Meaning of HAART: The combination approach that turned HIV infection from a fatal illness into a manageable long-term condition.

Definition of HAART

HAART stands for highly active antiretroviral therapy, the practice of treating HIV with several antiretroviral drugs together rather than one at a time. Combining agents that block different steps of the viral life cycle suppresses copying so completely that the virus falls below the level standard blood tests can detect. The immune system then recovers and rebuilds its supply of CD4 cells.

Why combine drugs?

HIV copies its genetic material carelessly, introducing errors with almost every new particle. Among the countless variants produced each day, some already carry a change that makes one drug ineffective. Give that drug alone and it clears away the rest, leaving the resistant variants to take over within weeks. A virus would have to carry several independent changes at once to escape three drugs acting on different steps, and that combination is rare enough that suppression holds. This is the whole logic of antiretroviral therapy.

What classes are combined?

ClassStep it blocks
Entry and fusion inhibitorsGetting into the cell
Reverse transcriptase inhibitorsCopying viral RNA into DNA
Integrase inhibitorsStitching that DNA into the cell's own
Protease inhibitorsCutting new proteins into working parts

Is the term still used?

Less and less. It was coined to mark the difference between the new combinations and the single-drug treatment that preceded them. Since every current regimen is highly active by that standard, the qualifier no longer distinguishes anything, and the plain term antiretroviral therapy has replaced it. HAART now appears mainly in older literature and in the names of long-running studies.

What does treatment achieve?

Suppression is not cure. The virus persists in resting cells that treatment cannot reach, and stopping the drugs allows it to return. What treatment does achieve is substantial: it halts damage to the immune system, prevents progression to AIDS, restores CD4 counts, and brings life expectancy close to that of the general population when started early and taken consistently. It also prevents onward transmission, since a person whose virus is reliably undetectable does not pass HIV to a sexual partner. Modern regimens are frequently a single daily tablet containing the whole combination.

Also known as

ARThighly active antiretroviral therapy

Used in a sentence

The notes recorded that HAART had been started shortly after the diagnosis was confirmed.

+

Good to know

The term has largely been replaced by antiretroviral therapy, since every current regimen meets the standard the word highly active was coined to mark.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.