Intelence (Etravirine)

Intelence (etravirine) is used as part of antiretroviral therapy for HIV‑1 infection.

• HIV‑1 infection: reduces plasma HIV RNA levels and helps maintain immune function when used with a backbone regimen.
• Treatment‑experienced HIV‑1 patients: provides an option for individuals with resistance to other NNRTIs, improving virologic control.
• Combination antiretroviral therapy: contributes to a multi‑drug regimen that achieves sustained viral suppression.

• Etravirine binds to a non‑nucleoside site on the HIV‑1 reverse transcriptase enzyme, causing a conformational change that inhibits both RNA‑dependent and DNA‑dependent DNA polymerase activities. This blockade prevents the transcription of viral RNA into DNA and the subsequent integration of the viral genome into host cells, thereby halting replication of HIV‑1. The inhibition is reversible and selective, allowing normal host polymerases to function while specifically targeting the viral enzyme.

Etravirine may cause a range of adverse reactions, which are generally categorized by frequency and severity.

Common Side Effects

• Rash: mild to moderate skin eruptions, often pruritic.
• Nausea: transient feeling of stomach upset.
• Headache: mild to moderate intensity.
• Diarrhea: loose stools, usually self‑limiting.

Serious or Rare Side Effects

• Stevens‑Johnson syndrome/toxic epidermal necrolysis: severe skin detachment requiring immediate medical attention.
• Hepatic toxicity: elevated liver enzymes or hepatitis, potentially leading to liver dysfunction.
• Severe hypersensitivity reactions: including anaphylaxis, angioedema, or severe rash.

When prescribing etravirine, clinicians should consider several precautionary measures to ensure safe use.

• Pregnancy: Category B – use only if potential benefit justifies potential risk to fetus.
• Breastfeeding: Not recommended; drug may be excreted in breast milk.
• Hepatic impairment: Monitor liver function tests; dose adjustment may be required.
• Concomitant QT‑prolonging agents: Caution due to potential additive cardiac effects.
• Resistance testing: Perform baseline HIV‑1 genotype to assess susceptibility.
• Store at ambient temperature: Keep tablets below 25 °C in the original container, protect from moisture and direct sunlight.

Etravirine interacts with several medicines, influencing its plasma levels or the efficacy of co‑administered drugs.

Major Interactions (Avoid)

• Rifampin: strong inducer of CYP3A4, markedly reduces etravirine exposure; avoid co‑administration.
• St. John’s wort: induces CYP3A4, leading to decreased etravirine concentrations; avoid.
• Protease inhibitors boosted with ritonavir: may increase etravirine levels, requiring dose adjustment; avoid without monitoring.

Moderate Interactions (Monitor Closely)

• Other NNRTIs (e.g., efavirenz, nevirapine): may increase risk of hepatotoxicity; monitor liver enzymes.
• Antacids containing aluminum or magnesium: may reduce absorption; separate dosing by at least 2 hours.
• Warfarin: potential alteration of INR; monitor coagulation parameters.