Clinical Trial: A Zika Virus DNA Vaccine in Healthy Adults and Adolescents

Study Status: Enrolling by invitation
Recruit Status: Enrolling by invitation
Study Type: Interventional

Official Title: A Phase 2/2B, Randomized Trial to Evaluate the Safety, Immunogenicity and Efficacy of a Zika Virus DNA Vaccine in Healthy Adults and Adolescents

Brief Summary: This is a multicenter, randomized, study to evaluate the safety, immunogenicity, and efficacy of VRC-ZKADNA090-00-VP (Zika virus wildtype DNA vaccine) or placebo. In Part A, the primary objective is to evaluate the safety and tolerability of the vaccine. In Part B, the primary objectives are to evaluate the safety and efficacy of the vaccine compared to placebo.

Detailed Summary:

This is a multicenter,randomized study to evaluate safety, immunogenicity, and efficacy of a 3-dose vaccination regimen with the Zika virus wildtype (ZIKVwt) DNA vaccine, VRC-ZKADNA090-00-VP or placebo (VRC-PBSPLA043-00-VP). The placebo is a sterile phosphate-buffered saline (PBS). The hypotheses are that the ZIKVwt DNA vaccine will be safe and will elicit a ZIKV-specific immune response.

Participants will receive study product intramuscularly (IM) in the limbs as specified by the group assignment by PharmaJet needle-free device. In Part A, 90 participants will be randomized to vaccine at a 1:1:1 ratio to receive a 4 mg or 8 mg dose of vaccine split between 2 or 4 injections. In Part B, 2400 participants will be randomized to vaccine or placebo in a 1:1 ratio.

Vaccine safety and tolerability will be assessed by monitoring of clinical and laboratory parameters throughout the study. Solicited reactogenicity symptoms will be collected for 7 days after each product administration. The study schedule will include clinic visits with safety and immunogenicity blood samples collected at particular time points.

The vaccine dose and administration plan for Part B will be selected based on Part A and Phase 1 data. Vaccine efficacy will be evaluated in Part B by comparing incidence of symptomatic ZIKV infections between vaccine and placebo groups. During the study, when participants exhibit any possible symptom of ZIKV infection, they will be evaluated by blood and urine ZIKV polymerase chain reaction (PCR). Stored blood and urine samples will also be assessed retrospectively by ZIKV PCR to identify possible asymptomatic cases. A Data and Safety Monitoring Board (DSMB) will oversee the study.

Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

Current Primary Outcome:

• Local Reactogenicity (Part A and B) [ Time Frame: 7 days after each product administration ]
  Occurrence of local reactogenicity signs and symptoms
• Systemic Reactogenicity (Part A and B) [ Time Frame: 7 days after each product administration ]
  Occurrence of systemic reactogenicity signs and symptoms
• Laboratory measures (Part A) [ Time Frame: Day 0 through Day 112 ]
  Occurrence of laboratory safety measures
• Laboratory measures (Part B) [ Time Frame: Day 0 through Day 308 ]
  Occurrence of laboratory safety measures
• Serious adverse events (Part A) [ Time Frame: Day 0 through Day 224 ]
  Occurrence of serious adverse events
• Serious adverse events (Part B) [ Time Frame: Day 0 through Day 672 ]
  Occurrence of serious adverse events
• New chronic medical conditions (Part A) [ Time Frame: Day 0 through Day 224 ]
  Occurrence of new-onset of chronic medical conditions
• New chronic medical conditions (Part B) [ Time Frame: Day 0 through Day 672 ]
  Occurrence of new-onset of chronic medical conditions
• Confirmed cases of Dengue virus infection (Part A) [ Time Frame: Day 0 through Day 22
  
  

  Original Primary Outcome: Same as current
  
  

  Current Secondary Outcome:

  • Antibody response to VRC-ZKADNA090-00-VP (Part A and B) [ Time Frame: Day 0 to 28 days post product administration ]
    Antibody response as measured by ZIKV neutralization antibodies
  • Confirmed cases of Zika (Part B only) [ Time Frame: Day 0 through Day 672 ]
    Occurrence of confirmed cases of Zika irrespective of symptoms
  
  
  

  Original Secondary Outcome: Same as current
  
  Information By: National Institute of Allergy and Infectious Diseases (NIAID)
  

  Dates:
  Date Received: March 28, 2017
  Date Started: March 29, 2017
  Date Completion: January 2020
  Last Updated: April 6, 2017
  Last Verified: April 2017