/ 8 February 2007

Aids initiative announces HIV-vaccine trial

The South African Aids Vaccine Initiative (Saavi), which is supported by power parastatal Eskom and the South African government, announced on Thursday the start of the first large-scale test of a concept HIV vaccine — which will involve 3 000 participants in South Africa.

The Phambili — ”going forward” — trial, which will be conducted with the international HIV-Vaccine Trials Network (HVTN), is the largest HIV-vaccine trial in South Africa to date. Saavi is an initiative of the South African government, and a programme of the Medical Research Council (MRC).

In a statement released by MRC president professor Anthony Mbweu, it said the participants would be recruited from four provinces — Gauteng, North West, Western Cape and KwaZulu-Natal.

The vaccine trial sites were located in Soweto, Cape Town, Klerksdorp, Medunsa and Durban.

Mbewu said the test vaccine was one of the ”most promising” currently available. The trial is known as ”test of concept” because it enabled researchers to test that the vaccine either prevented HIV infection or lowered HIV levels in those infected.

”South Africa is an excellent choice for this trial. Whilst there are numerous countries with similar high levels of infection, South Africa is unique in its good clinical infrastructure, a well-established national HIV-vaccine initiative, and experience in running clinical trials,” said University of the Witwatersrand’s national principal investigator of the Perinatal HIV-Research Unit Professor Glenda Gray.

”South Africa is also one of a few African countries that have internationally recognised immunology laboratories capable of evaluating the immunogenicity of the vaccine within the country,” she said.

Immunogenicity is the ability of a particular substance to provoke an immune response.

The South African study was likely to provide important new data on how the test vaccine might work in a predominantly heterosexual HIV epidemic, how well the vaccine works in women, and whether the vaccine works in populations with pre-existing immunity to the viral vector used in the vaccine.

Volunteers will be healthy HIV-negative males and females, aged 18 to 35 years, who are sexually active and not pregnant.

The test vaccine to be used in this study was developed and manufactured by Merck and has already been extensively tested in the Americas, Africa and, Australia. Thousands of people have been involved in the initial testing phases, the statement said.

The Phambili trial is to be conducted by the HIV-Vaccine Trials Network

(HVTN), which is funded through a cooperative agreement with the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health in the United States. ‒ I-Net Bridge