| Chapter 1: | Introduction |
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anti-HIV drugs. As the public remains optimistic about a cure for HIV/AIDS, pharmaceutical companies continue to venture new medication innovations that may completely destroy the virus.
Anti-HIV Treatment Drugs
Currently, more than 25 different types of HIV antiretroviral drugs have been innovated and approved by the U.S. FDA (AIDSinfo, 2008; Hanson & Hicks, 2006; Laing & Hodgkin, 2006; Palella et al., 1998; Yeni et al., 2005). These drugs are grouped into six classes, namely nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), fusion inhibitors, integrase inhibitors, and entry inhibitors (AIDS InfoNet, 2011; Department of Health and Human Services [DHHS], 2007; McNicholl, 2007). Anti-HIV drugs’ regimen dosages usually constitute three drugs from at least two different classes, and they target specific stages of the HIV lifecycle, which begins and is completed within the CD4 cell. Each drug blocks continuation of the replication process at a designated stage in the HIV lifecycle (de Béthune, 2009). For example, drugs that belong to the entry inhibitor class are utilized to prevent HIV from entering or attaching itself to the CD4 cell, which is the first stage of replication. The second stage is targeted by the NRTIs and NNRTIs, which prevent HIV from making its new DNA from its RNA by blocking the enzyme known as reverse transcriptase (de Béthune, 2009). Integrase inhibitors prevent HIV from integrating its newly formed DNA into the CD4 cell during the third stage. The fourth stage is targeted by PIs that hinder the protease enzyme from enabling completion of the HIV reproduction process. The three combination drugs commonly used to treat HIV include one NRTI, one NNRTI, and one PI (Tarby, 2004). Each dose combination is sometimes referred to as a cocktail (GlaxoSmithKline, 2008; Hammer et al., 2006). These combination drugs have somewhat reversed what may have been initially perceived by many global cultures as the curse of AIDS.