Dosing and uses of Truvada (emtricitabine-tenofovir DF)
Adult dosage forms and strengths
emtricitabine/tenofovir DF (ie, tenofovir disoproxil fumarate)
tablet
- 200mg/300mg
HIV Infection
Indicated for HIV-infected individuals in combination with other antiretroviral agents
One 200 mg/300 mg tablet PO qDay
Pre-exposure Prophylaxis (CDC Guidelines)
Indication for pre-exposure prophylaxis (PrEP) in HIV-negative adults at high risk of acquiring HIV infection; for use in conjunction with other methods to avoid HIV infection
One 200 mg/300 mg tablet PO qDay
Recommendation based on CDC guidelines located at the following website - https://www.cdc.gov/hiv/pdf/prepguidelines2014.pdf
PrEP indications
- Men who have sex with men (MSM) at substantial lrisk of HIV acquisition
- Adult heterosexually active men and women at substantial risk of HIV acquisition
- Adult injection drug users (IDU) at substantial risk of HIV acquisition
- Heterosexually-active women and men whose partners are known to have HIV infection (ie, HIV-discordant couples) to protect the uninfected partner during conception and pregnancy so that an informed decision can be made in awareness of what is known and unknown about benefits and risks of PrEP for mother and fetus
Identifying individuals at high risk
- The following factors help to identify individuals at high risk for HIV:
- 1. Has partner(s) known to be HIV-1 infected, or
- 2. Engages in sexual activity within a high prevalence area or social network and 1 or more of the following:
- a) Inconsistent or no condom use
- b) Diagnosis or sexually transmitted infections
- c) Exchange of sex for commodities (eg, money, food, shelter, drugs)
- d) Illicit drug use or alcohol dependence
- e) Incarceration
- f) Partner(s) of unknown HIV-1 status with any of the risk factors listed above
Hepatitis B Treatment in HIV Coinfection or Resistant HBV
One 200 mg/300 mg tablet PO qDay
Dosage modifications
Renal impairment
- HIV infection
- CrCl ≥50 mL/min: Dose adjustment not necessary
- CrCl 30-49 mL/min: One 200 mg/300 mg tablet PO q48hr
- CrCl <30 mL/min: Do not administer
- Hemodialysis: Do not administer
- PrEP
- CrCl ≥60 mL/min or greater: Dose adjustment not necessary
- CrCl <60 mL/min: Do not use for pre-exposure prophylaxis
Hepatic impairment
- Dose adjustment not necessary in moderate-to-severe hepatic impairment
Dosing Considerations
Not recommended for use as a component of a triple nucleoside regimen
Should not be coadministered with combination products that are complete regimens or already contain emtricitabine or tenofovir (eg, Atripla, Complera, Emtriva, Genvoya, Odefsey, Stribild, Viread)
Do not coadminister with lamivudine-containing products (eg, Epivir, Combivir, Dutrebis, Epzicom, Triumeq, Trizivir) because of similarities between emtricitabine and lamivudine
In treatment experienced patients, use should be guided by laboratory testing and treatment history
Pediatric dosage forms and strengths
emtricitabine/tenofovir (ie, tenofovir disoproxil fumarate)
tablet
- 100mg/150mg
- 133mg/200mg
- 167mg/250mg
- 200mg/300mg
HIV Infection
Indicated in combination with other ART agents for HIV-1 infection children weighing at least 17 kg who can swallow the tablet whole
Weight <17 kg: Safety and efficacy not established
Weight ≥17 kg
- 17 to <22 kg: One 100 mg/150 mg tablet PO qDay
- 22 to <28 kg: One 133 mg/200 mg tablet PO qDay
- 28 to <35 kg: One 167 mg/250 mg tablet PO qDay
- ≥35 kg: One 200 mg/300 mg tablet PO qDay
Dosing Considerations
Not recommended for use as a component of a triple nucleoside regimen
Should not be coadministered with combination products that are complete regimens or already contain emtricitabine or tenofovir (eg, Atripla, Complera, Emtriva, Genvoya, Odefsey, Stribild, Viread)
Do not coadminister with lamivudine-containing products (eg, Epivir, Combivir, Dutrebis, Epzicom, Triumeq, Trizivir) because of similarities between emtricitabine and lamivudine
