Salvage treatment against human immunodeficiency virus

Despite dramatic declines in human immunodeficiency virus (HIV)-associated morbidity and mortality as a result of highly active antiretroviral combina tion therapies, including protease inhibitors, treatment failure occurs at such high rates as 20-50%. As drug regimens are very demanding, even short decreases of drug concentrations may trigger resistance. Viral loads can be decreased to very low concentrations, and there is no strict cut-off regar ding the definition of treatment failure. Nevertheless, continuous detectio n of HIV of more than 50 copies per mL blood plasma is a predictor of incre asing viral loads and of a suboptimal response to therapy. From a theoretic al point of view, treatment changes should be made at low HIV RNA levels, b ut fewer options often dictate a more conservative approach. Drug susceptib ility testing will be of increasing value, especially in patients experienc ing drug failure for the first time. Success of salvage therapies is closel y connected with the use of new compounds including new drug classes. As dr ugs susceptible to a multi-drug-resistant HIV are not yet available, regime ns with more than three or even with five to mine drugs are used in clinica l trials. Salvage therapies often fail in virological terms, ie in 50-80% o f patients, depending primarily on the treatment history, but immunological and clinical stability can often be achieved.