Daily Times

Both patients underwent bone marrow transplants to treat blood cancers, receiving stem cells from donors with a genetic mutation present in less than one percent of Europeans that prevents HIV from taking hold.

“It is a landmark. After 10 years of not being able to replicate (the first case), people were wondering if this was a fluke,” said lead author Ravindra Gupta, a professor at the University of Cambridge.

“I think it is important to reaffirm that this is real and it can be done,” Gupta told AFP.

The findings will be presented later Tuesday at a medical conference in Seattle, Washington.

Millions of people infected with HIV around the globe keep the disease in check with so-called antiretroviral therapy (ARV), but the treatment does not rid patients of the virus.

The first sustained remission survivor, announced in 2009 as “the Berlin patient” and later named as American Timothy Brown, was given two transplants and underwent total body irradiation to treat leukaemia — a process that nearly killed him.

Gupta said that while a second successful transplant did not constitute a generalised cure, his team’s work showed that even milder forms of treatment can achieve full HIV remission.

“There are a number of learning points here,” he said. “Radiation has a lot of side-effects and leads to a delayed recovery of the bone marrow, so it’s really good that we’ve shown you don’t need radiation.

Both patients received stem cell transplants from donors carrying a genetic mutation that prevents expression of an HIV receptor, known as CCR5.

The London patient was diagnosed with HIV infection in 2003 and had been on antiretroviral therapy since 2012.

Later that year, he was diagnosed with advanced Hodgkin’s Lymphoma, a deadly cancer.

“We know that CCR5 can be knocked out without any serious consequences because people are walking around without that gene.”

CCR5 was the target in the genome of the controversial gene-edited twins born last year in China, whose father is HIV-positive.

Experts cautiously welcomed Tuesday’s announcement, with Mark Dybul, co-chair of the Towards an HIV Cure initiative, calling the London case “as important as it is exciting”.

The International AIDS Society said in a statement Tuesday that results from the second patient “reaffirm our belief that there exists a proof of concept that HIV is curable”.

– New communities –

After the bone marrow transplant, the London patient remained on ARV for 16 months, at which point treatment was stopped.

Regular testing has confirmed that the patient’s viral load remained undetectable since then.

Gupta said he hoped to expand research on the stem-cell transplant technique to focus on communities in Africa, where the HIV-beating mutation does not naturally occur.

“Expanding remission to populations that are affected disproportionately is quite important,” he told AFP.