People on ART much less likely to infect partners

“Among the 877 couples in the delayed ART group, 27 HIV transmissions occurred. This was in contrast to only one (1) transmission that occurred in the immediate ART group. This difference was highly statistically significant. The viruses transmitted in these 28 cases were confirmed to be linked by genetic analysis, confirming that the source of the new infection was the previously HIV-infected partner.

This is a very important study that has just been terminated:
http://www.hptn.org/web%20documents/PressReleases/HPTN052PressReleaseFINAL5_12_118am.pdf

This is the key finding:

“Among the 877 couples in the delayed ART group, 27 HIV transmissions occurred. This was in contrast to only one (1) transmission that occurred in the immediate ART group. This difference was highly statistically significant. The viruses transmitted in these 28 cases were confirmed to be linked by genetic analysis, confirming that the source of the new infection was the previously HIV-infected partner.”

Please note: people on this trial were strongly encouraged to practice safer sex. This intervention, strictly speaking, was ART plus condom promotion plus STI treatment  versus condom promotion plus STI treatment.

This has important implications for when ART is initiated. Over the last few years data has been collected which shows:

  1. Early ART is unlikely to be harmful. (Several observational studies show this.)
  2. Early ART might be beneficial. (Several observational studies show this, but the data is not clearcut.)
  3. HIV-positive people on ART are less infectious to their partners than HIV-positive people not on ART. If I understand this study correctly, we can say that giving ART to HIV-positive people is the most effective known way to reduce transmission risk to their partners. Coupled with circumcision (for heterosexual HIV-negative men) and condom promotion, we can make real headway against HIV incidence.
  4. The greater the proportion of HIV-positive people in a community with high TB prevalence on ART, the lower TB transmission. (Observational data from a Cape Town township shows this.)

Two randomised controlled studies are ongoing which should help us answer once and for all whether ART should be offered to all people with HIV:

  1. Strategic Timing of Antiretroviral Treatment (START)
    http://clinicaltrials.gov/ct2/show/NCT00867048 (due to complete in 2015)
    There is one START site in South Africa – the Desmond Tutu HIV Centre at UCT in Cape Town. If you live in Cape Town and you have HIV-positive with a CD4 count > 500 cells/mm3, please consider enrolling in this trial.
  2. Early Antiretroviral Treatment and/or Early Isoniazid Prophylaxis Against Tuberculosis in HIV-infected Adults (ANRS 12136 TEMPRANO) (which is being run in Côte d’Ivoire)
    http://clinicaltrials.gov/ct2/show/NCT00495651 (due to complete in 2013)

Guidelines have already been changed in several countries to recommend earlier treatment.

There will be significant cost implications of offering ART to all people with HIV, but reduced infections may help offset the long-term costs. The following study does not answer the cost questions associated with early treatment, but it is useful as a starting point:
http://www.section27.org.za/wp-content/uploads/2010/11/NACM_Presentation.pdf

This also has implications for the new HIV/TB National Strategic Plan for South Africa. While the guidelines for the early years will probably remain unchanged, by 2013/2014 it is possible that early ART will become standard; in which case the NSP must plan for this.

In the meanwhile, we must urge the DOH to treat everyone at a CD4 threshold of 350 cells/mm3, at minimum.

Perhaps we should even begin test-and-treat pilots in several districts.

Nathan Geffen

(Declaration of possible conflict of interests: I am on the Community Advisory Board for START.)

 

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