Could bone marrow transplants cure HIV? Two men who had procedure stop taking medication after virus 'disappears' from their blood
- Last year scientists announced that the two unnamed men no longer seemed to have the virus but they were still taking antiretroviral medication
- The men have now come off medication - one for 15 weeks and the other for seven - and still show no signs of having HIV virus
- Experts say it is too early to say that the men had been cured but that their progress was very encouraging
- Warned that virus may be hiding in other organs such as the liver, spleen or brain and could return months later, he warned.
Two men with HIV have been able to stop taking their medication after receiving bone marrow transplants.
Experts say it is too early to describe them as ‘cured’ – but the Aids virus shows no signs of returning in either patient.
The men, who had HIV for about 30 years, received transplants to treat blood cancer several years ago. One stopped taking anti-HIV drugs four months ago, while the other stopped seven weeks ago.
Both men had suffered with blood cancer and had undergone bone marrow transplants (marrow being prepared pictured) to treat that disease. No one expected the procedure to have such a dramatic and beneficial side effect
Their US doctors say keeping them on the drugs after their transplants first took place prevented their new supplies of healthy blood cells from becoming infected by HIV. The patients’ old, diseased cells were then attacked by the new ones.
The International Aids Society conference in Malaysia heard that now, even though the patients have stopped taking antiretroviral drugs, the virus cannot be detected in their blood. Normally, the disease can only be kept under control with lifelong treatment.
Working out why the bone marrow transplants had such a strong effect could lead to new treatments for the 34million living with Aids. An estimated 100,000 Britons have HIV, including 20,000 who have not been formally diagnosed.
Timothy Henrich, of the Brigham and Women’s Hospital in Boston, said the men ‘are doing very well’, but warned: ‘While these results are exciting, they do not yet indicate the men have been cured. Only time will tell.’
Experts say it is too early to say that the men are cured as virus (pictured) could be hiding in organs
One possibility is that the virus is ‘hiding’ in another part of the body, such as the liver or brain, and could re-emerge in the coming weeks.
Dr Michael Brady of the Terrence Higgins Trust stressed that bone marrow transplants are ‘complex and expensive’, and could be more dangerous than daily medication.
However, he added: ‘While this is by no means a workable cure, it does give researchers another sign-post in the direction of one.’
The first person reported to be cured of HIV, American Timothy Ray Brown, underwent a stem cell transplant in 2007 to treat his leukemia. He was reported by his German doctors to have been cured of HIV two years later.
Brown's doctors used a donor who had a rare genetic mutation that provides resistance against HIV. So far, no one has observed similar results using ordinary donor cells such as those given to the two Boston patients.
Kuritzkes said the patients will be put back on the drugs if there is a viral rebound.
A rebound will show that other sites are important reservoirs of infectious virus and new approaches to measuring these reservoirs will be needed in developing a cure, Henrich said.
‘These findings clearly provide important new information that might well alter the current thinking about HIV and gene therapy,’ Kevin Robert Frost, chief executive of The Foundation of AIDS Research, said in a statement.
'While stem cell transplantation is not a viable option for people with HIV on a broad scale because of its costs and complexity, these new cases could lead us to new approaches to treating, and ultimately even eradicating, HIV.'
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