/ 19 June 2003

First HIV vaccine trials to begin in SA

The Medicines Control Council (MCC) has approved the first human clinical trials for a phase one HIV vaccine trial in South Africa, with the use of cutting edge technology, the government news agency BuaNews reported on Thursday.

This is the first HIV vaccine trial to be approved in the country and the first in the world to test a subtype C vaccine.

The SA Aids Vaccine Initiative (SAAVI) said this was a phase one human clinical trial of the ArV vaccine to assess the safety and immune system responses induced by this new vaccine technology.

“‘It [the technology] utilises virus-like particles, containing parts of an attenuated strain of Venezuelan equine encephalitis (VEE) virus and a gene from a South African strain of the HIV virus, to deliver the vaccine to the immune system,'” said the SAAVI.

This gene is a ‘promising’ target for the cellular immune responses thought to be a prerequisite for a successful HIV vaccine.

SAAVI said the trial would involve a small number of volunteers in both South Africa and the US — a total of 96 participants from both countries respectively.

“Volunteers will be involved in the trial for about a year and it is anticipated that with data analysis the trial will last approximately two years.”

The HIV Vaccine Trials Network (HVTN) is conducting the trial, which will take place at the Perinatal HIV Research Unit at the Chris Hani Baragwanath Hospital in Soweto, and the SAAVI Vaccine Research Unit at the Medical Research Council (MRC) in Durban. The US trial sites will be at the universities of Johns Hopkins, Columbia, Rochester and Vanderbilt.

Twenty-four volunteers are required at each South African site and SAAVI said recruitment was continuing in preparation for the first vaccinations.

“Volunteers will be healthy, HIV-negative adults who are willing and able to give informed consent and intensive pre-recruitment educational. Community awareness activities have been conducted at both sites in South Africa.

“The study that has been approved will begin by enrolling 12 volunteers in the US, and additional volunteers will be enrolled in the US and SA once initial safety data from these 12 volunteers has been reviewed.”

For safety reasons, potential volunteers would be supplied with detailed information about the candidate vaccine, including ‘intensive’ risk reduction counselling and clinical monitoring on an ongoing basis done to avoid exposure to unnecessary risk.

Athmanundh Dilraj, a coordinator at the Durban site, expressed confidence in the trial, saying over 70 candidate vaccines were tested and this specific one had not shown many side-effects.

As scientists have cautioned in the past that it could take years before a vaccine is registered against HIV, Dilraj said this first trial could take over 18 months to complete, phase two could take three years while the third could take three years.

“Generally, it could take between seven and ten years before an appropriate vaccine is registered,” he said.

SAAVI also explained that a phase one trial is a safety trial, aiming to confirm the test did not produce significant side effects in human volunteers. For this reason, volunteers would be closely monitored over a 12-month period, using this vaccine, which ‘has already been extensively tested in laboratory and animal studies’. Its protocol had also been reviewed and approved by the US Food and Drug Administration (FDA) as well as by multiple ethics committees in South Africa.

As the vaccine contains only a copy of a small section of genetic material from HIV, and does not include the genetic elements needed to reconstitute live HIV, SAAVI said there was no possibility of the vaccine itself causing HIV infection.

“The vaccine is also designed in such a way that its VEE components cannot generate VEE virus or cause VEE infection.”

It said the award winning ArV vaccine technology, was originally developed by researchers at the University of Carolina (UNC) and the US Army Medical Research Institute of Infectious Diseases.

It has been applied to HIV by an international collaboration of researchers at the UNC, the University of Cape Town, the MRC, and AlphaVax, a North Carolina biotechnology company. – I-Net Bridge