Comparative Pharmacology
Head-to-head clinical analysis: EMTRICITABINE versus EMTRICITABINE AND TENOFOVIR ALAFENAMIDE FUMARATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMTRICITABINE versus EMTRICITABINE AND TENOFOVIR ALAFENAMIDE FUMARATE.
EMTRICITABINE vs EMTRICITABINE AND TENOFOVIR ALAFENAMIDE FUMARATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Nucleoside reverse transcriptase inhibitor; phosphorylated to emtricitabine triphosphate which competes with endogenous deoxycytidine triphosphate and incorporates into viral DNA causing chain termination.
Emtricitabine is a nucleoside reverse transcriptase inhibitor (NRTI) that is phosphorylated to emtricitabine triphosphate, which competes with the natural substrate deoxycytidine-5'-triphosphate and incorporates into viral DNA, causing chain termination. Tenofovir alafenamide is a nucleotide reverse transcriptase inhibitor (NtRTI) that is converted intracellularly to tenofovir diphosphate, which inhibits HIV-1 reverse transcriptase by competing with deoxyadenosine-5'-triphosphate and causing DNA chain termination.
200 mg orally once daily, typically in combination with other antiretroviral agents.
One tablet (emtricitabine 200 mg / tenofovir alafenamide fumarate 25 mg) orally once daily.
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
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).
Emtricitabine: terminal half-life ~10 hours; Tenofovir alafenamide: terminal half-life ~0.51 hours (rapid conversion to tenofovir); Intracellular tenofovir-diphosphate half-life >60 hours. Clinical context: daily dosing achieves steady state in 7 days.
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).
Emtricitabine: 86% excreted unchanged in urine, 14% as metabolites via urine. Tenofovir alafenamide: <1% excreted unchanged in urine; majority metabolized to tenofovir, which is eliminated renally via glomerular filtration and active tubular secretion. Overall, renal elimination is predominant.
Category C
Category A/B
Antiretroviral, NRTI
NRTI
"The risk or severity of adverse effects can be increased when Valganciclovir is combined with Emtricitabine."