UK patient 'free' of HIV after stem cell treatment

A UK male patient's HIV has become "undetectable" following a stem cell transplant -- in only the second such case of its kind in the world, scientists led by an Indian-origin researcher reported Tuesday in a case study published in the journal Nature.

The patient, who has not been named, was diagnosed with HIV in 2003 and advanced Hodgkin's lymphoma in 2012.

He had chemotherapy to treat the Hodgkin's cancer and, in addition, stem cells were implanted into the patient from a donor resistant to HIV, leading to both his cancer and HIV going into remission.

The patient, who was being treated for cancer, has now been in remission from HIV for 18 months and is no longer taking HIV drugs, the BBC reported.

"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 lead study author Professor Ravindra Gupta, from the University College London (UCL) in the UK.

Ten years ago, another patient in Berlin, Germany, received a bone-marrow transplant from a donor with natural immunity to the virus.

Both patients were treated with stem cell transplants from donors who carried a rare genetic mutation, known as CCR5-delta 32, that made them resistant to HIV.

However, researchers cautioned that it is too early to say the patient is "cured" of HIV.

Timothy Brown, said to be the first person to "beat" HIV/Aids, was given two transplants and total body irradiation (radiotherapy) for leukaemia - a much more aggressive treatment.

Researchers from the UCL, Imperial College London, Cambridge and Oxford Universities were all involved in the case, the report said.

Professor Eduardo Olavarria, also involved in the research, from Imperial College London, said the success of stem cell transplantation offered hope that new strategies could be developed to tackle the virus.

"The treatment is not appropriate as a standard HIV treatment because of the toxicity of chemotherapy, which in this case was required to treat the lymphoma," he added.

CCR5 is the most commonly used receptor by HIV-1 - the virus strain of HIV that dominates around the world - to enter cells.

However, a very small number of people who are resistant to HIV have two mutated copies of the CCR5 receptor.

This means the virus cannot penetrate cells in the body that it normally infects.

The London patient received stem cells from a donor with this specific genetic mutation, which made him resistant to HIV as well.

But a reservoir of cells carrying HIV can still remain in the body, in a resting state, for many years.

The UK researchers say it may be possible to use gene therapy to target the CCR5 receptor in people with HIV, now they know the Berlin patient's recovery was not a one-off.

Gupta added that the method used is not appropriate for all patients but offers hope for new treatment strategies, including gene therapies.

He and his colleagues will continue to monitor the man's condition, as it is still too early to say that he has been cured of HIV, CNN reported.

Almost one million people die annually from HIV-related causes. Treatment for HIV involves medications that suppress the virus, known as antiretroviral therapy, which people with HIV need to take for their entire lives.