Comparative Pharmacology
Head-to-head clinical analysis: EMTRIVA versus SYMTUZA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMTRIVA versus SYMTUZA.
EMTRIVA vs SYMTUZA
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.
SYMTUZA is a fixed-dose combination of darunavir (a HIV-1 protease inhibitor), cobicistat (a CYP3A inhibitor), emtricitabine (a nucleoside reverse transcriptase inhibitor), and tenofovir alafenamide (a nucleotide reverse transcriptase inhibitor). Darunavir inhibits HIV-1 protease, preventing cleavage of viral polyproteins and resulting in immature, non-infectious virus. Emtricitabine and tenofovir alafenamide inhibit HIV reverse transcriptase by competing with natural substrates and causing DNA chain termination. Cobicistat inhibits CYP3A, boosting darunavir exposure.
Emtricitabine 200 mg orally once daily.
One tablet (darunavir 800 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir alafenamide 10 mg) orally once daily with food.
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)
Darunavir: 15 hours (when boosted with cobicistat). Cobicistat: 3-4 hours. Emtricitabine: 10 hours. Tenofovir alafenamide: 0.5 hours (active metabolite tenofovir diphosphate intracellular half-life >60 hours).
Renal excretion of unchanged drug (~86%) by glomerular filtration and active tubular secretion; fecal excretion (<1%)
Darunavir: ~80% feces (mostly metabolites), ~14% urine (unchanged 1.5%). Cobicistat: ~86% feces, ~8% urine. Emtricitabine: ~86% urine (unchanged), ~14% feces. Tenofovir alafenamide: ~31% urine, ~47% feces (as tenofovir).
Category C
Category C
Antiretroviral, NRTI
Antiretroviral