Classes
DEA Class; Rx
Common Brand Names; Symfi, Symfi Lo
- HIV, ART Combos
Description
Tenofovir: NRTI; following hydrolysis and phosphorylation, inhibits HIV-1 reverse transcriptase by competing with AMP as substrate
Lamivudine: NRTI; following phosphorylation, inhibits HIV reverse transcriptase by viral DNA chain termination; cytosine analog
Efavirenz: NNRTI; activity against HIV-1 by binding to reverse transcriptase and consequently blocking the RNA-dependent and DNA-dependent DNA polymerase activities including HIV-1 replication; it does not require intracellular phosphorylation for antiviral activity
Indications
Indicated as a complete antiretroviral (ART) regimen for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in adults and children (weight dependent)
Combination consists of 2 nucleo(t)side reverse transcriptase inhibitors (NRTIs) (ie, lamivudine and tenofovir) and 1 non-nucleoside reverse transcriptase inhibitor (NNRTI) (ie, efavirenz)
Contraindications
Documented hypersensitivity (eg, Stevens-Johnson syndrome, erythema multiforme, toxic skin eruptions) to any components contained in the formulation
Coadministration with elbasvir and grazoprevir
Adverse Effects
Rash (18%)
Headache (14%)
Pain (13%)
Diarrhea (11%)
Depression (11%)
Fasting cholesterol >250 mg/dL (19%)
Creatine kinase (males: >990 U/L; females >845 U/L) (12%)
Fever (8%)
Abdominal pain (7%)
Asthenia (6%)
Anxiety (6%)
Arthralgia (5%)
Insomnia (5%)
Pneumonia (5%)
Myalgia (3%)
Dizziness (3%)
Lipodystrophy (1%)
Peripheral neuropathy (1%)
Warnings
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, reported with the use of nucleoside analogs and other ARTs; suspend treatment in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity
Not approved for chronic hepatitis B virus (HBV) infection and the safety and efficacy have not been established in patients coinfected with HBV and HIV-1; if treatment with Epivir-HBV, tenofovir DF, or a tenofovir AF-containing product is prescribed for chronic hepatitis B for a patient with unrecognized or untreated HIV-1 infection, rapid emergence of HIV-1 resistance is likely to result because of the subtherapeutic dose and the inappropriateness of monotherapy HIV-1 treatment (see Black Box Warnings and Dosing Considerations)
Pregnancy and Lactation
Advise pregnant women of the potential risk to a fetus
The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV-1 infection
Efavirenz has been shown to pass into human breast milk; no information available on the effects of efavirenz on the breastfed infant or the effects of efavirenz on milk production
Lamivudine is excreted into human milk
Maximum Dosage
1 tablet (efavirenz 400 mg/lamivudine 300 mg/tenofovir DF 300 mg) PO qHS OR
1 tablet (efavirenz 600 mg/lamivudine 300 mg/tenofovir DF 300 mg) PO qHS
Clinical trials did not include sufficient number of patients aged ≥65 yr to determine if they respond differently from younger individuals
Exercise caution when administering lamivudine in elderly patients because of the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy
How supplied
efavirenz/lamivudine/tenofovir DF (ie, tenofovir disoproxil fumarate)
tablet
- 400mg/300mg/300mg (Symfi Lo)
- 600mg/300mg/300mg (Symfi)