{"id":29568,"date":"2016-02-01T12:08:31","date_gmt":"2016-02-01T12:08:31","guid":{"rendered":"http:\/\/i-base.info\/htb\/?p=29568"},"modified":"2017-01-06T20:26:36","modified_gmt":"2017-01-06T20:26:36","slug":"two-cases-of-hiv-transmission-on-tenofovir-df-monotherapy","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/29568","title":{"rendered":"Two cases of HIV transmission on tenofovir DF monotherapy"},"content":{"rendered":"

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

Case studies were recently published of two men who became HIV positive even though they were using daily tenofovir DF to treat hepatitis B (HBV).<\/strong><\/p>\n

The cases are important because this provides evidence that in the context of good adherence that both tenofovir DF and FTC might be needed to reach close to 100% protection for men.<\/p>\n

Both cases were in gay men with good adherence. This was demonstrated by undetectable HBV viral load without blips for >3 years supported by pharmacy records, and by therapeutic drug levels tenofovir at the time of HIV diagnosis.<\/p>\n

One case was diagnosed in acute HIV infection following 4 day of flu-like symptoms after an exposure risk – and 10 days after a negative antibody test. Viral load was <50 copies\/mL.<\/p>\n

The second case was identified after hospitalisation for severe seroconversion illness, diagnosed with a viral load of 160,000 c\/mL.<\/p>\n

Both men had immediate escalation to full ART – within approximately three weeks after likely date of infection – but this did not prevent infection. Established infection was verified by HIV total DNA and integrated DNA in both cases.<\/p>\n

The results are also important because the WHO currently recommend tenofovir DF as a single drug option for PrEP based on non-significant differences compared to tenofovir DF\/FTC in the (heterosexual) PARTNERS PrEP study.<\/p>\n

Comment<\/h3>\n

While these two cases show proof of principle that infection is possible in the presence of likely good adherence to tenofovir, the absence of a denominator makes it impossible to quantify the level of risk.<\/strong><\/p>\n

The cases show the likely importance of dual therapy for PrEP which for many people is important for achieving close-to 100% protection. The results also support people at risk of HIV infection who are being treated for HBV switch to tenofovir\/FTC for their HBV treatment.<\/strong><\/p>\n

These cases were first presented at conferences in Glasgow in 2014 and at BHIVA in 2015.<\/strong> [2, 3]<\/p>\n

References:<\/p>\n

    \n
  1. Fox J et al. Tenofovir disoproxil fumarate fails to prevent HIV acquisition or the establishment of a viral reservoir: two case reports. Infect Dis Ther. Published online: 09 January 2016. DOI 10.1007\/s40121-015-0102-x.
    \nhttps:\/\/www.ncbi.nlm.nih.gov\/pubmed\/26746652<\/a><\/li>\n
  2. Davies O et al. Failure of daily tenofovir to prevent HIV transmission or the establishment of a significant viral reservoir despite contin-ued antiretroviral therapy. 14th International Congress on Drug Therapy in HIV Infection, 23-26 October 2014, Glasgow. Poster abstract P199.
    \n    http:\/\/www.jiasociety.org\/index.php\/jias\/article\/view\/19731<\/a><\/li>\n
  3. Fox J et al. Pre-exposure prophylaxis fails to prevent HIV-1 infection or the establishment of a significant viral reservoir. 21st BHIVA conference, 21-24 April 2015, Brighton. Poster abstract P10.
    \n    http:\/\/www.bhiva.org\/documents\/Conferences\/2015Brighton\/AbstractBook2015.pdf <\/a>(PDF)<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

    Simon Collins, HIV i-Base Case studies were recently published of two men who became HIV positive even though they were using daily tenofovir DF to treat hepatitis B (HBV). The cases are important because this provides evidence that in the …<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[],"class_list":["post-29568","post","type-post","status-publish","format-standard","hentry","category-transmission-and-prevention"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/29568","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=29568"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/29568\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=29568"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=29568"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=29568"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}