Comparative Pharmacology
Head-to-head clinical analysis: EMTRIVA versus STAVUDINE LAMIVUDINE EFAVIRENZ.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMTRIVA versus STAVUDINE LAMIVUDINE EFAVIRENZ.
EMTRIVA vs STAVUDINE; LAMIVUDINE; EFAVIRENZ
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.
Combination antiretroviral: stavudine is a nucleoside reverse transcriptase inhibitor (NRTI); lamivudine is an NRTI; efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI). Stavudine and lamivudine are phosphorylated intracellularly to active triphosphate metabolites that compete with natural substrates and incorporate into viral DNA, causing chain termination. Efavirenz binds directly to reverse transcriptase, causing allosteric inhibition and preventing RNA-dependent DNA polymerization.
Emtricitabine 200 mg orally once daily.
One tablet (stavudine 30 mg + lamivudine 150 mg + efavirenz 600 mg) orally once daily on an empty stomach, preferably at bedtime.
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)
Stavudine: 1.0-1.6 h (adults), 2.5-5.0 h (neonates). Lamivudine: 5-7 h (adults), 10-14 h (neonates). Efavirenz: 40-55 h (single dose), 52-76 h (multiple doses).
Renal excretion of unchanged drug (~86%) by glomerular filtration and active tubular secretion; fecal excretion (<1%)
Stavudine: 40% renal (unchanged), 60% biliary/fecal (metabolites). Lamivudine: 70% renal (unchanged), 30% fecal (metabolites). Efavirenz: 16-61% renal (metabolites), 14-34% fecal (unchanged).
Category C
Category A/B
Antiretroviral, NRTI
NRTI