Studies have shown that the efficacy of antiretroviral treatment dramatically reduces the risk of HIV transmission following - a concept known as "treatment and prevention" - PrEP and reduced the risk of infection over 90% is taken consistently.
HIV-negative partners initial PrEP study in serodiscordant heterosexual couples Dr Baeteninitially presented to the conference the International AIDS Society conference in 2011They were randomly assigned in Kenya and Uganda to receive tenofovir / emtricitabine (componentsTruvada), Tenofovir without co-formulation or placebo. (By the time this occurred the guidelines of the World Health Organization and the country recommended ART initiation based on CD4 cell count and not for everyone diagnosed with HIV).
The tracking withPartner Study demonstration and PrEP, In order to show whether an integrated combination of PrEP for negative partners more ART for positive partners could further reduce the risk of HIV transmission. By the time this study was initiated in November 2012 there was ample evidence that both PrEP and treatment as prevention (TASP - Acronym for the Prevention Treatment - Treatment as prevention in free translation) They were effective, so that all participants received both interventions on an open source basis (non-random).
The demonstration project was conducted in four centers in Kenya and Uganda which hosted the initial partners of the study randomized to PrEP, but were inscribed a new cohort of 1013 serodiscordant heterosexual couples in which neither partner had ever taken antiretrovirals.
The average age of participants was 30 years. In two-thirds of the couples the woman was HIV positive partner. positive partners had an average score of CD4 cells was 436 cells / mm3 and the average viral load in more than 37.000 copies / ml. Most (65%) said they had had sexual relations unprotected form last month.
Upon enrollment, it was offered to HIV positive partner to combination antiretroviral therapy in accordance with national guidelines - less than 350 cells / mm3 until mid-2013 and then later, the universal treatment - while the HIV negative partner was offered dailyTruvada. PrEP was continued while the positive partner lingered at the start of treatment in the first six months after initiation of antiretroviral therapy, allowing the passage of time so that the viral load undetectable stay; PrEP was extended if the positive partner had treatment interruptions or known poor adherence.
The demonstration project measured the couples selected based on an algorithm of risk scores that were 1 10 to depending predictors of risk of HIV infection, including young couples in cohabitation arrangements instead of marriage, recent unprotected sex, male partners uncircumcised partners and positive with a high viral load; couples with a score of 5 or more were eligible for the study.
In 2015 Conference on Retroviruses and Opportunistic Infections (end)Dr. Baeten reported interim resultsShowing that two HIV-negative partners seroconverted initially. Instead of a placebo arm, researchers have used both incidence rate in the original placebo arm random Prep study partners to estimate that 40 new infections have been expected in the absence of ART and PrEP - a reduction of risk 96%.
This week Dr Baeten showed results updated with final data through June 2016, reflecting approximately 1700 person-year follow-up.
By this time, 91% of the positive partner had started ART and almost all had achieved viral suppression (<400 copies / ml) - (Editor's note: It is apparent disrespect to the Treaty of Helsinki which provides the research subject the best existing treatment, not the best available Give viral load measurement systems accurately pair a minimum of 20 copies / ml Most (.. 97%) negative partners who have been offered PrEP accepted it. Couples in solitary ART (...) were in 39% of follow-up, solitary PrEP in 20% overlap ART and PrEP to 33% nor HAART or PrEP to 7%.
At the end of follow-up of four new HIV infections occurred, compared to 83 expected without antiretroviral therapy or PrEP, for a relative risk reduction of 95%. Protection was similar, regardless of gender, age or pre-treatment adherence viral.A load both PrEP and ART was good during the demonstration project. Other partners of HIV-negative patients who started PrEP were randomly selected for testing serum concentration of the drug, 82% of the blood samples showed detectable levels of tenofovir
However, none of the newly infected individuals actually make use of HAART and PrEP consistently - and in fact they were in couples who did not use these recursosá
A woman had broken with its positive partner and stopped PrEP, while a second woman had a partner who has not wanted to start treatment and she stopped PrEP; nor the woman had a detectable serum concentrations of tenofovir in your blood sample at the time of infection. A third woman was a sex worker making inconsistent use of PrEP. The only man who had the infection had decreased the use of PrEP and had multiple sexual partners.
"In this open design to demonstrate the integrated delivery of ARV treatment and PrEP for HIV prevention among discordant couples, We observe the virtual elimination of HIV incident, "The researchers concluded.
"Interventions such as this could have a substantial effect on the HIV epidemic," said Dr Baeten at the press conference of the AIDS Conference in 2016:
"As far as PrEP ART are extremely important interventions
could virtually eliminate HIV transmission(Sic). "
There is more to be seen on this linkand I advise reading
Published in aidsmap in: 21 July 2016
Translated Claudio Souza in August 04 2016 from the original:PrEP can further reduce the risk of HIV infection after a partner starts treatment. Reviewed by Mara Macedo