HIV antiretroviral therapy (ART)
Antiretroviral therapy (ART) combines three or more drugs from at least two classes to suppress HIV replication. First-line therapy is bictegravir/emtricitabine/tenofovir alafenamide or dolutegravir-based triple therapy, started as soon as the patient is ready regardless of CD4 count, and continued for life to prevent AIDS and transmission.
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What this article covers
- Overview
Definition: antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection combines three or more drugs from at least two mechanistic classes, usually two nucleoside reverse…
- Epidemiology
Treatment cascade gap: most ongoing transmission comes from persons undiagnosed or diagnosed but not retained in care, causing an estimated 80% of new US HIV transmissions in 2016.
- Risk factors
Baseline transmitted resistance: 10% to 20% of treatment-naive patients carry a transmitted resistance mutation, why genotype testing is sent even though it does not delay starting.
- Pathophysiology
Viral entry: HIV glycoprotein gp120 binds CD4 and a coreceptor, C-C chemokine receptor type 5 (CCR5) or CXCR4; maraviroc blocks CCR5, reserved for salvage regimens.
- Clinical features
Virologic response: plasma HIV RNA falls rapidly within the first weeks of an effective regimen and should become undetectable, rechecked 1 month after starting or switching therapy.
- Differential diagnosis
Bictegravir/emtricitabine/tenofovir alafenamide versus dolutegravir/lamivudine/tenofovir disoproxil fumarate: both preferred, but the bictegravir tablet uses tenofovir alafenamide with less renal and…
- Diagnosis
Confirmatory testing establishes eligibility: HIV infection is established by a reactive antigen/antibody immunoassay confirmed with an HIV-1/HIV-2 differentiation immunoassay or HIV RNA testing; a…
- Management
Start without delay: begin ART regardless of CD4 count; same-day or within-2-week initiation improves suppression and proceeds before genotype results return, except active cryptococcal meningitis…
- Complications
Class-wide nucleoside risk: every NRTI carries a labeled lactic acidosis risk, far more common with older agents than with those used today.
- Prognosis
Life expectancy: with sustained suppression, life expectancy approaches that of the general population.
- Prevention
Pre-exposure prophylaxis: tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg orally once daily cuts acquisition risk by more than 90% with consistent adherence; tenofovir alafenamide 25…
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