Current antiretroviral drugs for human immunodeficiency virus infection: review article

Currently, there are about 37 million people worldwide living with human immunodeficiency virus (HIV) /AIDS, with an estimated two million new cases per year globally. According to estimates from the World Health Organization (WHO), only 75% of the population with HIV know their status. Initially, HIV infection was associated with significantly increased rates of mortality and morbidity. However, the rapid advances in treatment and the advent of different classes of antiretroviral drugs over time have led to change the face of HIV/AIDS from a deadly infection to chronic and manageable disease. There is strong evidence that HIV-infected patients undergoing antiretroviral therapy have longer lives and are less likely to transmit infection to their sexual partners. Since the introduction of zidovudine in 1987 as the first antiretroviral drug, significant strides have been made in antiretroviral therapy. The introduction of potent antiretroviral drugs for the treatment of HIV infection has been one of the significant events in the evolution of modern medicine. Antiretroviral therapy refers to the use of drugs in the treatment of HIV. Generally, these drugs are categorized based on the steps of the HIV life cycle suppressed by them. There are six main classes of antiretroviral agents including nucleoside/ nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, fusion inhibitors, co-receptor inhibitors, and integrase inhibitors. Combination antiretroviral therapy should be considered for HIV patients to achieve the highest viral suppression rate, and to reduce the risk of resistance development and morbidity and mortality associated with AIDS. Achieving and maintaining HIV viral load suppression among treated patients has remarkably increased over the last years due to the development of potent and well-tolerated agents which can be co-formulated as a once-daily single-tablet or fixed-dose combination for simplification. However, there are some limitations preventing patients to benefit from this treatment. The main goals of HIV therapy in the future are to overcome the limitations of current treatment, including side effects. This review will provide an overview of advances in the current antiretroviral drugs by focusing on their pharmacokinetics, mechanism of action, dosing recommendations, and adverse events for each drug class.