A cocktail of several antiviral drugs is usually used to control HIV infections.
Though the original HIV/AIDS pandemic that started in the 1980s killed millions, multiple drugs regimens have since made HIV (human immunodeficiency virus) a chronic illness rather than an immediately terminal one.
HIV/AIDS is an incurable disease primarily transmitted through sexual contact. HIV attacks the body by harnessing its cells to produce more copies of the virus. Once the amount of virus reaches a certain level, it overwhelms the immune system, leading to full-blown AIDS (acquired immunodeficiency syndrome). In this condition, the infected person typically dies from one of a variety of opportunistic infections or cancers that attack their nearly defenseless body.
Antiretroviral drugs, the main category of drugs used for treatment of HIV, can block the virus from reproducing itself through targeting different chemicals the virus needs to make copies or perform other functions necessary its life cycle. The drug families used to treat HIV are classified based on what part of the virus’ reproductive process they target.
Nucleoside and nucleotide analogue reverse transcriptase inhibitors (NRTIs), for example, block reverse transcriptase. This is an enzyme the virus needs to infect white blood cells. Less reverse transcriptase means fewer newly infected cells. Protease inhibitors, on the other hand, block protease. Protease is crucial for HIV to make copies of itself, so less protease means the virus’ ability to colonize more cells is diminished. These and other drugs are prescribed in combination to attack the virus from various angles, which ideally leads to a more effective treatment with less drug resistance than single-drug treatment.
The ultimate goal of treatment is getting the viral load (the number of copies of the HIV in a person’s body) down below detectable levels. Periodic blood testing is an important part of therapy; as long as those viral load and antibody levels are below a proscribed range, people with HIV can stave off AIDS and other serious symptoms. This therapy also offers some protection to the infected person’s sex partner or partners.
People with HIV should note, however, that even when their infections are undetectable through lab tests, the viral load will rebound if they quit therapy or start missing doses. Some infections may also develop resistance to a particular drug cocktail, forcing treatment teams to come up with new regimens to beat back the resurgence of virus in the body.
The following are the different drug types currently used in treatment regimens for HIV:
Antiviral treatment options have primarily included combinations of two NRTIs, often referred to as “nucs,” and a third drug, typically being a boosted protease inhibitor, a NNRTI, often called “non-nucs,” and integrase strand transfer inhibitors such as RAL, EVG, DTG, or BIC. Many of these drugs are available in fixed-dose combinations as well as increasing numbers of drugs as single-tablet regimens.
This article will describe each family of drugs currently available for standard treatment and control of HIV infections.