This trial is active, not recruiting.

Condition healthy
Sponsor Uniformed Services University of the Health Sciences
Collaborator National Institute of Allergy and Infectious Diseases (NIAID)
Start date October 2010
End date July 2014
Trial size 68 participants
Trial identifier NCT01289977, G183ZU, Y1-AI-0744-01


Sand flies can carry the infection leishmaniasis (a parasite). The purpose of this study is to evaluate the human immune response to uninfected laboratory raised sand fly bites and select from the immune response to sand fly saliva, possible substances to use for a future vaccine to protect against the parasite leishmaniasis.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Observational model cohort
Time perspective prospective
Those in the Phlebotomus group will have exposure to P. duboscqui sand fly
Those placed in this group will receive exposure to L. longipalpis sand fly bites.

Primary Outcomes

Human Th1 immune response to specific sand fly salivary proteins
time frame: 6-18 months

Eligibility Criteria

Male or female participants from 18 years up to 50 years old.

Inclusion Criteria: - Age 18-50 - Plans to remain in DC area for at least one year - willingness to participate in all study procedures - general good health - military health care beneficiary - able to provide informed consent Exclusion Criteria: - Prior travel to geographic areas where leishmania transmitting sand flies are common - positive antibody to sand fly saliva on screening blood test - pregnancy - elevated serum IgE - history of chronic medical illness - adult history of treatment requiring anemia - large reactions to insect bites - history of multiple vasovagal reactions to phlebotomy - difficult venous access for phlebotomy - Taking medications that could interfere with immune responses

Additional Information

Official title Immune Responses After Human Subject Challenge With Sand Fly Bites: Exploratory Study for Selection of Potential Leishmania Vaccine Antigen Candidates
Principal investigator Naomi E Aronson, MD
Description Based on travel history and possible exposure, subjects were entered into one of 2 arms, Ph. dubosqui or Lu. lutzomyia controlled sand fly repeated feedings. At baseline a pheresis was done to collect baseline cells. Subjects received sand fly bites on a q2 week schedule for 2 months followed by a q2 months schedule for one year. They had an option to extend for a late recall feeding at 18 months, when a skin biopsy was performed 48 hours after sand fly bites. Currently the study is fully enrolled and all human subject contact is complete. We (laboratory at NIAID) are studying the humoral, cellular immune responses using blood samples, and cytokine expression in the skin biopsy samples.
Trial information was received from ClinicalTrials.gov and was last updated in May 2015.
Information provided to ClinicalTrials.gov by Uniformed Services University of the Health Sciences.