Comparative Pharmacology
Head-to-head clinical analysis: ATAZANAVIR SULFATE versus FOSAMPRENAVIR CALCIUM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ATAZANAVIR SULFATE versus FOSAMPRENAVIR CALCIUM.
ATAZANAVIR SULFATE vs FOSAMPRENAVIR CALCIUM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Atazanavir is an azapeptide HIV-1 protease inhibitor. It selectively inhibits the virus-specific processing of viral Gag and Gag-Pol polyproteins in HIV-1 infected cells, preventing formation of mature virions.
Fosamprenavir is a prodrug of amprenavir, an HIV-1 protease inhibitor. It binds to the active site of HIV-1 protease, preventing cleavage of viral Gag-Pol polyproteins, resulting in immature, non-infectious viral particles.
300 mg orally once daily with ritonavir 100 mg orally once daily, or 400 mg orally once daily without ritonavir (when used alone).
1400 mg orally twice daily or 1400 mg once daily plus ritonavir 100 mg or 200 mg once daily plus ritonavir 100 mg. Alternatively, fosamprenavir 700 mg plus ritonavir 100 mg twice daily.
None Documented
None Documented
Terminal elimination half-life: ~6.5 to 7 hours; supports once-daily dosing.
Terminal elimination half-life is approximately 7.7 hours; supports twice-daily dosing.
Biliary/fecal: ~79% as unchanged drug; renal: ~13% (including <1% unchanged).
Primarily hepatic metabolism via CYP3A4, with 14% renal excretion of unchanged drug; 68% fecal, 1% urinary as unchanged drug.
Category C
Category A/B
Protease Inhibitor
Protease Inhibitor