2 Men With HIV Are Off Drugs, Seem Virus-Free After undergoing a bone marrow transplant By Evann Gastaldo, Newser Staff Posted Jul 3, 2013 7:43 AM CDT Updated Jul 3, 2013 7:53 AM CDT 11 comments Comments Timothy Henrich of the Harvard-affiliated Brigham and Women's Hospital in Boston speaks at the International AIDS Society Conference 2013 in Kuala Lumpur, Malaysia, Wednesday, July 3, 2013. (AP Photo/Lai Seng Sin) (Newser) – The two men who saw HIV seemingly vanish from their blood after getting bone marrow transplants to treat their blood cancer are still apparently virus-free and feeling "great"—weeks after they stopped taking anti-retroviral drugs. Researchers gave the encouraging update today at the International AIDS Society Conference in Malaysia, but doctors are being careful not to use the word "cured," since the men have been off drugs a relatively short period of time: seven and 15 weeks, respectively. "If these patients are able to stay without detectable HIV for at least a year, maybe a year and a half, after we stop treatment, then the chances of the virus coming back are very small," a lead researcher tells AFP. Their blood is being tested weekly, and even their intestinal tissue, where HIV seemingly hides, has been tested, the Boston Globe reports. But "HIV could still be hiding in the brain, gut, or lymph nodes," warns the study leader. Of course, as the New York Times puts it, the news is of "no practical use" to most of the people suffering from HIV around the world. The transplant procedure is extremely dangerous, and can only be ethically used on someone already at risk of dying from blood cancer. (In fact, the third patient in the study died after his cancer returned.) Even so, the results are encouraging, and could inform attempts to genetically re-engineer HIV patients' cells; two teams are apparently working on this. The case is similar to that of Timothy Ray Brown, who was apparently cured of HIV following a bone marrow transplant, but he had leukemia (these patients had Hodgkin's lymphoma) and he received marrow containing a mutation that protects against HIV (these patients did not). More encouraging news from the conference: The HIV-positive baby who was put on anti-retrovirals when she was just days old is still free of the virus, 15 months after stopping treatment.