HIV: Gene therapy breakthrough patients on medication
6 March 2014 Last updated at 22:55 GMT
For the first time gene therapy has been used to boost the immune system of people with HIV.
Scientists in the US have modified the genes of HIV patients which might mean that in future they would not need to take daily medication.
It is estimated there are more than 35 million people infected with HIV around the world but the use of anti-retroviral drugs has greatly reduced the number of deaths.
Despite that more than 1.5m people die of complications with AIDS every year.
Fergus Walsh reports.