A second patient was cured of HIV after treatment with stem cell transplantation, doctors said on Tuesday, after of which there is no trace of infection 30 months after stopping traditional treatment.
The so-called “London patient”, a cancer patient from Venezuela, made headlines last year when researchers at the University of Cambridge reported that they had not found traces of the AIDS-causing virus in their blood 18 months ago.
Lead author of the study Ravindra Gupta, published in The Lancet HIV, said the new test results were “even more remarkable” and probably demonstrated that the patient was cured.
“We tested a considerable set of sites where HIV likes to hide and all are practically negative for an active virus”.
The patient, who revealed his identity early this week as Adam Castillejo, 40 years of age, was diagnosed with HIV in 2003 and has been taking medication to keep the disease under control since 2012.
Later that year, he was diagnosed with advanced Hodgkin’s lymphoma, a deadly cancer.
In 2016, he underwent a bone marrow transplant to treat blood cancer, receiving stem cells from donors with a genetic mutation present in less than one percent of Europeans that prevent HIV from controlling itself.
He becomes the second person to be cured of HIV after American Timothy Brown, known as the “Berlin Patient”, recovered from HIV in 2011 after similar treatment.
Viral tests of brain fluid, intestinal tissue and lymphoid tissue of Castillejo more than two years after stopping antiretroviral treatment showed no active infection.
Gupta said the tests discovered HIV “fossils” – fragments of the virus that were now unable to reproduce and therefore were safe.
“We expected that,” he said.
“It is very difficult to imagine that every trace of a virus that infects billions of cells has been eliminated from the body.”
– Ethical dilemma –
The researchers warned that the advance was not a widespread cure for HIV, which leads to nearly one million deaths each year.
Castillejo’s treatment was a “last resort” as his blood cancer would likely kill him without intervention, according to Gupta.
The Cambridge doctor said there were “several other” patients who had undergone similar treatment, but who were in lesser remission.
“There will probably be more, but they will take time,” he said.
Researchers are currently evaluating whether or not patients suffering from forms resistant to HIV drugs may be eligible for stem cell transplants in the future, something Gupta said would require careful ethical consideration.
“You would have to consider the fact that there is a 10% death rate when doing a stem cell transplant against the risk of death if we do nothing,” he said.
Commenting on the Lancet study, Sharon Lewin, an infectious disease specialist at the University of Melbourne, said the findings could provide comfort to patients.
But she advised caution.
“Given the large number of cells sampled here and the absence of an intact virus, is the London patient cured?” she said.
“Unfortunately, in the end, only time will tell.”