HAART (Highly Active Antiretroviral Therapy) Definition

SAN ANSELMO, CA - NOVEMBER 23: Bottles of antiretroviral drug Truvada are displayed at Jack's Pharmacy on November 23, 2010 in San Anselmo, California. A study published by the New England Journal of Medicine showed that men who took the daily antiretroviral pill Truvada significantly reduced their risk of contracting HIV. (Photo Illustration by Justin Sullivan/Getty Images). Justin Sullivan/Getty Images News/Getty Images

What is HAART?

HAART, or highly active antiretroviral therapy, refers to the use of combinations of various antiretroviral drugs with different mechanisms of action to treat HIV. It is an old-school term for HIV treatment.

There are several different drug "cocktails" used as HAART, but it is the use of a combination of drugs that is the most important hallmark of HAART as therapy.More recently, people tend to refer to this type of multi-drug therapy as cART.

That stands for combination antiretroviral therapy.  

It is very important to treat HIV with a multi-drug regimen. HIV can easily develop resistance to individual antiretroviral therapies. It is much harder for HIV to become drug-resistant when multiple antiretroviral drugs with varied mechanisms of action are combined into a single HIV treatment.That is because it would require multiple, simultaneous mutations for resistance to develop and survive. That's far less likely than a single mutation developing for single drug resistance. With different drugs, there are different pressures to evolve. 

HAART usually involves a combination of at least three drugs from two or more classes of antiretroviral treatment. These cocktails of reverse transcriptase inhibitors, protease inhibitors, and other types of HIV treatment may be prescribed individually. They can also be prescribed as multiple drugs combined in a single co-formulated pill.

There are no specific HAART drugs. It is the combination of classes that makes a regimen HAART.

Pronunciation: HAART is pronounced like "heart"

Alternate Spellings: drug cocktail, combination therapy, antiretroviral therapy, triple therapy

Some Examples of Highly Active Antiretroviral Therapy for HIV

HAART therapy can be done with a number of different drugs.

 Atripla is a single dose HAART regimen that contains two nucleoside inhibitors (emtricitabine and tenofovir) and one non-nucleoside inhibitor (efavirenz) to suppress the virus. Many doctors and patients like single-dose therapies. These pills make it much easier for patients to take their HAART drugs correctly. One pill, once or twice a day is easy to remember. Multiple pills on different schedules is much harder. 

Certain other combination pills may need to be prescribed with at least one other drug to attain the multiple mechanisms of action required for HAART. These may be harder to be adherent to, which can increase the risk of resistance.  For example, Truvada, which contains the two nucleoside reverse transcriptase inhibitors emtricitabine and tenofovir in a single pill, is usually prescribed with another drug. However, Truvada can be used alone for pre-exposure prophylaxis (PrEP). Although some people do worry about resistance developing during PrEP, it's less of an issue than during ongoing HAART therapy.

Did You Know? HAART Therapy is actually a redundant term. The T in HAART stands for treatment. Therefore, HAART therapy actually means "highly active antiretroviral treatment therapy. HAART can be used alone as a term. 


Blanco JL, Montaner JS, Marconi VC, Santoro MM, Campos-Loza AE, Shafer RW, Miller MD, Paredes R, Harrigan R, Nguyen ML, Perno CF, Gonzalez-Hernandez LA, Gatell JM. Lower prevalence of drug resistance mutations at first-line virological failure to first-line therap with atripla vs. tenofovir + emtricitabine/lamivudine + efavirenz administered on a multiple tablet therapy. AIDS. 2014 Nov 13;28(17):2531-9. doi: 10.1097/QAD.0000000000000424.

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