Pre-Prescription Assessment

Specific pre-prescription laboratory testing should be performed prior to prescribing PrEP with either TAF/FTC or TDF/FTC (Table 3).29,30 Treatment of HIV infection requires a minimum of 2 different drug classes; therefore administering only TAF/FTC or TDF/FTC to a person with confirmed HIV infection can lead to drug resistance. This is one of the main reasons why it is important for clinicians to confirm a person’s HIV status prior to placing them on PrEP.23 An individual found to have HIV infection at baseline should be offered 1 of the recommended combination HIV antiretroviral therapy options based on the current CDC HIV treatment guidelines.23

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The components of TAF/FTC and TDF/FTC have activity against hepatitis B virus (HBV). When persons with chronic HBV infection are prescribed TDF/FTC or TAF/FTC, these agents will also have an effect on the HBV. Therefore, it is important to check the HBV status of any person with HIV prior to initiating therapy and monitor their liver function as there is risk for a flare of HBV infection following discontinuation of PrEP.23

Patients who are prescribed PrEP should be followed up at a minimum of every 3 months to monitor their HIV status. At each follow-up visit, clinicians should assess for any adherence issues, screen for STIs as appropriate, and periodically assess the need for ongoing PrEP. Renal function should also be assessed at least every 6 months in these patients.23

On-Demand or Event-Driven PrEP

For MSM who may not be at continuous risk for HIV but who still want to benefit from PrEP, the use of on-demand dosing (also known as “event-driven” or “2-1-1” dosing) may be considered.31 With on-demand dosing, individuals take 2 tablets of TDF/FTC between 2 and 24 hours prior to a sexual encounter and then continue taking an additional dose every 24 hours until there has been 2 consecutive days without sex. This regimen has been studied in several trials and is recommended by the World Health Organization, as well as the New York City and San Francisco Departments of Health.31-33 On-demand dosing is not recommended for individuals with chronic HBV infection.

Non-Occupational Post-Exposure Prophylaxis (nPEP)

For individuals not on PrEP but who experience an exposure that puts them at risk for HIV infection, nPEP may be considered. nPEP should be started as soon as possible after exposure but not later than 72 hours after exposure.30 Baseline laboratory testing should be obtained and is similar to baseline testing for PrEP (Table 3). However, clinicians should not defer or delay starting nPEP if laboratory testing or results are not available prior to the first dose.30

Current guidelines for nPEP recommend a combination of TDF 300 mg/FTC 200 mg plus an integrase strand transfer inhibitor, either raltegravir 400 mg twice daily or dolutegravir 50 mg once daily (Table 4).30 The nPEP regimen should be taken for 28 days following an exposure. Clinicians should assess if individuals currently on nPEP would benefit from PrEP. If so, at the conclusion of the 28-day regimen, clinicians can transition individuals to PrEP with once-daily TDF/FTC or TAF/FTC.30

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Follow-up antibody/antigen testing should be performed 4 to 6 weeks after initial exposure, with additional testing recommended 3 and 6 months post-exposure.30 If the person presents with signs or symptoms consistent with acute HIV infection (eg, fever, malaise, mononucleosis-like symptoms), the clinician should consider assessing HIV RNA viral load.34 All individuals on nPEP should be counseled to use additional protective barriers, such as condoms, until HIV status can be confirmed to avoid the possibility of transmission of HIV to others.30

Substance Use

MSM who use substances, such as crystal methamphetamine, are at increased risk of acquiring HIV.34 Clinicians should screen for substance use and provide appropriate referrals or support for treatment. Interventions such as motivational interviewing and cognitive behavioral therapy have demonstrated some benefit in this setting.35 Persons who report ongoing substance use should be offered PrEP to minimize the risk of HIV infection.23

Related Articles


MSM remain a population at increased risk of acquiring HIV infection. One of the primary barriers to receiving appropriate HIV prevention services among MSM is a lack of culturally competent providers. Nurse practitioners and physician assistants can play a vital role in the assessment of these individuals, providing counseling about ways to minimize or prevent HIV and offering access to interventions proven to reduce the risk of acquiring HIV. By providing care that is culturally affirmative, clinicians can help address the disparity of HIV infection among MSM and help achieve the national goal of reducing the number of new HIV infections by 90% by 2030.1

Jeffrey Kwong, DNP, MPH, ANP-BC, AAHIVS, FAANP, is a professor in the Division of Advanced Nursing Practice in the School of Medicine at Rutgers, The State University of New Jersey.


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