{"id":24021,"date":"2013-12-01T11:45:11","date_gmt":"2013-12-01T11:45:11","guid":{"rendered":"http:\/\/i-base.info\/htb\/?p=24021"},"modified":"2016-11-04T15:42:17","modified_gmt":"2016-11-04T15:42:17","slug":"dsmb-stops-boosted-atazanavir-monotherapy-study-due-to-virological-failure","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/24021","title":{"rendered":"DSMB stops boosted atazanavir monotherapy study due to virological failure"},"content":{"rendered":"

<\/strong>\"EACS<\/strong>Simon Collins, HIV i-Base<\/p>\n

Interim results from a study that switched virally suppressed patients to boosted atazanavir monotherapy, showed a significantly higher rate of failure compared to standard of care triple therapy.<\/strong><\/p>\n

This was a randomised, open label, non-inferiority study in 103 patients (84% males, 13% HCV-infected, median (IQR) age of 42 (36-48) years).<\/p>\n

Enrolment criteria included viral suppression to <50 copies\/mL for greater than 6 months on a combination that included atazanavir\/ritonavir (300\/100 mg) plus two NRTIs. Participants were randomised to switch to atazanavir\/rintonavir monotherapy or continue with triple therapy.<\/p>\n

In the 48-week interim analysis (ITT analysis), viral suppression was maintained by 73% (37\/51 patients) in the monotherapy arm compared to 85% (44\/52) in the triple-therapy arm (difference: -12.1%, 95% CI: -27.8 to 3.6).<\/p>\n

This was sufficient for the Data and Safety Monitoring Board (DSMB) to recommended to stopping the study. Confirmed virological failure occurred in \u202811 vs 2 patients in the monotherapy vs triple-therapy groups and although this was reported as significantly more common in people with HCV coinfection (56% vs 17%; p=0.024), this was in very small numbers of patients.<\/p>\n

Viral load was resuppressed in all patients with virological rebound by reintroducing previous NRTIs. Although drug resistant mutations were not detected, median HIV viral load was only 197 (IQR 134-510) copies\/mL at the time of testing.<\/p>\n

Although drug-related side effects were more common in the triple therapy group (n=0 vs 6, p=0.027), it is notable that these were mostly associated with atazanavir (5\/6) rather than the NRTIs.<\/p>\n

Comment<\/h3>\n

An earlier study already reported high rates of virological failure when atazanavir is used as boosted monotherapy.<\/strong> [2]<\/p>\n

It therefore is unclear why Bristol-Myers Squibb supported this study other than from a marketing-driven interest.<\/strong><\/p>\n

References:<\/p>\n

    \n
  1. Castagna A et al. 48 weeks outcomes of atazanavir\/ritonavir monotherapy as maintenance strategy in HIV-1 treated subjects with viral suppression: interim analysis results of the MODAt Study. 14th European AIDS Conference (EACS), 16-19 October 2013, Brussels. Abstract PS 4\/2.
    \nhttp:\/\/www.abstractserver.com\/eacsabstractarchive\/absabstract.php?abid=4861<\/a><\/li>\n
  2. Karlstrom et al. Early virologic rebound in a pilot trial of ritonavir-boosted atazanavir as maintenance monotherapy. J Acquir Immune Defic Syndr. 2007 Apr 1;44(4):417-22.
    \n    http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/17159658<\/a><\/li>\n<\/ol>\n

    Full text on Medscape (one-time free registration required).
    \n    http:\/\/www.medscape.com\/viewarticle\/554859<\/a><\/p>\n

    \u00a0<\/strong><\/div>\n","protected":false},"excerpt":{"rendered":"

    Simon Collins, HIV i-Base Interim results from a study that switched virally suppressed patients to boosted atazanavir monotherapy, showed a significantly higher rate of failure compared to standard of care triple therapy. This was a randomised, open label, non-inferiority study …<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,3],"tags":[181],"class_list":["post-24021","post","type-post","status-publish","format-standard","hentry","category-conference-reports","category-antiretrovirals","tag-eacs-14-brussels-2013"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/24021","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\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=24021"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/24021\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=24021"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=24021"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=24021"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}