{"id":9906,"date":"2004-04-03T08:49:16","date_gmt":"2004-04-03T08:49:16","guid":{"rendered":"http:\/\/i-base.info\/htb\/?p=9906"},"modified":"2014-05-22T18:17:46","modified_gmt":"2014-05-22T18:17:46","slug":"ribavirin-rbv-does-not-alter-intracellular-levels-of-azt-3tc-or-d4t","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/9906","title":{"rendered":"Ribavirin (RBV) does not alter intracellular levels of AZT, 3TC or d4T"},"content":{"rendered":"<p><strong>Simon Collins, HIV i-Base<\/strong><\/p>\n<p><strong>In a late-breaker oral presentation, Gries and colleagues presented results from a PK sub-study of the APRICOT trial. This study randomised more than 800 patients coinfected with HIV and HCV to either standard interferon-alfa + ribavirin, pegylated interferon (Pegasys) + placebo or Pegasys + ribavirin. Results from the full APRICOT study are reported in detail later in this issue of HTB.<\/strong><\/p>\n<p>The PK study only included patients receiving pegylated interferon +\/- ribavirin 800mg\/day or placebo. Stable background HAART included either AZT+3TC or d4T+3TC for more than six weeks prior to the study.<\/p>\n<p>Serial blood samples were collected at 0, 2, 4, 6, 8 and 12 hours at baseline and after 8-12 weeks of therapy. Plasma concentrations of RBV, d4T, AZT and 3TC were determined by LC\/MS\/MS and triphosphate metabolites in PBMCs by template primer extension assays.<\/p>\n<p>No significant differences were found in either the mean plasma or intracellular AUC levels between baseline and week 8-12 in the 48\/55 patients who completed the sub-study. The study concluded that coadministration of ribavirin does not alter the intracellular phosphorylation or the plasma pharmacokinetics of AZT, d4T or 3TC in coinfection patients after 8-12 weeks.<\/p>\n<h3>Comment<\/h3>\n<p><strong>For historical reasons, the main concern at the time when this sub-study in APRICOT was designed was the inhibition of the phosphorylation of pyrimidine-analogues by ribavirin.<\/strong><\/p>\n<p><strong>However, today the toxicity of ddI which may be increased by a promotion of phosporylation by ribavirin is of a much greater relevance. Unfortunately data on this interaction are not provided by this study.<\/strong><\/p>\n<p>Reference:<\/p>\n<p>Gries J-M, Torriani FJ, Rodriguez-Torres M et al. Effect of ribavirin on intracellular and plasma pharmacokinetics of nucleoside reverse transcriptase inhibitors in patients with HCV\/HIV co-infection: final results of a randomised clinical study. 11th CROI 2004, Abstract 135LB.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Simon Collins, HIV i-Base In a late-breaker oral presentation, Gries and colleagues presented results from a PK sub-study of the APRICOT trial. This study randomised more than 800 patients coinfected with HIV and HCV to either standard interferon-alfa + ribavirin, &hellip;<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,34,24],"tags":[58],"class_list":["post-9906","post","type-post","status-publish","format-standard","hentry","category-conference-reports","category-pk-and-drug-interactions","category-hepatitis-coinfection","tag-croi-2004"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/9906","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\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=9906"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/9906\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=9906"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=9906"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=9906"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}