What is the recommended Pre-Exposure Prophylaxis (PrEP) medication regimen for individuals at high risk of Human Immunodeficiency Virus (HIV) infection?

Recommended HIV Pre-Exposure Prophylaxis (PrEP) Regimens

The standard recommended regimen for HIV pre-exposure prophylaxis (PrEP) is daily oral Truvada (emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg) for all populations at high risk of HIV infection. 1

First-Line PrEP Options

Standard Daily Oral PrEP

• Tenofovir disoproxil fumarate (TDF) 300 mg/emtricitabine (FTC) 200 mg (Truvada) once daily is the primary recommended regimen for all populations 2, 1
• Efficacy exceeds 90% when adherence is high 3
• For MSM, a double dose (2 pills) of TDF/FTC is recommended on the first day 2

Alternative Dosing Strategies

• 2-1-1 (On-Demand) Dosing: Recommended only for men who have sex with men (MSM) 2, 1
  • 2 tablets 2-24 hours before sexual activity
  • 1 tablet 24 hours after the first dose
  • 1 tablet 48 hours after the first dose

Alternative Medications

• Tenofovir alafenamide (TAF)/emtricitabine: Recommended for MSM and transgender women who have or are at risk for kidney dysfunction, osteopenia, or osteoporosis 2, 1
• Injectable cabotegravir every 8 weeks is recommended (pending regulatory approval) for cisgender men and transgender women who have sex with men 2

Patient Selection and Screening

Pre-Initiation Assessment

• HIV testing: Combined HIV antibody and antigen testing (mandatory) 2, 1
  • HIV RNA testing if acute HIV is suspected
• Laboratory testing:
  • Serum creatinine level and estimated glomerular filtration rate 2, 1
  • Hepatitis B surface antigen 2, 1
  • Hepatitis C antibody 2, 1
  • Genital and non-genital STI screening 2, 1
  • Pregnancy testing for women 2, 1

Contraindications

• TDF-based PrEP is contraindicated in persons with creatinine clearance <60 mL/min/1.73m² 2, 1
• Not recommended during breastfeeding 2, 1

Monitoring Protocol

Follow-Up Schedule

• HIV testing: Every 2-3 months 2, 1
• Renal function:
  • Every 6 months for most patients 2, 1
  • More frequently (every 3-6 months) for patients >50 years or with comorbidities 2, 1
• STI screening: At least every 6 months, more frequently if symptomatic 2, 1
• Pregnancy testing: At each visit for women 2, 1

Prescription Guidelines

• Prescribe no more than a 90-day supply 2, 1
• Renew only after confirming HIV-negative status 2, 1

Special Considerations

Pregnancy

• TDF/FTC can be used during pregnancy if benefits outweigh risks 2, 1
• Safety data is incomplete, but no harm has been reported 2, 1

Adherence Support

• Adherence is crucial for PrEP efficacy 2, 1, 3
• Assess and address adherence barriers at each visit 2, 1

Management of HIV Diagnosis During PrEP

• If HIV infection is confirmed in someone using PrEP:
  • Start a recommended initial antiretroviral regimen 2
  • Perform resistance testing 2
  • Establish linkage to HIV care 2

Common Pitfalls to Avoid

• Starting PrEP without confirming HIV-negative status (can lead to resistance) 1
• Inadequate renal monitoring in patients with kidney dysfunction 1
• Using on-demand dosing in populations other than MSM 1
• Failing to provide comprehensive STI screening and treatment 2, 1
• Discontinuing PrEP too early after last exposure 1

TDF/FTC is highly effective and generally well-tolerated, with only about 2% of users discontinuing due to adverse effects 3. The medication's safety profile includes potential effects on renal function and bone mineral density, which necessitates appropriate monitoring 4.