Results from the BREATHER trial, presented yesterday at the CROI conference, indicate that, depending on the combination of drugs used, it may be safe in the short-term for some young people living with HIV to have a short break from HIV medicines at the weekend. But the researchers warn that more evidence about the long-term safety of this strategy is needed before this approach is used outside of a clinical trial.
HIV drugs can keep the virus under control if there are sufficient levels of the drugs in a person's blood stream. For most currently available drugs this means taking the drugs every day. This can be challenging for young people living with HIV. The HIV drug Efavirenz stays at active levels in the blood for longer than other commonly used HIV drugs. The BREATHER trial was set up to test whether young people could safely have a break from their HIV drugs at the weekend, if they took a regimen containing Efavirenz every weekday.
199 HIV-infected young people, aged between 8-24 years, from around the world, took part in BREATHER. They were all already on HIV treatment, and their virus was under very well controlled, i.e. undetectable, at the start of the trial. They were all on a combination of HIV drugs that included the drug Efavirenz. Half the young people were randomised to continue taking their drugs every day. The other half were randomised to 'short cycle therapy', where they took their drugs five days a week, and had two days a week off from HIV drugs.
After one year, young people who took their drugs consistently for the same five days each week were just as likely to have their virus under control as those who took their drugs every day. Very few people in either group had a detectable increase in their viral load (six in the short cycle therapy group, and seven in the continuous therapy group). Those in the short cycle therapy group whose virus increased were put back on continuous treatment (either on the same drugs or with different ones), and five out of six of them got their virus back under control. There was no significant difference in side-effects between the groups, and young people in the short cycle therapy group were not more likely to develop drug resistance.
As part of the trial some of the young people were interviewed about their views and experiences of taking HIV drugs and of short cycle therapy. To begin with, for some of them moving from daily treatment to having weekends off was confusing and worrying. However, once they had adapted to having weekends off, young people enjoyed the freedom it gave them, and preferred it to taking treatment every day.
While these results are encouraging, the researchers warn that there is not yet enough evidence to recommend short-cycle therapy. It is also important to remember that these results only apply to people taking the drug Efavirenz. BREATHER was a relatively small trial, and had only a short follow-up. We do not know whether short cycle therapy will be safe and effective in the longer-term. The BREATHER trial has been extended for another two years, to help answer this question. In the meantime, other people living with HIV should continue to take their drugs daily.
BREATHER was carried out in 11 countries from Europe, Africa, Asia, North America and South America. It was funded in the UK and Ireland by the NIHR Technology Assessment Programme, and in the rest of the world by the PENTA Foundation.