The National Institute of Allergy and Infectious Diseases (NIAID) is set to initiate a new research study, HVTN 702, of a new HIV vaccine in South Africa.
The vaccine regimen will test two experimental vaccines, a canarypox vector-based vaccine known as ALVAC-HIV and a two-component gp120 protein sub-unit vaccine with an adjuvant to improve the body’s immune response to the vaccine.
The vaccines are free from HIV and are therefore safe to be administered to the study subjects.
ALVAC-HIV, supplied by Sanofi Pasteur and the protein vaccine, supplied by GSK, are modified versions of RV144 to be specific to HIV subtype C, the predominant HIV subtype in southern Africa.
The protein sub-unit vaccine is also combined with GSK-supplied MF59, which is a different adjuvant than the one used in RV144 in order to result in improved robust immune response.
The vaccine regimen of the study also includes booster shots, which will be administered after one year to prolong the early protective effect observed in RV144.
The HVTN 702 study is a large, advanced-stage clinical trial intended to determine the safety, tolerability and efficacy of the investigational HIV vaccine regimen to prevent HIV infection among 5,400 healthy, sexually active South African men and women aged 18 to 35.
HVTN 702 Protocol Chair Glenda Gray said: “The people of South Africa are making history by conducting and participating in the first HIV vaccine efficacy study to build on the results of the Thai trial.
“HIV has taken a devastating toll on South Africa, but now we begin a scientific exploration that could hold great promise for our country.
“If an HIV vaccine were found to work in South Africa, it could dramatically alter the course of the pandemic.”
The experimental vaccine regimen is based on the RV144 clinical trial previously held in Thailand by the US Military HIV Research Program and the Thai Ministry of Health.
Image: Electron micrograph displaying HIV-1 (green) in cultured lymphocyte. Photo: courtesy of C. Goldsmith.