Recommended Use of Emtricitabine (Emtriva) in HIV Treatment
Emtricitabine is indicated for use in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and is not recommended as monotherapy. 1
Role in Antiretroviral Therapy
- Emtricitabine (200 mg once daily) serves as a key component of the nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) backbone in combination antiretroviral therapy regimens 2
- It is commonly paired with tenofovir (either as tenofovir disoproxil fumarate [TDF] or tenofovir alafenamide [TAF]) as part of preferred initial regimens 2
- Emtricitabine can be used interchangeably with lamivudine in most treatment regimens, as they have similar resistance profiles and efficacy 2
Recommended Combinations
First-line regimens containing emtricitabine include:
For patients with HIV/HBV coinfection, emtricitabine combined with TDF or TAF is recommended due to activity against both viruses 2
Dosing and Administration
- The standard dose is one 200 mg capsule taken orally once daily, with or without food 1
- Dose adjustment is required in patients with renal impairment 1:
- CrCl ≥50 mL/min: 200 mg every 24 hours
- CrCl 30-49 mL/min: 200 mg every 48 hours
- CrCl 15-29 mL/min: 200 mg every 72 hours
- CrCl <15 mL/min or on hemodialysis: 200 mg every 96 hours (if on hemodialysis, administer after dialysis session)
Monitoring Recommendations
- Prior to initiating emtricitabine, patients should undergo HIV RNA testing, CD4 cell count, HIV genotype testing, HLA-B*5701 testing (if considering abacavir), and screening for co-infections 2
- After starting therapy, HIV RNA levels should be monitored within the first 6 weeks, then every 3 months until <50 copies/mL for 1 year, then every 6 months 2
- CD4 cell count should be monitored every 6 months until >250/μL for 1 year, then can be stopped as long as virus is suppressed 2
Prevention Use (PrEP)
- Emtricitabine/tenofovir disoproxil fumarate is recommended for pre-exposure prophylaxis (PrEP) in populations at high risk for HIV acquisition 2
- Daily TDF/emtricitabine is the recommended PrEP regimen for men and women at risk of sexual exposure and people who inject drugs 2
- For MSM with infrequent sexual exposures, pericoital TDF/emtricitabine (2-1-1 dosing) may be considered as an alternative to daily dosing 2
- TDF/emtricitabine should continue for 1 week after the last sexual exposure when discontinuing PrEP 2
Special Considerations
- Warning: Severe acute exacerbations of hepatitis B have been reported in patients coinfected with HIV-1 and HBV who have discontinued emtricitabine 1
- Hepatic function should be closely monitored in patients coinfected with HIV-1 and HBV who discontinue emtricitabine 1
- Emtricitabine is not recommended as monotherapy due to the high risk of resistance development 1
- Lactic acidosis and severe hepatomegaly with steatosis are potential serious adverse effects; treatment should be discontinued if these develop 1
Adverse Effects
- Most common adverse reactions (≥10%) include headache, diarrhea, nausea, fatigue, dizziness, depression, insomnia, abnormal dreams, rash, abdominal pain, asthenia, increased cough, and rhinitis 1
- Skin hyperpigmentation is very common (≥10%) in pediatric patients 1
- Emtricitabine has a favorable safety profile compared to some other NRTIs 3, 4
By following these recommendations for emtricitabine use in HIV treatment, clinicians can optimize patient outcomes while minimizing adverse effects and the development of resistance.