In treatment experienced patients, use should be guided by laboratory testing and treatment history
Truvada (emtricitabine-tenofovir DF) adverse (side) effects
>10%
Note: includes adverse effects of any severity rating
Diarrhea
Nausea
Fatigue
Headache
Dizziness
Depression
Insomnia
Abnormal dreams
Rash
1-10%
Note: includes adverse effects grade 2-4
Diarrhea (9%)
Nausea (9%)
Fatigue (9%)
Depression (9%)
Sinusitis (8%)
URI infections (8%)
Dizziness (8%)
Rash event (7%)
Headache (6%)
Nasopharyngitis (5%)
Insomnia (5%)
Vomiting (2%)
Warnings
Black box warnings
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases have been reported with the use of nucleoside analogues (including emtricitabine) alone or in combination with other antiretrovirals
Not FDA approved for the treatment of chronic hepatitis B virus (HBV) infection and the safety and efficacy of this drug have not been established in patients coinfected with HBV and HIV
Severe acute exacerbations of hepatitis B have been reported in patients coinfected with HIV-1 and HBV who have discontinued emtricitabine/tenofovir therapy
Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who discontinue therapy
Pre-exposure prophylaxis (PrEP)
- Use for PrEP must only be prescribed to individuals confirmed to be HIV-negative immediately prior to initiating and periodically (at least every 3 months) during use
- Drug-resistant HIV-1 variants have been identified with use of emtricitabine/tenofovir for a PrEP indication following undetected acute HIV-1 infection
- Do not initiate emtricitabine/tenofovir for PrEP if signs or symptoms of acute HIV-1 infection are present unless negative infection status is confirmed
Contraindications
Hypersensitivity
Do not use as PrEP in HIV-infected individuals or individuals with unknown HIV status
Use as monotherapy in HIV-infected patients
Cautions
Risk of potentially fatal lactic acidosis and severe hepatomegaly with steatosis with all NRTIs
Do not coadminister with other drugs containing emtricitabine or tenofovir
Severe exacerbation of hepatitis B may occur upon discontinuation
Risk of immune reconstitution syndrome
Redistribution/ accumulation of body fat observed in patients receiving antiretroviral therapy
Early virologic failure reported in HIV-infected patients; monitor and consider treatment modification
If clinical symptoms consistent with acute viral infection are present and recent (<1 month) exposures are suspected, delay starting PrEP for at least one month and reconfirm negative HIV-1 status or use a test approved by the FDA as an aid in the diagnosis of HIV-1 infection, including acute or primary HIV-1 infection; while receiving therapy for PrEP HIV-1 screening tests should be repeated at least every 3 months
Renal toxicity
- Increased risk of new onset or worsening renal impairment
- Estimate CrCl in all patients before initiating
- Routinely monitor calculated creatinine clearance and serum phosphorus
- Avoid use with CrCl <30 mL/min, hemodialysis, or concurrent or recent use of nephrotoxic drugs
Bone effects of tenofovir
- Bone mineral density may decrease
- Osteomalacia associated with proximal renal tubulopathy, manifested as bone pain or pain in extremities and which may contribute to fractures, have been reported
Pregnancy and lactation
Pregnancy category: B
Lactation: excretion in milk unknown/not recommended
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Truvada (emtricitabine-tenofovir DF)
Mechanism of action
Emtricitabine: Nucleoside Reverse Transcriptase Inhibitor (NRTI); following phosphorylation, interferes with HIV viral DNA polymerase and inhibits viral replication; cytosine analogue
Tenofovir: Nucleoside Reverse Transcriptase Inhibitor (NRTI); following hydrolysis and phosphorylation, inhibits HIV-1 reverse transcriptase by competing with AMP as substrate
Administration
Oral Administration
May take with or without food
Swallow tablet whole; do not chew, crush, break, or dissolve
