The field of HIV therapeutics has evolved dramatically since 1989, when zidovudine was introduced as the first antiretroviral agent. Since then, nearly 30 drugs have been approved for treating HIV infection. Despite the success of combination triple treatment, known as highly active antiretroviral therapy (HAART), in reverting immunosuppression in infected individuals and limiting viral transmission, nearly 35 million people are currently living with HIV worldwide. In contrast to hepatitisC,whose etiological agent can be eradicated with proper antiviral therapy, the current treatment goal in HIV infection is the achievement and maintenance of undetectable viremia in subjects otherwise infected for a lifetime.
Not all drug combinations are equally effective in the various distinct group populations. In this issue of Hot Topics in HIV and Other Retroviruses, well recognized experts in the field of antiretroviral therapy have been invited to address how best to manage antiretroviral drugs in three different scenarios. Firstly, drug-naïve individuals are addressed. In these individuals, the antiviral potency must be balanced with the risk of causing side effects (in both short and medium-long term), and the quality of life must not be compromized with complicated posologies. Secondly, antiretroviral-experienced patients, in whom rescue interventions must be based on the principles of drug resistance are discussed. Finally, there is a substantial number of patients in special categories, that for a variety of reasons deserve special consideration about when to initiate therapy and which antiretroviral drugs are preferable. Individuals with liver disease, mainly as result of chronic viral hepatitis, are a major group for whom HAART must be personalized.
Given that the safety profile of the most recently approved antiretroviral drugs has improved in comparison with the oldest agents, the consideration of aspects of HIV infection other than immunodeficiency has attracted much attention in recent years. In this regard, the opportunity for ameliorating inflammatory phenomena surrounding HIV replication at early stages has encouraged the initiation of antiretroviral therapy in persons with elevated CD4 counts. Of course, this shift in treatment strategy is a challenge for health costs and cannot be afforded in many developing regions. However, it may produce an indirect benefit in terms of reduction in the number of new infections, given that viremia has proven to be the major determinant of transmission.