A Phase I Safety and Immunogenicity Trial of an Alphavirus Replicon HIV Subtype C Gag Vaccine (AVX101, Alphavax, Inc.) in Healthy HIV-1 Uninfected Adult Volunteers
Overview
- Phase
- Phase 1
- Intervention
- Not specified
- Conditions
- HIV Infections
- Sponsor
- AlphaVax, Inc.
- Enrollment
- 48
- Locations
- 7
- Primary Endpoint
- Grade IV adverse events
- Status
- Completed
- Last Updated
- 13 years ago
Overview
Brief Summary
The purpose of this study is to see if different doses of an experimental HIV vaccine are safe and to study how the immune system responds to the vaccine. The vaccine will be tested in healthy, HIV uninfected volunteers. AVX101 contains only one of the many substances that HIV needs to make more copies of itself; therefore, the vaccine cannot cause HIV or AIDS.
Detailed Description
This study was designed to evaluate the safety and immunogenicity of an alphavirus replicon HIV subtype C gag vaccine. This vaccine utilizes a propagation-defective replicon vector system derived from an attenuated strain of Venezuelan Equine Encephalitis (VEE) virus. The vaccine replicon expresses the gag gene from a South African subtype C isolate of HIV-1. This study evaluated the AVX101 vaccine in healthy, HIV uninfected volunteers in both the United States and South Africa. Participants will be randomized to receive either vaccine or placebo at study entry and again at Months 1 and 3. The study was originally designed to enroll four groups of participants in both the US and South Africa, with successive groups receiving increasing doses of the vaccine, but was later amended to enroll only two groups. Twelve US participants (US Group 1) were randomized to receive either vaccine or placebo. After a review of initial safety data from this group, 12 South African participants (SA Group 1) were randomized to receive the same vaccine dose as US Group 1 or placebo, while 12 US participants (US Group 2) were randomized to receive the next higher vaccine dose or placebo. Review of safety data from SA Group 1 and US Group 2 was used to inform the decision to begin enrollment into SA Group 2 . Participants had nine study visits over 12 months. Study visits included clinical evaluation, urine and blood tests, and HIV tests. After each injection, participants were asked to record their temperature and any symptoms each day for 7 days and report them to the clinic staff.
Investigators
Eligibility Criteria
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Outcomes
Primary Outcomes
Grade IV adverse events
Time Frame: 1 year
The sample size at each vaccine dose level was selected such that the stopping rule for not escalating the dose (2 or more vaccine-related Grade IV adverse experiences) would be met with high probability if the true toxicity rate was above 15-20%, and such that dose escalation would occur with high probability if the true toxicity rate was less than 5%.
Secondary Outcomes
- Local and systemic adverse events(7 days after each dose)
- Binding antibodies by ELISA(1 year)
- Chromium release CTL assay(3 months)
- IFN-gamma ELISpot assay(3 months)
- Antibodies to VEE virus(1 year)
- Replication-competent viral vector viremia(2 weeks after each vaccine dose)
- Lymphoproliferation assay(1 year)