Safety and immune response evaluation of a Rift Valley Fever vaccine

A Phase 2 Open Label Safety and Immunogenicity Study of Rift Valley Fever Vaccine, Inactivated, Dried, TSI-GSD 200, Lot 7, Run 2, in Adult Subjects at Risk of Exposure to Rift Valley Fever Virus

PHASE2 · U.S. Army Medical Research and Development Command · NCT03609398

This study is testing a new vaccine for Rift Valley Fever to see if it is safe and helps people at risk build immunity against the virus.

Quick facts

PhasePHASE2
Study typeInterventional
Enrollment500 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorU.S. Army Medical Research and Development Command (fed)
Drugs / interventionsmethotrexate, prednisone
Locations1 site (Fort Deterick, Maryland)
Trial IDNCT03609398 on ClinicalTrials.gov

What this trial studies

This study evaluates the safety and immune response of the Rift Valley Fever vaccine, TSI-GSD 200, Lot 7, Run 2. Participants, aged 18 to 65, who are at risk of exposure to the Rift Valley Fever virus, will receive the vaccine in a 1.0-mL dose administered subcutaneously. The study aims to gather data on the vaccine's immunogenicity by measuring the plaque reduction neutralization titers before and after vaccination. Enrollment is limited to individuals who have low baseline immunity to the virus and meet specific health criteria.

Who should consider this trial

Good fit: Ideal candidates are individuals aged 18 to 65 who are at risk of exposure to the Rift Valley Fever virus.

Not a fit: Patients with pre-existing high immunity to Rift Valley Fever or those outside the specified age range may not benefit from this study.

Why it matters

Potential benefit: If successful, this vaccine could provide effective protection against Rift Valley Fever for at-risk populations.

How similar studies have performed: Other studies on vaccines for similar viral infections have shown promising results, indicating potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Be 18 to 65 years old at time of consent.
* Have RVF plaque reduction neutralization 80% titers (PRNT80) \<1:10 for primary series.
* Have RVF PRNT80 (plaque reduction neutralization 80% titer) \<1:40 for booster series.
* If female of childbearing potential, must agree to have a urine pregnancy test on the same day before each vaccine administration. (Exception: documented hysterectomy or ≥3 years of menopause.) The results must be negative. Females must agree not to become pregnant for 3 months after receipt of the last study treatment (vaccination).
* Be considered at risk for exposure to RVF virus and who have submitted a Request for IND Vaccines for the RVF vaccine.
* Sign and date the approved informed consent document and HIPAA Authorization.
* Have in their charts:
* medical history (including concomitant medications) within 60 days of planned first administration of vaccine
* physical examination and laboratory tests within 1 year
* previous chest radiograph results and electrocardiogram
* Be medically cleared for participation by an investigator. (Examinations and/or tests may be repeated at the discretion of the PI.)
* Be willing to return for all follow-up visits.
* Agree to report any adverse events (AEs) that may or may not be associated with administration of the vaccine for at least 28 days after administration and agree to report all serious adverse events (for example, resulting in hospitalization) for the duration of the subject's participation in the study.
* Agree to defer blood donation for 1 year after receipt of the vaccine

Exclusion Criteria:

* Have completed previous RVF vaccine study as a nonresponder (PRNT80 \<1:40).
* Have clinically significant abnormal laboratory results (including evidence of hepatitis C, hepatitis B carrier state) or elevated liver function tests (two times the normal range or at the discretion of the PI).
* Have a personal history of an immunodeficiency or received treatment with an immunosuppressive medication, such as systemically administered glucocorticoids (eg prednisone) within 1 month before planned administration of the vaccine or with other immunosuppressive therapies within 6 months of planned administration of the vaccine. Other immunosuppressive therapies include all cancer chemotherapeutic agents, drugs to prevent transplant rejection, interferons, monoclonal antibodies, protein kinase inhibitors, methotrexate, TNF (tumor necrosis factor) inhibitors, and any other drug determined to be immunosuppressive by the PI. Current administration of topical, inhalational, or intranasal glucocorticoids is not excluded.
* Have confirmed HIV infection.
* Have positive pregnancy test or be breastfeeding female.
* Have any known allergies to components of the vaccine:
* Fetal rhesus monkey lung cells
* Formaldehyde
* Neomycin sulfate
* Streptomycin
* Sodium bisulfite
* Human serum albumin (HAS)
* RVF virus (Entebbe strain)
* Have administration of another vaccine or investigational product within 28 days of RVF vaccination.
* Have any unresolved AE resulting from a previous immunization.
* Have a medical condition that, in the judgment of the PI, would impact subject safety.

Where this trial is running

Fort Deterick, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Rift Valley Fever

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.