Shortly following the discovery of HIV in 1981, a variety of therapies using one drug were introduced to people living with HIV or AIDS. This included the drug AZT. Despite initial success, these “monotherapies” proved to be ineffective in slowing the virus’s progression.
This failure was due to HIV’s ability to quickly develop resistance to these single-drug treatments. In other words, HIV mutated (changed) into a form that no longer responded to the individual drugs.
In 1995, a combination drug treatment known as the “AIDS cocktail” was introduced. This type of therapy is now known as highly active antiretroviral therapy (HAART). It’s also called combination antiretroviral therapy (cART) or simply antiretroviral therapy (ART).
Regardless of its name, HAART has led to dramatic improvements in people who have used it. People have experienced decreased viral loads (the amount of HIV in their body) and increased counts of CD4 cells (immune cells that are destroyed by HIV).
According to the Centers for Disease Control and Prevention, people who take antiretroviral therapy as prescribed and maintain an undetectable viral load have “effectively no risk” of transmitting HIV to others.
In addition, their life expectancies have become much closer to typical life expectancies. One of the main reasons for HAART’s success is that it helps prevent resistance to any single drug used.
Read on to learn more about the life-changing treatment called HAART.
antiretroviral therapy drug regimen classes
A variety of HAART drug therapies are currently available by prescription. Each drug included in the combination therapy serves a unique purpose, but together they work to accomplish several important goals:
- Prevent the virus from replicating and reduce viral load.
- Help restore CD4 counts and immune function.
- Reduce complications from HIV and improve survival.
- Reduce transmission of HIV to others.
The current classes of drugs included in antiretroviral therapies include:
- Nucleoside reverse transcriptase inhibitors (NRTIs). HIV requires an enzyme called reverse transcriptase (RT) in order to replicate. By offering faulty versions of RT to the viruses, NRTIs block the virus’s ability to replicate.
- Non-nucleoside reverse transcription inhibitors (NNRTIs). These inhibitors disable a key protein that HIV requires to replicate.
- Protease inhibitors (PIs). This inhibitor disables the protein called protease, another key building block required by HIV to replicate.
- Entry or fusion inhibitors. These inhibitors block the virus’s ability to enter the body’s CD4 cells.
- Integrase inhibitors (INSTIs). Once HIV has penetrated a CD4 cell, it inserts genetic material into the cells with the assistance of a protein called integrase. These inhibitors block the virus’s ability to complete this crucial replication step.
HIV treatment protocols
According to the National Institutes of Health, the current recommendations for an initial HIV drug regimen include three HIV medications from two or more different drug classes. Typically, this includes:
- two NRTIs with an INSTI, NNRTI, or PI
- ritonavir or cobicistat as a booster
Once a regimen is put into place, the person’s healthcare provider will carefully monitor their ongoing reaction and success levels. If the person has severe side effects or if the regimen doesn’t work, the healthcare provider can make changes to the drug regimen.
Antiretroviral treatment is currently recommended for all people living with HIV. However, certain situations make receiving treatment more urgent. Examples of these situations involve people who:
- are currently pregnant
- have previously experienced HIV-related dementia, cancer, or other HIV-related complications such as infections or nerve pain
- have hepatitis B or hepatitis C
- have had CD4 counts below 200 cells/mm3
Once an antiretroviral treatment is started, it should be continued long term. This helps maintain a low viral load and a normal CD4 count.
The introduction of HAART changed everything about HIV treatment and prevention. It’s brought a sense of renewed hope for increased longevity in people living with HIV. In addition, it’s provided significant improvements in the overall quality of life for people living with HIV.