Maraviroc

Maraviroc is used in the management of HIV‑1 infection, specifically targeting viruses that utilize the CCR5 co‑receptor.

• HIV‑1 infection (CCR5‑tropic): reduces viral load when combined with other antiretroviral agents.
• Treatment‑experienced HIV‑1 infection: provides an alternative mechanism of action for patients with resistance to other classes.
• Combination antiretroviral therapy: contributes to overall virologic suppression as part of a multi‑drug regimen.

• Maraviroc selectively binds to the CCR5 chemokine receptor on the surface of CD4+ T‑cells and macrophages, blocking the binding site used by R5‑tropic HIV‑1 strains. By preventing the interaction between the viral envelope glycoprotein gp120 and the CCR5 co‑receptor, the drug inhibits viral entry into host cells, thereby halting replication and spread of the virus.

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

Common Side Effects

• Headache
• Nausea
• Diarrhea
• Fatigue
• Cough
• Abdominal pain

Serious or Rare Side Effects

• Severe liver injury
• Allergic reactions such as rash or Stevens‑Johnson syndrome
• QT interval prolongation
• Pancreatitis
• Severe skin reactions including toxic epidermal necrolysis
• Immune reconstitution inflammatory syndrome

When prescribing Maraviroc, clinicians should observe several precautionary measures to ensure safe use.

• Assess CCR5 tropism before initiating: confirm virus uses CCR5 co‑receptor.
• Monitor liver function tests: baseline and periodic assessments recommended.
• Review concomitant medications: avoid strong CYP3A4 inhibitors or inducers.
• Observe for hypersensitivity reactions: discontinue if rash or anaphylaxis occurs.
• Store at ambient temperature below 25 °C: keep in original packaging, protect from moisture.

Maraviroc interacts with several medicines, requiring attention to avoid reduced efficacy or increased toxicity.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ritonavir, clarithromycin): may raise Maraviroc plasma concentrations.
• Strong CYP3A4 inducers (e.g., rifampin, carbamazepine): may lower Maraviroc levels and compromise effectiveness.

Moderate Interactions (Monitor Closely)

• H2‑blockers or antacids containing aluminum/magnesium: may affect absorption, monitor levels.
• Other antiretrovirals (e.g., protease inhibitors): dose adjustments may be required.
• Statins metabolized by CYP3A4 (e.g., simvastatin): increased risk of statin‑related toxicity, consider alternative lipid‑lowering agents.