A study published in the April 2007 issue of the journal AIDS found treatment interruptions to be safe in people who began anti-HIV drug treatment for the first time when their CD4 counts were above 350. This finding is at odds with other studies of treatment interruptions -- most notably the SMART study, but also PART, DART and TRIVICAN -- which all found treatment interruptions to be risky. The difference may be due to the groups of people being studied.

Researchers looked at people from the ATHENA cohort, which includes all HIV-infected people getting care in the Netherlands. To be eligible people had to be on stable antiretroviral treatment for at least one year, have undetectable HIV at the start of the study and, most notably, had to have started taking HIV drugs for the first time with CD4 counts above 350. Other research has shown that treatment interruptions are riskier for people whose CD4 levels have been low at some point. A person's lowest ever CD4 count is called a nadir CD4.

In this study, 71 people were given the choice whether to stop or continue taking their anti-HIV drug regimens. A total of 46 people chose to stop, while 26 decided to continue. After 48 weeks, 5 (11%) of people in the group who interrupted treatment restarted, none because of illness. After 48 weeks, people who stopped their treatment saw HIV levels rise to pre-treatment levels, but their average CD4 count remained 85 cells above pre-treatment levels. Nobody had CD4 counts dip below 300.

Researchers also looked at measures of quality of life, and found no significant differences between the groups.
Due to SMART and other studies, the trend has been decidedly negative for treatment interruptions of late. These results seem to suggest that treatment interruptions might be safe for those who started anti-HIV therapy with high CD4 counts. Importantly, it found no quality of life benefit or cost to interrupting treatment.

It is important to note that this was a small study, and almost 86% of the people studied were men. It was also not a randomized trial, as participants were able to choose whether to stay on or interrupt treatment. The results of non-randomized trials are considered less reliable than randomized ones. This study suggests the need for more research on treatment interruption in people whose immune systems have never been significantly damaged by HIV.