What is the recommended pre-exposure prophylaxis (PrEP) regimen for HIV prevention?

Recommended Pre-Exposure Prophylaxis (PrEP) Regimens for HIV Prevention

The recommended primary PrEP regimen for HIV prevention is daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC), with alternative options including emtricitabine/tenofovir alafenamide (TAF/FTC) for men who have sex with men and transgender women, and long-acting injectable cabotegravir administered at 8-week intervals. 1

Primary PrEP Regimen Options

First-Line Options:

• Daily oral TDF/FTC (Truvada): Standard regimen with proven efficacy across all populations 1
• TAF/FTC (Descovy): Approved for men who have sex with men (MSM) and transgender women 1
• Long-acting injectable cabotegravir: Administered at 8-week intervals 1

Alternative Options:

• Event-driven PrEP (2-1-1 dosing): May be considered for MSM and transgender women
  • Two tablets taken 2-24 hours before sex
  • One tablet 24 hours after the first dose
  • One tablet 48 hours after the first dose 2, 1
• Lamivudine/Tenofovir (3TC/TDF): Considered clinically interchangeable with FTC/TDF in resource-limited settings 3

Population-Specific Recommendations

Who Should Consider PrEP:

1. Men who have sex with men (MSM) who have:

   • At least one episode of condomless anal intercourse in past 6 months 2
   • Multiple sexual partners
   • MSM risk index score ≥10 2

2. Transgender women at high risk of HIV infection 2, 1

3. HIV-seronegative partners of HIV-infected persons who do not have viral suppression 1

4. People who inject drugs 1, 4

5. At-risk heterosexual men and women 1

Medication Selection Algorithm

For MSM and Transgender Women:

• First choice: Daily oral TDF/FTC or TAF/FTC 1
• If bone or renal concerns exist: TAF/FTC preferred 1, 5
• If intermittent sexual activity: Consider event-driven PrEP (2-1-1 dosing) 1

For Heterosexual Men and Women:

• Only option: Daily oral TDF/FTC 1
• TAF/FTC is not currently approved for this population

For People Who Inject Drugs:

• Only option: Daily oral TDF/FTC 1, 4

Monitoring Requirements

Before Starting PrEP:

• HIV testing with combination antigen-antibody assay
• Serum creatinine with estimated creatinine clearance
• Hepatitis B surface antigen testing
• Comprehensive STI screening 1

Follow-up Monitoring:

• HIV testing: Every 2-3 months
• Renal function: Every 3-6 months
• STI screening: Every 3 months
• Creatinine level testing: Every 6 months
• Pregnancy testing (for women): At each visit 1

Important Considerations

Adherence:

• Critical for efficacy - requires at least 4 of 7 doses per week for MSM and transgender women
• Heterosexual men and women and people who inject drugs require at least 6 of 7 doses per week 1

Contraindications:

• Active HIV infection
• Creatinine clearance <60 mL/min for TDF-based PrEP 1

Cautions:

• Osteopenia or osteoporosis (consider TAF/FTC)
• Chronic hepatitis B virus infection
• Pregnancy and breastfeeding (benefits may outweigh risks) 1

Special Situations

Recent HIV Exposure:

• If exposure occurred within 72 hours: Provide 3-drug post-exposure prophylaxis (PEP) for 1 month, then transition to 2-drug PrEP 1
• If exposure occurred >72 hours ago: Initiate standard PrEP protocol 1

Transitioning from PEP to PrEP:

• An immediate transition from nPEP to PrEP might be beneficial for persons with anticipated repeat or ongoing potential HIV exposures 2
• Complete HIV testing at the completion of the nPEP regimen with prompt transition to a recommended PrEP regimen 2

PrEP is a highly effective HIV prevention strategy when taken as prescribed, with efficacy strongly correlated with adherence 6. The selection of the appropriate regimen should consider the individual's specific risk factors, medical history, and likelihood of adherence to the prescribed regimen.