HIV Vaccine Info-line


Questions and answers

What is a vaccine?
A vaccine is a substance that is introduced to the body to teach it to recognise and defend itself against bacteria and viruses that cause disease. A vaccine causes a response from the immune system (the body’s defence system) preparing it to fight if exposed to the virus or bacteria at a later time. A successful vaccine can cause the body to stop or disable an invading virus or bacteria. A vaccine is not a cure, but ideally prevents infection or slows disease progression.
Where do vaccines come from?
The first modern vaccine was developed in 1796 by Edward Jenner to prevent smallpox. Through vaccination, smallpox, which at the time killed about a million people per year in Europe, has been eradicated. Now, there are also vaccines for many other diseases like rabies, tetanus, measles, mumps and polio that annually save millions of lives and prevent disease.
Why an HIV vaccine?

According to the December 2007 report by the United Nations Programme on HIV/AIDS (UNAIDS), about 33.2 million people are living with HIV worldwide. There are an estimated 5.41 million South Africans who are infected.

According to the Medical Research Council’s (MRC) 2001 report The Impact of HIV/AIDS on adult mortality, AIDS accounted for about 25% of all deaths in 2000 and was the biggest cause of death in South Africa.

Development of a vaccine is one of the best hopes to control the HIV epidemic and must be part of a bigger strategy including HIV prevention, education, treatment, care and support.

How does an HIV vaccine work?
A successful preventative HIV vaccine will teach the body to recognise HIV so preparing the person’s immune system to fight back if exposed to HIV, by e.g. unsafe sex, at a later date. A successful therapeutic HIV vaccine will boost the immune response to HIV of people already infected with the virus (so their bodies can better fight HIV).
Can an HIV vaccine cause HIV infection?
An HIV vaccine cannot cause HIV infection or AIDS. HIV vaccines do not contain any whole or live HIV. They generally contain only harmless parts or copies of parts of the HI virus which cannot cause HIV infection. An HIV vaccine is a bit like a motor car with its engine removed. It is still recognisable as a car but it can’t drive.
Is there an HIV vaccine available?
Currently, there is no effective HIV vaccine available. However, there are several possible vaccines that may work and are being tested in clinical trials. Testing a vaccine takes a long time to ensure that it is safe and effective. It has usually taken 10 to 20 years to bring most commonly used vaccines into general public use.
How do you test an HIV vaccine?
Each potential HIV vaccine is tested in various stages taking a number of years. These stages include initial laboratory work, followed by testing the vaccine in animal, and then human clinical trials. There are three phases of human clinical trials. Phase I includes about 50 - 120 volunteers, and tests for vaccine safety. Phase II involves about 200 - 500 volunteers. This phase tests for vaccine safety, an immune system response, and different doses and ways to give the vaccine. Phase III involves thousands of volunteers to test if the vaccine works, e.g. to prevent infection with HIV or to slow disease progression. Other trials may also occur between phases, e.g. a phase llb trial. Here researchers collect additional data to that obtained in the previous phase, phase II, to guide future research.
Who participates in the clinical trials?
Currently, people who are healthy, over 18 years in age, and are able to give informed consent can participate. They also need to be willing to have regular medical check-ups for safety monitoring. Preventative HIV vaccine trials involve HIV-negative volunteers to test if the vaccine stops infection, or slows disease progression if infection occurs. Therapeutic HIV vaccine trials involve HIV-positive volunteers to test if the vaccine strengthens their immune response to HIV.
How are people’s rights safeguarded?

People’s rights are safeguarded by:

  • our Constitution, laws and regulations;
  • review and monitoring by independent bodies or institutions. These include: research ethics committees, the Medicines Control Council; an Independent Data and Safety Monitoring Board for larger trials and so on;
  • well informed community members who actively participate in the research and development process;
  • ensuring ‘informed consent’. This is the agreement, free of coercion or undue influence, by volunteers to participate, based on an understanding of the relevant information;
  • taking active steps to minimise potential harm to participants and to maximise the expected benefits of research;
  • ensuring that trial participants and research communities are chosen fairly;
  • employing skilled research staff; and
  • taking steps to maximise confidentiality.
What about HIV vaccines in South Africa?
There are a number of potential vaccines in development in South Africa. Co-ordination of the development and testing of these vaccines is the responsibility of the South African AIDS Vaccine Initiative (SAAVI). All vaccine trials must be approved by the Medicines Control Council (MCC) and relevant health research ethics committees (RECs). We will only know if these potential vaccines work for people living in South Africa by testing them in our communities.
Where are the trials being held?
Currently, there are trial sites in Gauteng, the North-West, KwaZulu-Natal and the Western Cape. Trial sites are also in development in the Limpopo and Eastern Cape provinces.
Why is it necessary to do many trials?
As yet it isn’t known which HIV vaccine design will give a strong enough immune response to protect against the virus - so many different designs need to be tested. The testing process takes a long time (at least 7 to 10 years for each vaccine) so it makes sense to run several trials on various designs at the same time to develop a successful vaccine faster.
What about clinical trials in other countries?
The International AIDS Vaccine Initiative (IAVI), the US National Institutes of Health (NIH), the European Union (EU), the Centers for Disease Control and Prevention (CDC) in the USA, and others, all support the development of HIV vaccines. Clinical trials are under way in many countries around the world. Several pharmaceutical companies are also involved in vaccine development. All efforts are focusing on vaccines that will be cheap to make and easy to access by both rich and poor countries.
What is SAAVI?

SAAVI is a lead programme of the South African Medical Research Council (MRC), and currently works together with partners from universities and institutions across the country. These partners include:
• immunologists and laboratory scientists;
• vaccine developers;
• ethicists;
• HIV vaccine clinical trial site teams;
• socio-behavioural scientists; and
• data specialists.

SAAVI also has several staff based at the MRC. They include senior managers, a support team and staff from Masikhulisane, SAAVI’s community involvement programme.

Apart from regular advice from its Scientific Review and Steering Committees, SAAVI also regularly collaborates with other regional and international HIV vaccine research initiatives.

Trial sites

  • PHRU, Chris Hani Baragwanath Hospital, Soweto: (011) 989-9700
  • Aurum Health Research, Klerksdorp: (018) 406-4200
  • Cape Town Clinical Trials Consortium: (021) 650-6966/ (021) 386-0053
  • University of Limpopo, MEDUNSA campus, Garankuwa: (012) 521-4251
  • CAPRISA, University of KwaZulu-Natal: (031) 260-1944

SAAVI is financially supported by

SA Medical Research Council
South African Department of Health
Italian Co operation
Istituto Superiore di Sanità
Last updated: 20-Nov-2015