**Abstract**

Initiation of antiretroviral treatment decreased HIV related mortality and morbidity. Virological failure (a condition defined when the plasma viral load of HIV infected individuals greater than 1000 RNA copies/ml based on two consecutive viral load measurements with adherence support) have an increased risk of clinical progression to acquired immune deficiency syndrome (AIDS) and death. Nowadays, combination of highly active antiretroviral therapy is recommended to decrease the likelihood of drug resistance. However, there is emergence of drug resistance and treatment failure during treatment. Hence, managing and detecting antiretroviral treatment response is important to monitor the effectiveness of medication and possible drug switching for treatment regimens. Additionally, mechanisms of drug resistance and factors associated with immunological and virological treatment failure should be addressed.

**Keywords:** immunological response, virologic response, adverse drug reactions, HAART, drug resistance, mechanism
