BIlbao. An international group including renowned ICREA-IrsiCaixa researcher Javier Martínez Picado has managed to eradicate all signs of the Aids virus from the body of a patient through a bone marrow transplant. It is only the second time this has been achieved. Until now, the only person to have been cured through this technique was Timothy Brown, an American who lives in Germany, who until his name was made public five years ago was known as 'the Berlin patient'. That was in 2008 and it was described as an isolated case, and very difficult to replicate. However, it opened the door to hopes that one day a cure for HIV would be possible, and that now appears more feasible.
The objective has been achieved by repeating, in someone now known as 'the London patient', the same therapy as the one which cured Brown, but with slight differences. This was also an HIV patient who had to be treated for a lymphoma (a malign tumor of the lymphatic glands) through a transplant of hematopoietic progenitor cells, or, which is the same thing, a bone marrow transplant. Now, as before, the procedure has managed to remove at a stroke all signs of the virus in the patient's blood.
The London patient, whose identity is being kept anonymous at present, has had no sign of Aids in his blood for 18 months, but even so the doctors prefer to remain cautious. In theory, the existence of analyses showing that there is no sign of HIV in his veins would imply that he is cured: if there is no infection, there is no illness, but they prefer not to celebrate too soon: it is always possible that the virus, which has a strong ability to mutate and hide, could reappear.
"We need to be prudent and we believe it is too soon to talk of a cure," said Javier Martínez-Picado at the press conference. "We know of previous cases which were not successful, and the virus reappeared within a year. What we can say is that this patient has needed no medication for a year and a half now".
The stories of the Berlin and London patients are slightly different, although they appear very similar, and these differences make the second case much more hopeful. The American's transplant worked because the donor was part of the one per cent of the population who lack a protein called CCR5, which is one of the ways the virus enters the blood cells. At the time the therapy was thought unsuitable for most patients not only because of the high cost but because it would be impossible to find compatible donors for every patient in the world. So what has changed?
Something as simple as the fact that it was not as difficult as it seemed. The London patient's Aids virus was removed with a single transplant, while his predecessor needed two operations. Also, ten years later, the preparatory measures for surgery in this case were much less aggressive, and the scientists were encouraged by the fact that both patients overcame a common complication, graft versus host syndrome. "That also confirms that the Berlin patient wasn't a one-off," said Martínez-Picado. "We believe it is possible to achieve total remission of the virus, without the need for aggressive treatments".