From the Guidelines
Zidovudine (AZT) should not be used as the first-line treatment for post-exposure prophylaxis (PEP) after HIV exposure, due to its side effect profile and the availability of better-tolerated alternatives, such as tenofovir-based regimens, as recommended by the most recent guidelines 1. When considering PEP, it is crucial to initiate treatment as soon as possible, preferably within 72 hours post-exposure, to maximize the benefit of the intervention. The optimal duration of PEP is 28 days, and adherence to the full course is essential for effectiveness. Some key points to consider when prescribing PEP include:
- Prompt initiation of treatment, with the goal of starting within hours of exposure
- Completion of the full 28-day course of antiretroviral drugs
- Use of well-tolerated regimens, such as those based on tenofovir, to minimize side effects and improve adherence
- Enhanced adherence counseling to support individuals in completing the full course of treatment
- Consideration of the individual's specific situation, including potential contraindications or allergies to certain medications, when selecting a PEP regimen. It is also important to note that the most recent guidelines, such as those from the World Health Organization 1, provide recommendations for PEP prescribing and adherence support, and should be consulted when making decisions about PEP.
From the Research
Role of Zidovudine (AZT) in Post-Exposure Prophylaxis (PEP)
- Zidovudine (AZT) is an antiretroviral medication that has been used in the past for post-exposure prophylaxis (PEP) after human immunodeficiency virus (HIV) exposure 2.
- However, current guidelines recommend a 28-day course of antiretroviral therapy (ART) within 36-72 hours of exposure to HIV, and AZT is no longer the preferred choice due to its side effects and the availability of better-tolerated alternatives 3, 4.
Alternative Regimens for PEP
- Several alternative regimens have been studied for PEP, including tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC)/rilpivirine (RPV) 5, tenofovir/emtricitabine and lopinavir/ritonavir tablet formulation (TDF/FTC+LPV/r) 4, and coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) 6.
- These regimens have shown good tolerability and efficacy in preventing HIV seroconversion, and are considered as alternatives to AZT-based regimens.
Safety and Tolerability of PEP Regimens
- The safety and tolerability of PEP regimens are crucial factors in determining their effectiveness, as poor tolerability can lead to non-adherence and reduced efficacy 6, 5, 4.
- Studies have shown that regimens such as TDF/FTC/RPV and BIC/FTC/TAF have better tolerability profiles compared to AZT-based regimens, with lower rates of side effects and discontinuations due to adverse events.