Health TrialsbyHealthPanel

Inflammatory Challenge and Fear

ConditionPosttraumatic Stress Disorder (PTSD)
Trial statusRecruiting
Trial phasePhase 1
Trial typeInterventional
Biological sexAll
Age18-65
SponsorUniversity of California, San Francisco

About this trial

The goal of this study is to learn if short-term changes in the immune system alter how we process information and experience fear. The main questions it aims to answer are:

Do people who receive typhoid vaccine respond differently than those who receive a placebo saline vaccine? Do people who receive typhoid vaccine experience changes in how they think and feel?

Participants will:

Attend four appointments at the San Francisco VA Health Care System;

Receive typhoid vaccine or placebo at one of the visits;

Have their physiological responding measured while listening to sounds;

Complete questionnaires and psychological tests.

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Aged 18-65 years old

Trauma Exposed

Current PTSD/No history of PTSD

Disqualifiers

Contraindications to typhoid vaccine

Conditions associated with inflammation

Pregnancy or plans to become pregnant in next three months

Trial design

Design model

Parallel

Treatments tested in this trial

  • Typhoid VI Polysaccharide Vaccine Injectable Solution

    Biological/Vaccine

    Salmonella typhi capsular polysaccharide vaccine (Typhoid Vi Polysaccharide Vaccine): Each dose of 0.5ml Salmonella typhi capsular polysaccharide vaccine (Sanofi Pasteur, SA) is formulated to contain 25μg of purified Vi polysaccharide in a colorless isotonic phosphate buffered saline (pH 7±0.3), 4.150mg of sodium chloride, 0.065mg of disodium phosphate, 0.023mg of monosodium phosphate and 0.5ml of sterile water for injection. It is indicated for use by humans aged 2 years and older for protection against typhoid fever.

  • Saline Placebo (0.5mL injection)

    Other intervention

    The placebo injection will consist of 0.5mL of saline.

Treatment groups

288 Participants
are divided into 2 treatment groups
Group A: Polysaccharide typhoid vaccineExperimental treatment 1 intervention
Group B: Saline Placebo ArmPlacebo comparator 1 intervention

Trial outcomes

Primary outcomes

1

Skin conductance response (SCR)

Skin conductance level (SCL)will be sampled at 1000 Hz beginning 2 s prior to the conditioned stimulus (CS) onset and continuing until 6 s following CS offset. The skin conductance response (SCR) score for each CS interval will be obtained by subtracting the mean SCL for the 2 s preceding CS onset from the peak during the 8 s CS interval.

Time frame
SCR will be assessed at baseline, 4.5 hours, and one week after vaccine/placebo.

Secondary outcomes

1

Heart rate

HR will be calculated by subtracting average HR of every 0.5 s interval during 6 s before CS (baseline) from peak HR during 0.5 s interval of 8 s after CS onset (response).

Time frame
HR will be assessed at baseline, 4.5 hours, and one week after vaccine/placebo.
2

Eyeblink electromyography (EMG)

EMG will be calculated by subtracting the mean signal amplitude during 2 s preceding CS onset (baseline) from the peak during the 8 s CS interval (response).

Time frame
Eyeblink EMG will be assessed at baseline, 4.5 hours, and one week after vaccine/placebo.

Other outcomes

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

University of California, San Francisco

Lead sponsor

National Institute of Mental Health (NIMH)

Collaborator

Northern California Institute of Research and Education

Collaborator

San Francisco Veterans Affairs Medical Center

Collaborator

Source ClinicalTrials.gov
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