From the Guidelines
The recommended antiretroviral therapy regimen for HIV post-exposure prophylaxis (PEP) is a three-drug combination consisting of tenofovir disoproxil fumarate (TDF) plus emtricitabine (FTC) as the backbone, along with either dolutegravir (DTG) or raltegravir (RAL) as the third agent, as recommended by the International Antiviral Society-USA panel 1. This regimen should be started as soon as possible after exposure, ideally within 2 hours but no later than 72 hours, and continued for 28 days, as prompt initiation and completion of the full course are thought to be required to maximize the benefit of the intervention 1. The typical adult dosing is TDF 300mg/FTC 200mg (which can be given as Truvada, one tablet daily) plus either DTG 50mg once daily or RAL 400mg twice daily. Before starting PEP, baseline HIV testing should be performed, along with tests for hepatitis B, hepatitis C, and renal function. Follow-up testing for HIV should occur at 4 to 6 weeks, 3 months, and 6 months after exposure, although shorter follow-up (eg, 3 or 4 months) may be possible with a fourth-generation assay 1. Side effects may include nausea, fatigue, headache, and diarrhea, which can be managed symptomatically. This regimen is recommended because it provides broad antiretroviral coverage with medications that have high genetic barriers to resistance, good tolerability profiles, and can rapidly achieve therapeutic drug levels to prevent HIV from establishing infection in the body. Key considerations for PEP include:
- Starting the regimen as soon as possible after exposure
- Completing the full 28-day course of treatment
- Providing enhanced adherence counseling to support individuals initiating HIV PEP 1
- Monitoring patients for uncommon side effects and managing side effects symptomatically.
From the Research
Antiretroviral Therapy Regimens for Post-Exposure Prophylaxis (PEP)
The recommended antiretroviral therapy regimen for PEP after HIV exposure is a three-drug therapy, with a preferred regimen of tenofovir/emtricitabine and raltegravir, as recommended by the US Public Health Service and the New York State Department of Health 2.
Key Considerations for PEP Regimens
- The choice of regimen should be based on the individual's medical history, potential drug interactions, and the likelihood of adherence to the treatment protocol.
- Newer antiretroviral agents have demonstrated better tolerability, completion rates, and fewer drug-drug interactions compared to older regimens 2.
- The use of integrase strand transfer inhibitor-based regimens has become more widespread in HIV care 3.
Specific Regimens and Their Efficacy
- A study evaluating a novel 3-drug PEP regimen consisting of raltegravir, tenofovir DF, and emtricitabine found that none of the 100 participants enrolled became HIV infected, and the regimen was well-tolerated with mild side effects 4.
- Another study found that initiating pre-exposure or post-exposure prophylaxis in the setting of undiagnosed acute HIV could cause antiretroviral resistance, but rapid linkage to care and initiation of antiretroviral therapy can lead to durable viral suppression 5.
Role of Healthcare Providers in PEP
- Healthcare providers, including nurse practitioners, play an essential role in managing treatment for people exposed to HIV and following up on these patients' response and adherence to the treatment protocol 6.
- Providers should consider acute HIV screening when starting PEP, as undiagnosed acute HIV can occur in individuals prescribed PEP 5.