The first person cured of HIV, Timothy Ray Brown, has died from cancer.
Brown, who was also known as "the Berlin patient", was given a bone marrow transplant from a donor who was naturally resistant to HIV, the BBC reported.
It meant he no longer needed anti-viral drugs and he remained free of the virus, which can lead to AIDS, for the rest of his life.
The International AIDS Society said Brown gave the world hope that a HIV cure was possible.
Brown, 54, who was born in the US, was diagnosed with HIV while he lived in Berlin in 1995. Then in 2007 he developed a type of blood cancer called acute myeloid leukaemia.
His treatment involved destroying his bone marrow, which was producing the cancerous cells, and then having a bone marrow transplant.
"It is with great sadness that I announce that Timothy passed away... surrounded by myself and friends, after a five-month battle with leukaemia," his partner Tim Hoeffgen posted on Facebook.
He added: "Tim committed his life's work to telling his story about his HIV cure and became an ambassador of hope."