A patient diagnosed with HIV and treated with stem cell transplant has been in remission for 18 months after his antiretroviral therapy (ARV) was discontinued, according to a press release Tuesday posted on the website of the University of Cambridge.
Regular testing confirmed that the patient's HIV (human immunodeficiency virus) viral load remained "undetectable", and he has been in remission for 18 months since ceasing ARV therapy (35 months post-transplant), according to the press release.
But the team emphasized that it is too early to say with certainty that the patient has been cured of HIV, and that they will continue to monitor the patient's condition.
The case report is carried out by researchers at University College London (UCL) and Imperial College London, together with teams at the University of Cambridge and the University of Oxford.
The breakthrough result comes 10 years after the first such case, known as the "Berlin Patient", who was also reported to be in sustained remission without ARV.
The male patient in Britain was diagnosed with HIV infection in 2003 and on antiretroviral therapy since 2012, according to the report. Later in 2012, he was diagnosed with advanced Hodgkin's Lymphoma.
In addition to chemotherapy, in 2016 he underwent a haematopoietic stem cell transplant from a donor with two copies of the genetic mutation, or "allele", that prevents expression of CCR5. CCR5 is the most commonly used receptor by HIV-1, the most common and most harmful type of HIV. People who have two mutated copies of the CCR5 allele are resistant to the HIV-1 virus strain that uses this receptor, as the virus cannot enter host cells.
"Finding a way to eliminate the virus entirely is an urgent global priority, but is particularly difficult because the virus integrates into the white blood cells of its host," said the study's lead author, Professor Ravindra Gupta from the University of Cambridge, who led the study while at UCL.
"By achieving remission in a second patient using a similar approach, we have shown that the Berlin Patient was not an anomaly, and that it really was the treatment approaches that eliminated HIV in these two people," said Professor Gupta.
However, the researchers caution that the approach is not appropriate as a standard HIV treatment due to the toxicity of chemotherapy, but it offers hope for new treatment strategies that might eliminate HIV altogether.
