What is the recommended Post-Exposure Prophylaxis (PEP) regimen for HIV exposure?

From the Guidelines

The recommended Post-Exposure Prophylaxis (PEP) regimen for HIV exposure is a 28-day course of three antiretroviral medications, typically consisting of tenofovir disoproxil fumarate (TDF) 300mg plus emtricitabine (FTC) 200mg once daily, combined with either raltegravir 400mg twice daily or dolutegravir 50mg once daily, as recommended by the most recent and highest quality study 1.

Key Considerations

• PEP should be initiated as soon as possible after exposure, ideally within 72 hours, as effectiveness decreases with delayed administration 1.
• The complete regimen requires baseline HIV testing before starting, with follow-up testing at 4-6 weeks and 3 months post-exposure 1.
• Side effects may include nausea, fatigue, and headache, which can be managed symptomatically.
• Adherence to the full 28-day course is crucial for effectiveness.

Mechanism of Action

• PEP works by preventing HIV from establishing infection in the body by inhibiting viral replication through different mechanisms:
  • Nucleoside reverse transcriptase inhibitors (TDF/FTC) block viral DNA synthesis.
  • Integrase strand transfer inhibitors (raltegravir/dolutegravir) prevent integration of viral DNA into host cells.

Patient Advice

• Patients should be advised to use barrier protection during sexual activity until follow-up testing confirms HIV-negative status.
• Ongoing discussions about adherence are recommended, especially in the absence of proven PrEP adherence interventions 1.

From the Research

Recommended PEP Regimens

The recommended Post-Exposure Prophylaxis (PEP) regimens for HIV exposure are as follows:

• Tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC)/rilpivirine (RPV) as a single-tablet regimen, once daily for 28 days 2
• Elvitegravir/cobicistat/tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) as a single daily pill for 28 days 3
• Raltegravir, tenofovir DF, and emtricitabine as a 3-drug regimen for PEP 4
• Dolutegravir with tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) as a 3-drug PEP regimen 5

Efficacy and Safety

These regimens have been shown to be safe and well-tolerated, with high completion rates and no reported cases of HIV seroconversion:

• The TDF/FTC/RPV regimen had a completion rate of 86.1% and no HIV seroconversion occurred at week 16 2
• The elvitegravir/cobicistat/TDF/FTC regimen had a completion rate of 71% and no participants became HIV infected 3
• The raltegravir, tenofovir DF, and emtricitabine regimen had a completion rate of 57% and none of the participants became HIV infected 4
• The dolutegravir with TDF-FTC regimen had a completion rate of 90% and no participant acquired HIV through week 12 5

Adverse Events

Common adverse events reported with these regimens include:

• Nausea or vomiting
• Diarrhea
• Headache
• Fatigue
• Abdominal symptoms
• Most of these adverse events were mild and did not result in medication discontinuation 2, 3, 4, 5