WASHINGTON - Signs of HIV have returned in two American men who appeared to have briefly eradicated the virus after bone marrow transplants for cancer, US doctors said Friday.
Experts said the discovery is a disappointment to efforts to find a cure for the human immunodeficiency virus behind AIDS, but offers important new clues in the hunt for the disease's elusive hiding places.
Only one person is believed to have been cured of HIV. American Timothy Brown, who suffered from leukemia, received a bone marrow transplant from a rare donor resistant to HIV and has shown no sign of the virus for six years.
"The return of detectible levels of HIV in our patients is disappointing, but scientifically significant," said Timothy Heinrich, a physician-researcher in the Division of Infectious Diseases at Brigham and Women's Hospital in Boston.
"Through this research we have discovered the HIV reservoir is deeper and more persistent than previously known," he said in a statement sent to AFP.
Heinrich first shared the news with fellow researchers at an international AIDS conference in Miami, Florida on Thursday.
Both HIV-positive men received bone marrow transplants as treatment for a kind of blood cancer known as Hodgkin's lymphoma, one in 2008 and the other in 2010.
About eight months after their operations, HIV was no longer detectable.
The patients stayed on antiretroviral therapy for while, but decided to cease taking the drugs earlier this year.