Protease Inhibitor Pharmacokinetics

Published on: November 12, 2001

Patrick Smith, Pharm.D.

Clinical Assistant Professor, Department of Pharmacy Practice
School of Pharmacy and Pharmaceutical Sciences
University at Buffalo
E-mail: pfsmith@buffalo.edu

Drug	Typical Adult Dose	Bioavail-ability (%)	Protein Binding (%)	Metabolism	In Vitro Susceptibility (IC50 range)	T1/2 (h)	Vd (L/kg)
Amprenavir	1200 mg bid	86	90	CYP3A4,2D6,2C9	0.012-0.08 μM	7.1-10.6	430 L
Indinavir	800 mg q8h	60	60	CYP3A4	0.025-0.1 μMa	1.5	1.2
Nelfinavir	750 mg tid	20-80	98	CYP3A4	0.009-0.06 μM	2.6	2-7
Ritonavir	600 mg bid	60	98-99	CYP3A, CYP2D6	0.0038-0.154 μM	3-5	0.41
Saquinavir (Fortovase)	1200 mg tid	12	98	CYP3A4	0.001-0.03 μM	3	10
Saquinavir (Invirase)	600 mg tid	4	98	CYP3A4	N/A	3	10

Abbreviations: bid, twice daily; tid, thrice daily; q8h, every 8 hours; q12h, every 12 hours
^a Range given is for IC90 (concentration necessary to inhibit 90% of viral replication)