Human immunodeficiency virus (HIV) infection shows that knowledge of the molecular mechanisms involved in the pathogenesis can lead to the rapid development of new drugs to treat infected patients. Since the description of acquired immunodeficiency syndrome (AIDS) in 1981 and the identification of its causal agent in 1983, twenty-three antiretrovirals, belonging to 5 families, have been marketed. The viral entry point is one of the preferred therapeutic treatment targets, but the development of antagonists against the different HIV receptors has been a long process and fraught with difficulties. Maraviroc is the first CCR5 antagonist drug approved for clinical use and represents a milestone in the development of new treatments against HIV infection. Maraviroc is a novel drug and different from the rest of the antiretrovirals due to the special characteristics of its mechanism of action and is also the first antiretroviral directed towards a cell target. The different aspects of treatment with Maraviroc are analysed in this article; mechanism of action, toxicity, efficacy, resistance mechanisms, and its role in the context of antiretroviral treatment of the HIV infected patient.