MHRP researchers describe the safety and immunogenicity of a multiclade DNA vaccine prime with a muticlade recombinant adenovirus serotype 5 (rAd5) boost
RV 172: A Phase I/II Clinical Trial to Evaluate the Safety and Immunogenicity of a Multiclade HIV-1 DNA Plasmid Vaccine, VRC-HIVDNA016-00-VP, Boosted by a Multiclade HIV-1 Recombinant ADENOVIRUS-5 Vector Vaccine, VRC-HIVADV014-00-VP in HIV Uninfected Adu
- 1/28/2010
Results from the RV172 study of a vaccine candidate in East Africa conducted by MHRP were published recently in the Journal of Infectious Diseases 2010 Jan 11. The data show the DNA/rAd5 vaccination regimen was safe and induced HIV type 1 multi-clade T cell responses, which were not significantly affected by titers of preexisting rAd5 neutralizing antibody.
“The study achieved its primary goal of demonstrating safety and immunogenicity of the product for further efficacy testing,” noted Dr. Merlin Robb, MHRP’s Deputy Director for Clinical Research and Study Chair. The vaccine, which was developed by the Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), is a 6-plasmid mixture encoding HIV envelope subtypes A, B, and C and subtype B gag, pol, and nef, and an rAd5 expressing identical genes, with the exception of nef.
HIV-specific T cell responses were detected in 63% of vaccinees. Titers of preexisting Ad5 neutralizing antibody did not affect the frequency and magnitude of T cell responses in prime-boost recipients but did affect the response rates in participants that received rAd5 alone.
RV 172 was conducted by the MHRP network as a multicentre study involving 324 healthy HIV-1 uninfected adult volunteers (186 receiving vaccine and 138 receiving placebo) enrolled at MHRP’ three East Africa sites:
- Makerere University Walter Reed Project in Kampala, Uganda
- Mbeya Medical Research Program in Mbeya, Tanzania
- Walter Reed Project in Kericho, Kenya
RV 172 was also conducted by two other networks as identical studies within their respective networks: HVTN 204 and IAVI 001. These studies were sponsored by the Vaccine Research Center (VRC), NIAID, NIH.