Comparative Pharmacology
Head-to-head clinical analysis: ABACAVIR AND LAMIVUDINE versus EMTRIVA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ABACAVIR AND LAMIVUDINE versus EMTRIVA.
ABACAVIR AND LAMIVUDINE vs EMTRIVA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Abacavir is a carbocyclic synthetic nucleoside analogue. Intracellularly, it is phosphorylated to carbovir triphosphate, an analogue of deoxyguanosine-5'-triphosphate (dGTP). Carbovir triphosphate inhibits the activity of HIV-1 reverse transcriptase (RT) by competing with the natural substrate dGTP and by incorporating into viral DNA, causing chain termination. Lamivudine is a synthetic nucleoside analogue. Intracellularly, it is phosphorylated to lamivudine triphosphate, which inhibits HIV-1 RT via DNA chain termination after incorporation into viral DNA. Both drugs are nucleoside reverse transcriptase inhibitors (NRTIs).
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.
One tablet (600 mg abacavir/300 mg lamivudine) orally once daily.
Emtricitabine 200 mg orally once daily.
None Documented
None Documented
Abacavir: ~1.5 h; Lamivudine: 5–7 h in adults, prolonged to ~9 h in children. Clinically, twice-daily dosing maintains therapeutic concentrations.
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)
Abacavir: 83% renal (primarily as metabolites via alcohol dehydrogenase and glucuronidation), 16% fecal. Lamivudine: ~70% renal as unchanged drug via active tubular secretion.
Renal excretion of unchanged drug (~86%) by glomerular filtration and active tubular secretion; fecal excretion (<1%)
Category A/B
Category C
NRTI
Antiretroviral, NRTI