Chapter 14 : Antiviral Therapies

Abstract:

A brief historic account of anti-HIV therapies is provided in this chapter, followed by an update on present treatment approaches. The current antiviral drugs, when used in combination, now considered a cocktail of highly active antiretroviral therapy (HAART), have shown promise in controlling HIV infection. Nevertheless, the need for adherence to treatment and the toxic effects of certain drugs are noteworthy and encourage further studies to improve anti-HIV strategies. Some infected individuals and some clinicians are reluctant to begin early therapy for HIV infection because they fear that resistance will emerge and no further antiviral drugs will be available. Soon after the introduction of HAART, several studies indicated that despite the absence of detectable circulating HIV, reservoirs of infected CD4+ cells could remain in the infected individual for 4 to 60 years. Importantly, drug resistance appears to be less prevalent in areas in which adherence to therapy is emphasized. While current antiviral drugs have had substantial beneficial effects on HIV infection and development of disease, the side effects can be very harmful to the infected individual. Immune-based therapies may help with HAART to restore immune cell numbers and some function, the full restoration of the immune system should be an important objective. As HAART can reduce both humoral and cellular immune responses to HIV, approaches have been initiated to maintain or enhance anti-HIV responses during therapy. Information on many different drugs showing anti-HIV activity in vitro appears regularly in the literature, but their clinical efficacy awaits further evaluation.