38.5 Treatment and prevention of AIDS and vaccine development

Currently three classes of antiviral drugs are administered to the human patients.

The first class is the nucleoside analogues that inhibit reverse transcriptase activity such as 3'-azido-3'deoxythymididne (AZT), deoxycytidine analogues and deoxyadenosine analogues. These drugs may help in decreasing the levels of HIV genomic RNA in plasma for several months to years. It cannot slow down the progression of disease because the newly formed viruses with mutated version show resistance to these drugs. Non-nucleoside reverse transcriptase inhibitors and viral protease inhibitors have also been developed to combat the disease. HAART (highly active antiretroviral therapy) or ART (antiretroviral therapy) has emerged as one of the most effective triple-drug therapy as it has shown promising results by reducing the plasma viral RNA to undetectable level even up to three years.

Development of effective vaccine against HIV is on the way as it sets a priority for biomedical researchers worldwide. HIV virus has a tendency to mutate therefore construction of an effective HIV vaccine is a challenging task. Vaccines for simian immunodeficiency virus (SIV) are already out in the market and the results are encouraging. SIV is similar to HIV in terms of its infectivity to macaques that is similar to AIDS in humans. Attempts to construct a vaccine that can generate both humoral as well as antibody mediated immunity may prove a better option for HIV.