How Is Human Immunodeficiency Virus (HIV) Treated?

There is no cure for human immunodeficiency virus (HIV). You can control the virus with a treatment option called antiretroviral therapy (ART), which is a combination of medications. HIV treatment is available in two forms: pills and shots.

HIV is a virus that attacks CD4 cells (white blood cells) in the immune system. The virus transmits from person to person through unprotected sex and shared needles.

Getting an HIV test is the only way to know if you have the virus. If you receive a positive test result, it's important to begin treatment as soon as possible. The virus continues to multiply and increases your risk of developing acquired immunodeficiency syndrome (AIDS) if left untreated.

The goal of treatment is to lower your viral load (the amount of HIV in your blood) to an undetectable level. This means the level of HIV in your blood is so low that you cannot measure it in a viral load test or transmit the virus to others. The immune system has a chance to recover and produce more CD4 cells when the viral load is low. This improves your ability to fight other infections and certain HIV-related cancers.

Before You Start HIV Treatment

Getting started on a treatment plan soon after receiving a positive HIV diagnosis is essential for your long-term health. Social service providers and healthcare providers alike are there to help you through the early stages of your diagnosis and help you figure out a treatment plan. 

A healthcare provider will likely consider certain factors before creating a treatment regimen that is right for you. These factors may include:

• Drug interactions between HIV medications and other medications you might be taking  
• Other issues that might make it hard to follow treatment (e.g., a lack of health insurance or the cost of medication)
• Possible side effects of HIV medications
• The ease and convenience of the treatment plan 
• Your current medical history and overall health 
• Your results from HIV drug-resistance testing

Understanding the HIV Life Cycle

HIV treatment uses antiretroviral therapy. This combination of medications slows the replication of HIV in your body at different points of the virus's life cycle. The life cycle is a process that outlines the biology behind HIV multiplication in your body. 

The life cycle breaks down into seven stages:   

1. Binding: HIV attaches itself to a CD4 cell in your immune system.
2. Fusion: HIV enters the CD4 cell.
3. Reverse transcription: HIV RNA turns into HIV DNA. RNA and DNA are genetic materials.
4. Integration: HIV DNA inserts itself into the DNA of the CD4 cell.
5. Replication: HIV builds long chains of HIV proteins, which begins the process of replicating the virus in your CD4 cells.
6. Assembly: HIV proteins and RNA move to the surface of the cell and develop into immature HIV.
7. Budding: Immature HIV moves out of the cell and matures into infectious HIV.

There are seven HIV drug classes. Each drug class targets a specific step in the HIV life cycle. The seven classes of HIV medications are:

• CCR5 antagonists
• Fusion inhibitors
• Attachment and post-attachment inhibitors 
• Nucleoside reverse transcriptase inhibitors (NRTIs)
• Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
• Integrase strand transfer inhibitors (INSTIs)
• Protease inhibitors (PIs)

It's important to note that there are no medications that block the replication or assembly steps of the HIV life cycle.

CCR5 Antagonists

HIV destroys CD4 cells, a type of white blood cell in the immune system. HIV enters CD4 cells by binding to a receptor, which is a protein that lives on the surface of a cell. Receptors send chemical signals to the cells.

HIV enters CD4 cells by binding to a CD4 receptor and an additional co-receptor: either the C-C chemokine receptor 5 (CCR5) or the C-X-C chemokine receptor 4 (CXCR4). CCR5 antagonists are a type of antiviral medication that block HIV's entry into the CD4 cell. This medication directly affects the binding phase of the HIV life cycle.

The Food and Drug Administration (FDA) has only approved one CCR5 antagonist for HIV treatment:  

Attachment and Post-Attachment Inhibitors

Attachment and post-attachment inhibitors prevent HIV from either attaching to CD4 cells or from entering them. These inhibitors prevent the virus from moving into the fusion phase of the HIV life cycle.

There are two FDA-approved medications:

Fusion Inhibitors

HIV uses a protein called glycoprotein 41 (also referred to as "gp41") to emerge inside a CD4 cell. Glycoproteins are found on the surface of HIV. Fusion inhibitors bind to gp41 and prevent the fusion phase of the HIV life cycle.

There is only one fusion inhibitor treatment available:

Fuzeon is an injection you take twice a day. Multiple injections over a long period of time can lead to skin reactions at the injection site, making it difficult to take long-term.

NRTIs and NNRTIs

Nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) are a class of HIV medications that block the conversion of HIV RNA to DNA. This prevents HIV from replicating (making copies of itself).

NRTIs and NNRTIs bind to and block an HIV enzyme called HIV reverse transcriptase. Reverse transcriptase is what HIV uses to change its genetic material from RNA to DNA. These inhibitors block the reverse transcription phase of the HIV life cycle.

There are several FDA-approved NRTIs and NNRTIs. Examples of NRTIs include:

A healthcare provider may also prescribe NNRTIs. Examples of NNRTIs include:

Integrase Strand Transfer Inhibitors 

Integrase strand transfer inhibitors (INSTIs) block an HIV enzyme known as integrase. HIV uses integrase to insert (or integrate) its viral DNA into the DNA of CD4 cells. Blocking integrase prevents HIV from making more copies of itself. Integrase strand transfer inhibitors are sometimes also referred to as integrase inhibitors. These inhibitors block the integration phase of the HIV life cycle.

Examples of INSTIs include:

Protease Inhibitors

Protease inhibitors (PIs) are a class of HIV medications that block protease, an HIV enzyme. Medicines that block protease prevent new (or immature) HIV from maturing. These medications work during the budding phase of the HIV life cycle.  

Common protease inhibitors for HIV treatment include:

Combination Medications 

A healthcare provider may recommend combination medications. These drugs combine multiple medications into one. This option helps lower the burden of having to take multiple pills or injections each day. Combination medications also can treat one or more phases of the HIV life cycle at a time. 

Some examples of combination medications include:

Living With and Managing HIV 

Receiving an HIV diagnosis can come with a lot of intense emotions and be scary. Advancements in HIV treatments have helped expand options for HIV-positive people. The most important thing you can do to manage your condition is to follow your treatment plan. 

A person's viral load can reach an undetectable level three to six months after starting treatment. There isn't a cure for HIV, but having and maintaining an undetectable viral load allows you to live a longer life. It is extremely unlikely for someone with an undetectable viral load to transmit HIV to their HIV-negative partners through sex.

Treatment is working if a person's viral load goes down after starting antiretroviral therapy. It's still crucial to stay on track with your treatment. Missing HIV treatments allows the virus to multiply quickly and weaken the immune system. 

A Quick Review

It's important to start HIV treatment as soon as possible after a positive diagnosis. The goal of treatment is to lower the amount of HIV in the blood (viral load) to an undetectable level. 

A healthcare provider will use antiretroviral therapy to treat HIV. There are several types of medications on the market that treat HIV. A healthcare provider will also work with you to find a combination of medications that works best for the stage of HIV you are in and your overall health. 

Missing or delaying treatment allows the virus to multiply quickly, weakening your immune system and making you sick. It can also allow the virus to mutate and become resistant, making it harder to treat. Talk to a healthcare provider about alternative treatment options and find a regimen that works best for your lifestyle.