20 achievements from 20 years: The START trial shows it’s best to start HIV treatment as soon as possible
While many of our studies have changed policy and practice, few have had as fast an impact as the START study. At the same conference the START trial results were first presented, the World Health Organisation announced it would update its recommendations in the light of the START results. These were published in September, just two months later.
Other organisations were also swift to respond to the START trial results. National guideline developers from many countries, including the UK and USA, updated their guidance within a few months of the results being made public.
START was testing when people living with HIV should start antiretroviral therapy. Antiretroviral therapy is very effective at treating HIV, but it does have side effects and is costly. Until the START results were released, it was not clear whether it is better for a person with HIV whose immune system is still intact to wait until their immune system had been weakened by the disease before starting treatment for life, or to start it as soon as possible.
START established that starting antiretroviral therapy straight away benefits HIV-infected individuals regardless of the state of their immune system. START found that starting treatment straight away more than halved the rate of serious illnesses and deaths.
More than 4,600 HIV positive people from 35 countries took part in START. Everyone joining the trial had a CD4 count above 500 (a mark of how well their immune system was doing). Half of people in the trial were randomised to start antiretroviral therapy straight away, while the other half were randomised to wait until their CD4 count had dropped below 350.
The START team are continuing to follow-up participants to look at the longer-term effects of starting ART immediately or waiting until the CD4 count falls below 350. As START is such a large study, the data collected will also provide insight into other important questions about HIV and how to treat it. The START trial was carried out by the International Network for Strategic Initiatives in Global HIV Trials (INSIGHT).