Comparative Pharmacology
Head-to-head clinical analysis: EMTRIVA versus LAMIVUDINE AND STAVUDINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMTRIVA versus LAMIVUDINE AND STAVUDINE.
EMTRIVA vs LAMIVUDINE AND STAVUDINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Nucleoside reverse transcriptase inhibitor; emtricitabine is phosphorylated to emtricitabine 5'-triphosphate which competes with deoxycytidine 5'-triphosphate for incorporation into viral DNA, resulting in chain termination.
Lamivudine is a nucleoside reverse transcriptase inhibitor (NRTI) that inhibits HIV-1 reverse transcriptase via DNA chain termination after intracellular phosphorylation to lamivudine triphosphate. Stavudine is also an NRTI that inhibits HIV-1 reverse transcriptase after phosphorylation to stavudine triphosphate.
Emtricitabine 200 mg orally once daily.
Lamivudine 150 mg and stavudine 30-40 mg (depending on body weight: <60 kg: stavudine 30 mg; ≥60 kg: stavudine 40 mg) orally twice daily.
None Documented
None Documented
Terminal elimination half-life ~10 hours (mean 10 h, range 7-14 h) in adults; prolonged in renal impairment (up to 90 h in severe impairment)
Lamivudine: Terminal half-life 5-7 hours (adults) to 10-12 hours (neonates); intracellular triphosphate half-life 10.5-15.5 hours, allowing once-daily dosing. Stavudine: Terminal half-life 1.0-1.6 hours but intracellular triphosphate half-life 3.5-4 hours, supporting twice-daily dosing.
Renal excretion of unchanged drug (~86%) by glomerular filtration and active tubular secretion; fecal excretion (<1%)
Lamivudine: Approximately 70% of dose excreted unchanged in urine via glomerular filtration and active tubular secretion; 5-10% as trans-sulfoxide metabolite; fecal excretion <10%. Stavudine: Approximately 40% of dose excreted unchanged in urine via glomerular filtration and active tubular secretion; remainder metabolized to thymine and other metabolites; renal excretion accounts for ~60% of elimination.
Category C
Category A/B
Antiretroviral, NRTI
NRTI