregnancy test (hCG) at the start of the study session. Females of childbearing potential who are sexually active and have not been surgically sterilized must agree to use an adequate method of birth control during the study

Exclusion criteria 15

1. 1. Hypersensitivity, allergy, or significant reaction to any ingredient of oxytocin (Oxytocin Grindeks®) or NaCl infusion (ATC code: V07AB).
2. 2. Any clinically significant medical condition as determined by interview of the research nurse and lab test performed during screening visit, or any disease, diagnosis, or condition (medical or surgical) including immunosuppression that, in the opinion of the PI, would place the subject at increased risk (active gynecologic disease in which increased tone would be detrimental e.g., uterine fibroids with ongoing bleeding), compromise the subject’s compliance with study procedures, or compromise the quality of the data.
3. 3. Women who are pregnant (positive result for urine pregnancy test at screening visit), women who are currently nursing or lactating, or women that have been pregnant within 2 years
4. 4. Subjects with neuropathy, chronic pain, diabetes mellitus, or taking benzodiazepines or pain medications on a daily basis. Subjects with current or history of ventricular tachycardia, atrial fibrillation or prolonged QT interval.
5. 5. Subjects with past or current history of hyponatremia or at risk for hyponatremia.
6. 6. Use of prescription or over-the-counter drugs that could interfere with the clinical effects of oxytocin or exacerbate side effects of oxytocin, including taking thiazide diuretics, loop diuretics, combination diuretics, lithium, carbamazepine, enalapril, Ramipril, celecoxib, temazepam, gliclazide, glimepiride, glibenclamide, glipizide, omeprazole, pantoprazole, desmopressin, SSRI’s, MAOI, the recreational drug ecstasy or CNS-active medications. Furthermore, clinically relevant CYP3A4 inhibitors (such as clarithromycin, itraconazole, ketoconazole, posaconazole, diltiazem, erythromycin, fluconazole, voriconazole, verapamil and grapefruit juice) or CYP3A4 inducers (such as phenobarbital, phenytoin, carbamazepine, rifampicin, glucocorticoids and St. John's Wort) that potentially affects the level or activity of oxytocin (77).
7. 7. Any medical condition that, in the judgment of the PI or designee and after appropriate consultation if needed, is likely to influence neuronal activities, information processing, oxytocin level/activity or somatosensation.
8. 8. Subjects with substance use disorders or any other psychiatric disorders: any current clinically significant psychiatric problems including a diagnosis of substance dependence other than nicotine (defined in DSM-5 terms as Substance Use Disorder, Moderate or Severe; (78), as assessed by PI or designee. Patients will be screened using a urine drug screening test, MMS (79), the Drug DUDIT (80), and AUDIT (81). The results and their clinical significance will ultimately be evaluated by a trained healthcare professional (nurse or physician). If indication is obtained that a clinically significant psychiatric disorder may be present, a full Mini-International Neuropsychiatric Interview (MINI) will be carried out by appropriately trained staff (82).
9. 9. Implanted medical devices such as pacemakers.
10. 10. Use of any illicit drugs (e.g. cannabis, amphetamines).
11. 11. History of psychotic experiences and familial history (first and second degree relatives) of psychosis or alcohol use disorder (83)
12. 12. Unable to provide a negative urine drug screen (including amphetamines, THC, opiates and benzodiazepines).
13. 13. Any other condition due to which, in the judgment of the PI or designee, participation in the study is not in the subject’s best interest or is unlikely to yield valid data.
14. 14. Subjects with a known latex allergy
15. 15. Subjects with previous high risk of fainting episodes

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. • Single afferent neuronal response (i.e., number of spike) of afferents to test filaments (1000 and 20 mN after heat-inflammation in AHTMRs and in LTMRs, respectively (see details under 10.2.1).

Secondary endpoints 3

1. • Psychophysics I: Psychophysical quantification of touch pleasantness
2. • Psychophysics I: Psychophysical quantification of inflammation
3. • Measuring the scores on cognitive performances (information processing speed accuracy, scores on learning and memory, and maximum scores and total scores on verbal WM) contrasting oxytocin with saline infusion

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Linkopings Universitet

Sponsor organisation

Linkopings Universitet

Address

Sandbacksgatan 7, Linkopings Domkyrkofors. Linkopings Domkyrkofors.

City

Linkoping

Postcode

582 25

Country

Sweden

Scientific contact point

Organisation

Linkopings Universitet

Contact name

Håkan Olausson

Public contact point

Organisation

Linkopings Universitet

Contact name

Håkan Olausson

Locations

1 EU/EEA country · 1 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 17 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

1 submissions — initial application plus substantial / non-substantial modifications