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Pre-Exposure Prophylaxis (PrEP)
Prepared by Rachel Porth, M22, Tufts University School of Medicine (December 2019)

 

Truvada is the brand name for a pre-exposure prophylaxis (PrEP) oral antiretroviral medication consisting of tenofovir disoproxil fumarate and emtricitabine (TDF-FTC). It works by blocking HIV reverse transcriptase, which prevents the conversion from RNA to DNA. It can be prescribed by any licensed prescriber. The purpose of the medication is to prevent someone who is HIV-negative from getting HIV.  Once someone starts taking Truvada it takes 7 days to reach maximum protection from HIV for receptive anal sex, and 20 days for receptive vaginal sex and injection drug use.

 

Guidelines: USPSTF grade A recommendation to persons at high risk of HIV acquisition

High Risk individuals who should be assessed for PrEP include:

 

CDC Indications:

Recommended Indications for PrEP
Men Who have Sex with Men Hetorosexual Women and Men People Who Inject Drugs
  • Adult or adolescent male weighing at least 35kg (77 lbs)
  • Without acute or established HIV infections
  • Any male sex partners in past 6 months (if also sex with women, see next box)
  • Not in a monogamous partnership with a recently tested, HIV-negative man

AND at least of the following

  • Any anal sex without condoms (receptive or insertive) in past 6 months
  • A bacterial STI (syphilis, gonorrhea or chlamydia) diagnosed or reported in past 6 months
  • Adult or adolescent person weighing at least 35kg (77 lbs)
  • Without acute or established HIV infections
  • Any sex with opposite sex partners in past 6 months 
  • Not in a monogamous partnership with a recently tested, HIV-negative partner

AND at least one of the following

  • Is a man who has sex with both women and men (behaviorally bisexual) [also evaluate indications for PrEP use by previous box criteria]
  • infrequently uses condoms during sex with 1 or more partners of unknown HIV status who are known to be at substantial risk of HIV infection (PWID or bisexual male partner)
  • Is in an ongoing sexual relationship with an HIV-positive partner
  • A bacterial STI (syphilis, gonorrhea in women or men diagnosed or reported in past 6 months)
  • Adult or adolescent male weighing at least 35kg (77 lbs)
  • Without acute or established HIV infections
  • Any sex with opposite sex partners in past 6 months 
  • Any injection of drugs not prescribed by a clinician in past 6 months

AND at least one of the following

  • Any sharing of injection or drug preparation equipment in past 6 months
  • risk of sexual acquisition (also evaluate by criteria in previous boxes)

 

Effectiveness:

Downsides:

Potential side effects:

Conclusion:

Truvada is effective at preventing HIV infection if taken daily. However, it does require monitoring by a physician, does not prevent other STIs, and may come with potential side effects. A patient who is healthy, has no history of HIV infection, and is willing to comply with medication dosing and physician follow up should be assessed for Truvada.

Additional Resources:

Click on this link for a short PrEP quickstart guide for yourself, or your preceptor.

Click on this link for a slightly more in-depth guide to prescribing PrEP, and frequency of follow up visits and testing.

 

Sources:

-Anderson, P. L., Glidden, D. V., Liu, A., Buchbinder, S., Lama, J. R., Guanira, J. V., ... & Veloso, V. G. (2012). Emtricitabine-tenofovir concentrations and pre-exposure prophylaxis efficacy in men who have sex with men. Science translational medicine4(151), 151ra125-151ra125.

-Centers for Disease Control and Prevention. (2019). Prescribe PrEP Pre-Exposure Prophylaxis FAQs for the Health Care Professional. Retrieved from https://www.cdc.gov/stophivtogether/library/prescribe-hiv-prevention/brochures/cdc-lsht-php-brochure-prep-faq.pdf

-DynaMed [Internet]. Ipswich (MA): EBSCO Information Services. 1995 - . Record No. T907614Emtricitabine/Tenofovir; [updated 2018 Nov 06, cited 2019 Oct 21]. Available from https://www.dynamed.com/topics/dmp~AN~T907614. Registration and login required.

Author(s): Rachel Porth
Created: Wednesday December 4, 2019
Modified: Monday April 6, 2020

Copyright Information: Copyright 2019, Tufts University

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