Almost two decades after the original "Berlin patient," a second patient has achieved sustained HIV remission, this time for 18 months after interruption in antiretroviral therapy, following an allogeneic hematopoietic stem-cell transplantation procedure.
In this exclusive 鶹ý video, , from the University of California, San Francisco, explains why he is hopeful that what we're going to see with the so-called "London patient" is continuing what we saw with Timothy Ray Brown.
Following is a transcript of his remarks:
I think we're considering this an antiretroviral-free HIV remission, in a sense stopping antiretroviral therapy and not seeing rapid or even low-level rebound of virus within the blood. What we've seen so far after 18 months is that seems to be the case after stopping therapy. It very much looks like Timothy Ray Brown, where there's really no detectable HIV especially from using clinical assays and routine standard testing in the blood. Whether this is going to be permanent, I think we need another about six months to two years to really know if it's going to. I'm actually optimistic. I think that the London patient will be very much like Timothy Ray Brown, and I certainly hope so as well. It would be exciting, obviously, for our field. Two is better than one. More than two is even better, but I think at this point there's a small chance that there could be viral recrudescence, although I think that most of us are optimistic that we will see something very similar to Timothy Ray Brown.
Timothy Ray Brown did have a little bit more intensity conditioning for the transplantation. Whether that actually made a difference in terms of the HIV-free remission, or excuse me, the antiretroviral free HIV remission, [a] little less clear. I think that the main point is that [with] both individuals, the donor cells have come over and become essentially a 100% of their blood cells, and that can happen with any type of conditioning regimen. But because both of them achieved this, the complete donor takeover in the blood, that has really made us excited that what we're going to see is continuing what we saw with Timothy Ray Brown.
Now obviously, Timothy Ray Brown had some complications from the two transplants that he did receive, and I really hope that these types of complications don't also happen to the London participant. But stem-cell transplant is not without risk and there can be short and even longer-term consequences of allogeneic stem-cell transplantation. I really hope that he will do well.
This case really reproduces what we saw with Timothy Ray Brown. In terms of the amount of new information, in terms of what actually is causing this HIV remission I think is somewhat limited, but what I do want to stress is that the case is exciting because it tells us that we're on the right track. It says that there are other therapies that do not involve full stem-cell transplantation. We saw a few of them today in the morning sessions. For example, gene-modification therapy, modifying stem cells to reduce CCR5 expression, that there are ways of going about and doing similar types of treatments, but without the morbidity and without that. I think it is therefore exciting and really invigorating for our field to know that we're on the right track. It's going to be slow. It's going to be difficult, but at least we know that we're going in the right direction.