HIV Vaccine

There are a lot of research going on on making HIV vaccine. The experimental HIV vaccines should produce either antibodies or cytotoxic T cells (CTLs) to fight infection. HIV vaccines currently being tested in humans are made from man-made materials that CANNOT cause HIV infection.

What's in the HIVvaccine?
In general, the vaccines are created from genetically engineered pieces of HIV proteins designed to stimulate a response in your immune system। However, each study tests a different vaccine. If you come in for a screening, the clinic will go over the details of the vaccine, including its components.

Possible Outcomes of HIV Vaccine
Scientists believe that an effective HIV vaccine, given before exposure to HIV, could have a number of possible outcomes. These include:

1. Preventing infection in most people
2. Preventing infection in some people
3. Preparing a person's immune system to block continued infection and eliminate the virus (vaccines against measles, mumps and polio work this way)
4. Delaying or preventing the onset of illness or AIDS

The long-term goal is to develop a vaccine that is 100 percent effective and protects everyone from infection. However, even if a vaccine only protects some people, it could still have a major impact on controlling the epidemic. A partially effective vaccine could decrease the number of people who get infected with HIV; those people, in turn, would not pass the virus on to others. Even when an HIV vaccine is developed, education and other prevention efforts will be needed so that people continue to practice safe behaviors.

Preventive versus Therapeutic HIV Vaccine

Preventive HIV Vaccine : Preventive HIV vaccines are designed to protect HIV-negative people and to control the spread of HIV. They are not designed to cure AIDS.
Therapeutic HIV Vaccine: Multiple HIV vaccines may be necessary to prevent infection or disease in the same way multiple drugs are needed to treat people already infected with HIV.

Researchers are also evaluating therapeutic vaccines to treat people with HIV infection or AIDS. While the same vaccine may be tested for both preventive and therapeutic effects, what works to prevent HIV infection may not necessarily work to treat people who are already infected with HIV.

Testing HIV Vaccines
Vaccine development requires several years of research in laboratories and animals before testing in humans can begin. A potential vaccine goes through three phases of testing in humans before the Food and Drug Administration (FDA) can consider licensing it for public use. The three phases of preventive HIV vaccine clinical trials are:

• HIV Vaccine Phase I - involves a small number of healthy volunteers (HIV-negative) to test the safety and various doses of the vaccine; usually lasts 12 to 18 months.
• HIV Vaccine Phase II - involves hundreds of volunteers (HIV-negative) to test the safety and immune responses of the vaccine; can last 2 to 4 years. The Step Study is Phase II trial.
• HIV Vaccine Phase III - involves thousands of volunteers (HIV-negative) to test the safety and effectiveness of the vaccine; can last 3 to 4 years.

Throughout all phases of human testing, independent reviewers regularly monitor the study to ensure the safety of the volunteers.