Comparative Pharmacology
Head-to-head clinical analysis: EFAVIRENZ LAMIVUDINE TENOFOVIR DISOPROXIL FUMARATE versus EMTRICITABINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EFAVIRENZ LAMIVUDINE TENOFOVIR DISOPROXIL FUMARATE versus EMTRICITABINE.
EFAVIRENZ; LAMIVUDINE; TENOFOVIR DISOPROXIL FUMARATE vs EMTRICITABINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that binds to reverse transcriptase and blocks RNA-dependent and DNA-dependent DNA polymerase activities. Lamivudine is a nucleoside reverse transcriptase inhibitor (NRTI) that inhibits HIV reverse transcriptase via DNA chain termination. Tenofovir disoproxil fumarate is a nucleotide reverse transcriptase inhibitor (NtRTI) that competes with natural substrates and causes DNA chain termination after phosphorylation to tenofovir diphosphate.
Nucleoside reverse transcriptase inhibitor; phosphorylated to emtricitabine triphosphate which competes with endogenous deoxycytidine triphosphate and incorporates into viral DNA causing chain termination.
One tablet (efavirenz 600 mg, lamivudine 300 mg, tenofovir disoproxil fumarate 300 mg) orally once daily on an empty stomach (preferably at bedtime to reduce CNS side effects).
200 mg orally once daily, typically in combination with other antiretroviral agents.
None Documented
None Documented
Clinical Note
moderateEmtricitabine + Ribavirin
"Emtricitabine may increase the hepatotoxic activities of Ribavirin."
Clinical Note
moderateLamivudine + Emtricitabine
"The risk or severity of adverse effects can be increased when Lamivudine is combined with Emtricitabine."
Clinical Note
moderateGanciclovir + Emtricitabine
"The risk or severity of adverse effects can be increased when Ganciclovir is combined with Emtricitabine."
Clinical Note
moderateValganciclovir + Emtricitabine
Efavirenz: 40-55 hours (single dose), 52-76 hours (multiple doses); Lamivudine: 5-7 hours; Tenofovir: 12-18 hours (prolonged to 24-30 hours when co-administered with efavirenz).
Terminal elimination half-life is approximately 10 hours (range 8–12 hours) in adults with normal renal function; prolonged to >20 hours in severe renal impairment (CrCl <30 mL/min).
Efavirenz: 14-34% unchanged in urine, 16-61% as metabolites in feces; Lamivudine: ~70% unchanged in urine via glomerular filtration and active tubular secretion; Tenofovir disoproxil fumarate: 70-80% unchanged in urine via glomerular filtration and active tubular secretion.
Renal: approximately 86% of the dose is excreted unchanged in urine via glomerular filtration and active tubular secretion. Biliary/fecal: minimal (<14% as unchanged drug and metabolites in feces).
Category A/B
Category C
NRTI
Antiretroviral, NRTI
"The risk or severity of adverse effects can be increased when Valganciclovir is combined with Emtricitabine."