{"id":3221,"date":"2006-06-11T06:52:44","date_gmt":"2006-06-11T05:52:44","guid":{"rendered":"http:\/\/moomango.co.uk\/htb\/?p=3221"},"modified":"2013-12-06T18:07:10","modified_gmt":"2013-12-06T18:07:10","slug":"using-enzyme-inducers-to-reduce-the-half-life-of-nevirapine","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/3221","title":{"rendered":"Using enzyme inducers to reduce the half-life of nevirapine"},"content":{"rendered":"<p><strong>Polly Clayden, HIV i-Base<\/strong><\/p>\n<p><strong>Several studies have reported the development of resistance to nevirapine even after taking a single dose of the drug, which is commonly used in the resource-limited setting for the prevention of mother to child transmission. This is likely due to the long half-life of nevirapine that results in the drug being found in blood for many days after taking the one dose.<\/strong><\/p>\n<p>A poster from Rafaella L\u0092homme and coworkers from the Radboud University Nijmegen Medical Centre presented findings from a study exploring the novel strategy of using enzyme inducers to reduce nevirapine half-life and thereby reduce the risk of developing resistance.<\/p>\n<p>This small study evaluated the use of several different strategies including using carbamazepine, phenobarbital, phenytoin, St. John\u0092s Wort tea, retinyl palmitate and beta-carotene, and cholecalciferol.<\/p>\n<p>This was a phase-I single-centre, open-label, two period, nine-group, PK study. A single 200 mg dose of nevirapine was administered to 36 HIV negative non-pregnant women in both period 1 and 2, blood samples were taken twice weekly for 21 days. In period 2 additional interventions (single dose carbamazepine, phenobarbital or phenytoin; phenytoin for 3 or 7 days; St Johns Wort, vitamin A or cholecalciferol for 14 days) were administered to all participants except for the control group. The primary end point was the ratio of nevirapine half-life in period 2 to nevirapine half-life in period 1.<\/p>\n<p>Three of the interventions resulted in the half-life of nevirapine being significantly reduced. These included a single 400mg dose of carbamazepine (p=0.002), once a day 184mg phenytoin for three days (p=0.001) and once a day 184mg phenytoin for seven days (p=0.002). The half-life of nevirapine was reduced by 35.3%, 38.2% and 35.9% respectively. This resulted in a 4.5 \u0096 8.8 day reduction in time to when nevirapine could not be detected in blood. The other five interventions had no effect on the nevirapine half-life.<\/p>\n<p>These interventions now need to be studied in the real world setting to determine if this will lead to a decreased risk of developing resistance to nevirapine among pregnant women taking single dose nevirapine to prevent HIV transmission to their newborns.<\/p>\n<p class=\"ref\">Reference:<\/p>\n<p class=\"ref\">L\u0092homme R, Dijkema T, A. van der Ven A et al. Enzyme inducers reduce nevirapine half-life. 7th International Workshop on Clinical Pharmacology of HIV Therapy, 20-22 April 2006, Lisbon. Abstract 5.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Polly Clayden, HIV i-Base Several studies have reported the development of resistance to nevirapine even after taking a single dose of the drug, which is commonly used in the resource-limited setting for the prevention of mother to child transmission. This &hellip;<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[143],"class_list":["post-3221","post","type-post","status-publish","format-standard","hentry","category-conference-reports","tag-pk-workshop-2006"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/3221","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=3221"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/3221\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=3221"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=3221"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=3221"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}