Researchers had thought they had eliminated HIV in two patients using bone marrow transplants, but the virus is reported to have returned in both cases.
The patients were temporarily "cured" several years ago. They had received bone marrow transplants to treat cancer, and later medical experts discovered the virus was undetectable in their bodies, the Boston Globe reported.
The patients stopped taking their antiretroviral medication after making the discovery. HIV has been known to "hide" in the body, but medical experts have detected it once again in the two patients.
Even though this new development was extremely disappointing to both medical practitioners and patients the researchers decided to release their conclusions as soon as possible.
"We felt it would be scientifically unfair to not let people know how things are going, especially for potential patients," Doctor Timothy Henrich of Brigham and Women's Hospital, told the Boston Globe.
The patients had agreed to stop taking their antiretroviral medications in order to see if the transplants really had treated their condition; researchers conducted blood tests to keep an eye on them.
After one patient had been off of their medication for seven weeks and the other nine, the researchers were happy to report there was still no trace of the virus.
In August the virus was determined to have returned in one patient, who resumed their antiretroviral treatment. This month the virus was also detected in the second patient, who also resumed taking their medication.
The study suggests HIV can lurk "deeper" in the body than researchers had suspected.
"This suggests that we need to look deeper, or we need to be looking in other tissues . . . the liver, gut, and brain," Henrich said, the Boston Globe reported. "These are all potential sources, but it's very difficult to obtain tissue from these places so we don't do that routinely."
In 2009 patient Timothy Ray Brown (the "Berlin Patient") was reported to have been cured of the virus, also through a bone marrow transplant. The difference was Brown went through harsh radiation treatments before the transplant, these types of attacks are not recommended for the average patient.
The experts said bone marrow transplants are dangerous and painful; they are not recommended for HIC treatment, especially in patients that have not been diagnosed with cancer.
"This is certainly telling us a lot about persistence, what we need to do, and how low we need to drop the levels of HIV reservoirs in order to allow patients to achieve remission," Doctor Katherine Luzuriaga, professor of molecular medicine, pediatrics and medicine at UMass Medical School, said, the Boston Globe reported.
The team plans to broaden their study, in hopes of uncovering safer and more effective HIV treatments in the future.
"We go back to the drawing board," Henrich said. "It's exciting science, even if it's not the outcome we would have liked."
