title: Pharmacokinetics and safety of saquinavir/ritonavir and omeprazole in HIV-infected subjects.
abstract: We investigated the pharmacokinetics and safety of saquinavir/ritonavir when administered with omeprazole simultaneously and 2 h apart to human immunodeficiency virus (HIV) subjects. Saquinavir/ritonavir 12-h pharmacokinetics was assessed with and without omeprazole 40 mg. Subjects were randomized to group A (saquinavir/ritonavir and omeprazole simultaneously/2 h apart) or group B (saquinavir/ritonavir and omeprazole 2 h apart/simultaneously). Saquinavir/ritonavir pharmacokinetics was assessed on days 1, 8, and 22. Within-subject changes were evaluated by geometric mean ratios and 90% confidence interval (CI). Twelve subjects completed the study. GM (90% CI) for saquinavir area under the curve (AUC)(0-12) (ng h/ml), trough concentration (C(trough)) (ng/ml), and maximum concentration (C(max)) (ng/ml) were 14,698 (13,242-20,636), 433 (368-758), 2,513 (2,243-3,329) without omeprazole; 22,646 (18,536-131,861), 750 (619-1,280), 3,890 (3,223-5,133) with omeprazole simultaneously; and 24,549 (20,884-38,894), 851 (720-1,782), 4,141 (3,554-5,992) with omeprazole 2 h earlier. Simultaneous administration of omeprazole significantly increased saquinavir AUC(0-12), C(trough), and C(max) by 54, 73, and 55%, whereas staggered administration by 67, 97, and 65%. No grade 3/4 toxicity or lab abnormalities were observed. In the presence of omeprazole, saquinavir plasma exposure is significantly increased in HIV-infected subjects whether administered simultaneously or 2 h apart.
authors: St Stephen's Centre, Chelsea and Westminster NHS Foundation Trust, London, UK.
authors: K
authors: K
authors: Singh
authors: L
authors: L
authors: Dickinson
authors: A
authors: A
authors: Chaikan
authors: D
authors: D
authors: Back
authors: C
authors: C
authors: Fletcher
authors: A
authors: A
authors: Pozniak
authors: G
authors: G
authors: Moyle
authors: M
authors: M
authors: Nelson
authors: B
authors: B
authors: Gazzard
authors: D
authors: D
authors: Herath
authors: M
authors: M
authors: Boffito
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004347:Drug Interactions / Q000502:physiology; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000188:drug therapy; D015497:HIV-1 / Q000187:drug effects; D006261:Headache / Q000097:blood / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D009853:Omeprazole / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*; D019438:Ritonavir / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*; D019258:Saquinavir / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D009853:Omeprazole; D019258:Saquinavir; D019438:Ritonavir