{"id":16551,"date":"2012-06-01T10:11:01","date_gmt":"2012-06-01T10:11:01","guid":{"rendered":"http:\/\/i-base.info\/htb\/?p=16551"},"modified":"2012-07-21T05:41:53","modified_gmt":"2012-07-21T05:41:53","slug":"pharmacokinetics-of-atazanavirritonavir-plus-raltegravir","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/16551","title":{"rendered":"Pharmacokinetics of atazanavir\/ritonavir plus raltegravir"},"content":{"rendered":"<p><strong><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-full wp-image-16567\" title=\"13th PK logo\" src=\"https:\/\/i-base.info\/htb\/files\/2012\/05\/13th-PK-logo.png\" alt=\"\" width=\"160\" height=\"81\" \/>www.drug-interactions.org<\/strong><\/p>\n<p><strong>Current dosing for raltegravir is 400 mg twice daily, but atazanavir increases raltegravir exposure by 40-72% probably through UGT1A1 inhibition.<\/strong><\/p>\n<p>This pharmacological pilot phase II study investigated the pharmacokinetics of raltegravir 400 mg once daily in 6 HIV positive men receiving 2 NRTIs plus atazanavir\/r. Three patients were taking tenfovir\/FTC.<\/p>\n<p>Half-dose raltegravir exposure, when combined with atazanavir\/r, seemed to be adequate in the majority of patients, with only one trough value below the IC95 (15 ng\/ml). Raltegravir AUC, Cmax and Ctrough (median, IQR) were 14497 ng.h\/ml (13845-28325), 3984 ng\/ml (3863-6703) and 40 ng\/mL (22-51), respectively. Median (IQR) atazanavir AUC, Cmax, and Ctrough were 26414 ng.h\/mL (23037-33109), 2284 ng\/mL (1706-2666) and 526 ng\/mL (397-604), respectively. Median (IQR) ritonavir AUC, Cmax and Ctrough were 9147 ng.h\/mL (8052-12860), 1107 ng\/mL (983-1244), 99 ng\/mL (61-183), respectively.<\/p>\n<p>The AUC of raltegravir 400 mg once daily in this study was similar to the AUC of the 800 mg once daily dosage in the QDMARK study (14895 ng.h\/ml), and resulted in two-fold higher than the reported AUC values with standard 400 mg twice-daily dosage (6340 to6910 ng.h\/ml). However, QDMARK reported that raltegravir 400 mg once-daily with atazanavir\/r resulted in poorer rates of viral suppression.<\/p>\n<p>Atazanavir concentrations were comparable to historical data and Ctroughs were above the target level (150 ng\/mL) in all patients.<\/p>\n<p>Reference:<\/p>\n<p>Calcagno A et al.Pharmacokinetics of raltegravir 400 mg once-daily in combination with atazanavir\/ritonavir plus two NRTIs. 13th PK Workshop, 16-18 April 2012, Barcelona. Poster abstract P_05.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>www.drug-interactions.org Current dosing for raltegravir is 400 mg twice daily, but atazanavir increases raltegravir exposure by 40-72% probably through UGT1A1 inhibition. This pharmacological pilot phase II study investigated the pharmacokinetics of raltegravir 400 mg once daily in 6 HIV positive &hellip;<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,3,34],"tags":[136],"class_list":["post-16551","post","type-post","status-publish","format-standard","hentry","category-conference-reports","category-antiretrovirals","category-pk-and-drug-interactions","tag-pk-workshop-13th-2012"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/16551","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=16551"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/16551\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=16551"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=16551"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=16551"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}