In the decades since the discovery of HIV, treatments have become increasingly more effective. Using combined antiretroviral therapy (cART) it’s generally possible to reduce the amount of HIV in the blood to undetectable levels. This does not mean that HIV has been eliminated from the body. However, it does prevent HIV from reproducing and causing the usually fatal complications that used to be unavoidable.
Combined antiretroviral therapy is also known as highly active antiretroviral therapy (HAART). It uses combinations of different types of HIV drugs to effectively treat HIV. Usually at least three different drugs are used from at least two different classes. This helps to stop HIV replication and prevent drug resistance. When the virus becomes resistant to a drug, it’s no longer an effective form of treatment. When HIV becomes resistant to one drug, it can sometimes become resistant to the entire class of drugs.
There are currently five classes of HIV drugs. These are defined by how they affect the virus.
Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
These drugs affect the action of reverse transcriptase. Reverse transcriptase is the enzyme that copies HIV’s genetic material (RNA) into a different type of genetic material. This is necessary for the virus to make copies of itself. NRTIs are also known as “nucs.”
NRTIs block the action of reverse transcriptase by serving as faulty building blocks in viral DNA production. They don’t stop the enzyme from trying to make new copies, they simply disrupt those new copies.
Examples of NRTIs include:
- abacavir (Ziagen)
- emtricitabine and tenofovir (Truvada)
- lamivudine and zidovudine (Combivir)
This class of drugs is associated with rare but sometimes severe side effects in long-term use. Some scientists think that a “nuc-sparing” treatment regimen may reduce serious side effects. This viewpoint is still controversial.
Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)
These drugs also affect reverse transcriptase. However, they act directly on the enzyme’s ability replicate. They are also known as “non-nucs.” Examples of NNRTIs include:
- efavirenz (Sustiva)
- etravirine (Intelence)
- nevirapine (Viramune)
Protease Inhibitors (PIs)
Protease is an enzyme made by HIV. It chops HIV proteins into pieces. These pieces are used to construct new copies of HIV.
Protease inhibitors work by blocking the function of protease. This helps stop the formation of new copies of functional virus. Viruses made when PIs are present are usually defective and cannot infect new cells. Examples of protease inhibitors include:
- atazanavir (Reyataz)
- darunavir (Prezista)
- fosamprenavir (Lexiva)
- ritonavir (Norvir)
Cell Entry Inhibitors
Entry inhibitors prevent HIV from getting into cells. This keeps HIV from using the cellular machinery to make copies of itself.
One specific type of entry inhibitor is a fusion inhibitor. In order for HIV to get into its target cells, it needs to bind to those cells and then fuse with the membrane of the target cell. These drugs attempt to prevent the virus from even binding to a CD4 cell. Examples of entry inhibitors include enfuvirtide (Fuzeon) and maraviroc (Selzentry).
Integrase is an enzyme that allows HIV to insert its genome into cellular DNA. Integrase inhibitors block this process. This prevents HIV from making new copies of itself. One example of an integrase inhibitors is raltegravir (Isentress).
Certain combinations of HIV drugs are available in single pill regimens. A single pill regimen combines at least three different drugs into a pill taken only once a day. These may be easier to take than other combinations of antiretroviral drugs. This is mainly because people only need to remember to take a single pill every day.
Four single pill regimens have been approved for use in the United States. They are:
- Atripla, which contains emtricitabine, tenofovir, and efavirenz
- Complera, which contains emtricitabine, tenofovir, and rilpivirine
- Stribild, which contains elvitegravir, cobicistat, tenofovir, and emtricitabine
- Triumeq, which contains dolutegravir, abacavir, and lamivudine
In addition to using antiretroviral therapy (ART) to treat HIV, it can also be used to prevent it. This is known as prophylaxis. There are two types of HIV prophylaxis.
Post-exposure prophylaxis (PeP) provides ART to people who have been exposed to HIV. For example, it may be given to a health care provider after a needle stick. It reduces the chance of an infection occurring after a known exposure.
Pre-exposure prophylaxis (PreP) provides ART to people who might be exposed to HIV. It can reduce their chance of becoming infected if an exposure occurs. However, PrEP is highly controversial.
There is also data to suggest that treating a person with HIV can help prevent them from passing on the virus. This is known as treatment as prevention (TasP). ART has been used to prevent mother-to-child transmission of HIV for many years. The use of TasP to prevent sexual transmission is a more recent innovation.
HIV and its treatments may cause side effects. They can also affect the health of various organ systems. These effects can often be treated with medication. People with HIV might need medications for:
- high blood pressure
- high cholesterol
- kidney disease
In addition, people with AIDS may need treatment for opportunistic infections. People with healthy immune systems can be exposed to a variety of viruses, fungi, bacteria, and parasites without experiencing adverse symptoms. Those with HIV or AIDS are more susceptible to infection and illness due to a weakened immune system. These infections are called “opportunistic” because they take advantage of the weakened immune system and can cause a variety of debilitating illnesses. Appropriate treatment depends on what illnesses are present.
With treatment, people with HIV can live long, full lives. That means they’re susceptible to the same conditions of aging as everyone else. Preventive healthcare is even more important for people with HIV than it is for everyone else. If you have HIV, it’s also a good idea to eat well, exercise, and avoid modifiable risk factors such as:
- excessive alcohol use
- drug use