In the UK, guidelines suggest that antiretroviral treatment (ART) should be started when the patient’s CD4 count (a measure of how well the immune system is doing) falls to 350; in the US and most of Europe, guidelines suggest starting sooner, at a CD4 of 500. This is because the data about the benefits of starting ART sooner (at a higher CD4 count) is mixed – some studies show a benefit, others don’t.

In order to clarify this, a large clinical trial called START was set up in 2012. Results were not expected until 2017. However, in May 2015, the organisers of the trial annouced some results, and changes to the trial. The results are very clear: there are significant benefits in starting ART early, with a high CD4 count, rather than waiting until the CD4 count falls to 350. 

UK clinical guidelines will be re-written to reflect these results; however, this is likely to take some years, because the clinicians writing the guidelines want to see the full results of the START trial, which will not be available until 2017. However, everybody considering starting ART should be made aware of these trial results, and should be offered the opportunity to start ART, no matter what their CD4 count is.

The full aricle can be read here; a supplementary Q & A is given here.