A man in London has become the second ever known person to be cleared of HIV after receiving a bone marrow transplant from a donor resistant to the disease.
The patient received a bone marrow transplant 3 years ago from a donor with a rare genetic mutation that resists the HIV infection, 18 months after the transplant the patient was able to come off his antiretroviral drugs. With recently conducted tests still showing no trace of his previous HIV infection.
“There is no virus there that we can measure. We can’t detect anything,” said Ravindra Gupta, a professor and HIV biologist who co-led a team of doctors treating the man. He described his patient as “functionally cured” and “in remission”, but cautioned: “It’s too early to say he’s cured.“
This is the second known case of a functional cure for HIV. American Timothy Brown who received similar treatment in back in 2007 in Germany. He was also cleared of the HIV virus and is still HIV-free.
Statistics suggest that 37 million people are infected with HIV and Aids globally, resulting in 35million people deaths from the disease since in the 1980s. Though both patients have been cured of the virus, experts say that the procedure is still expensive, complex and risky to be rolled out worldwide. Exact match donors would have to be found in the tiny proportion of people – most of them of northern European descent – who have the CCR5 mutation.
Specialists said it was not yet clear whether the CCR5 resistance is the only key – or whether the graft-versus-host disease may have been just as important. The Berlin and London patients both had this complication, which may have played a role in the loss of HIV-infected cells.
He said his team planned to use these findings to explore potential HIV treatment strategies. “We need to understand if we could knock out this [CCR5] receptor in people with HIV, which may be possible with gene therapy,” he said.