NCT03557008

Responses to Rabies Vaccine in Adults With or Without Antibiotics

Systems Biology of Inactivated Rabies Vaccine in Healthy Adults With or Without Use of Broad Spectrum Antibiotics

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 37 (actual)
• Sponsor: Emory University · Academic / Other
• Sex: All
• Age: 18 Years – 49 Years
• Healthy volunteers: Accepted

Summary

The use of antibiotics changes micro-organisms in the intestines which may impact the body's vaccine immune response and alter the effectiveness of the rabies vaccine. There will be two randomized groups (1:1 randomization). Group A will start taking an antibiotic regimen by mouth 3 days prior to vaccination and continue taking antibiotics the day of rabies vaccination and one day after vaccination for a total of 5 days. Group B will only receive the rabies vaccination and will not take any antibiotics. The dosage of each antibiotic is taken from their respective package inserts and does not exceed the maximum dose allowed for each antibiotic. The purpose of the study is to look at immune response after rabies vaccination with or without the use of antibiotics from day of vaccination to 28 days post vaccination in both groups.

Detailed description

Vaccination has been one of the most important and cost-effective public health interventions to provide protection against infectious diseases. Since the introduction of the first vaccine in 1796, there have been countless advances in the field. However, numerous gaps remain to be addressed. An important gap is understanding the mechanisms that lead to suboptimal immune responses to vaccination. It has been shown that the magnitude of the immune response produced by vaccines is highly variable among individuals, with both genetic and environmental factors playing an important role. More recently, emphasis is being placed on the role of the microbiota in vaccine immunogenicity. The microbiome is the collection of all microbial cells in and on the human body, with the majority being in the gastrointestinal tract. The composition of the microbiome has the ability to affect B and T cell development, which are important aspects of the adaptive immune system and major responders to vaccination. Due to this link between microbiome and the immune system, it is important to further understand the impact of the microbiome on the immune response to vaccination. This can be done using systems vaccinology, which is the application of systems biology in vaccinology to predict vaccine efficacy. The aim is to find molecular signatures, or patterns of gene expression induced after vaccination, which can be used to correlate and predict the development of protective immunity. The goal of this study is to determine whether alteration of microbiota by antibiotic exposure can negatively impact the immunogenicity of rabies vaccine, and to assess the innate and adaptive immune mechanisms responsible for that phenomenon. Half of the study participants will receive the rabies vaccine alone and half will receive the rabies vaccine along with a 5 day course of antibiotics. The primary objective of this study is to compare antibody titers 28 days after vaccination with the rabies vaccine in adults with or without use of antibiotics.

Conditions

• Rabies Human

Interventions

Type	Name	Description
BIOLOGICAL	Rabies Vaccine	A 1.0 milliliter (mL) dose of Imovax® will be given to participants on Day 0 and Day 28 of the study.
DRUG	Metronidazole	The antibiotic regimen will be given for five days beginning 3 days prior to vaccination, on the vaccination day, and one day after vaccination for a total for 5. The regimen will include 500 milligrams (mg) of Flagyl taken by mouth three times a day.
DRUG	Vancomycin	The antibiotic regimen will be given for five days beginning 3 days prior to vaccination, on the vaccination day, and one day after vaccination for a total for 5. The regimen will include 125 mg of Vancocin taken by mouth four times a day.
DRUG	Neomycin Sulfate	The antibiotic regimen will be given for five days beginning 3 days prior to vaccination, on the vaccination day, and one day after vaccination for a total for 5. The regimen will include 500 milligrams (mg) of Neomycin sulfate taken by mouth three times a day.

Timeline

• Start date: 2018-07-05
• Primary completion: 2022-06-02
• Completion: 2022-06-02
• First posted: 2018-06-14
• Last updated: 2023-06-08
• Results posted: 2023-06-08

Locations

2 sites across 1 country: United States

Regulatory

• FDA-regulated drug study