amfAR Convenes Experts to Discuss Potential Cure
By Rowena Johnston, Ph.D.
December 15, 2005—Is a cure for HIV possible? And if so, which steps will lead us towards that goal?
These were questions addressed by a group of 12 scientists who gathered on December 5 for an amfAR-convened think tank on HIV persistence. More specifically, these researchers volunteered their time and expertise to discuss how amfAR’s innovative research program, with its ability to react quickly to emerging research issues, can help generate new advances and resources to help move the field forward.
HIV persistence presents a unique challenge to scientists. While most infections are cleared by the immune system, there has never been a documented case of an HIV-positive person ridding their body of the virus, despite vigorous attempts by the immune system to do so. And although fairly sophisticated anti-HIV therapy is available today, these drugs do not reach – and therefore cannot destroy – every last virus in the person’s body. This means HIV is a life-long condition, one that almost always leads to AIDS and death.
HIV persists because of reservoirs of virus in the body. While we know that virus hiding in these reservoirs is impervious to anti-HIV therapy, many unanswered questions remain. Take, for example, a person who has been on therapy for years with well-suppressed HIV—levels of virus so low that standard tests no longer detect it. If taken off therapy, virus levels will shoot up to levels seen in untreated patients within just a few weeks. Where does this virus come from? In other words, are there specific regions of the body that are responsible for this rapid rebound in viral load? Is there a type of cell that is particularly good at harboring virus in reservoirs, waiting for an opportunity to spark prolific growth of the virus once drug therapy is removed?
Other unanswered questions may influence how we treat HIV infection and our priorities for developing technologies to detect HIV infection sooner. We know that reservoirs of HIV are established very soon after infection. What if there were some way we could intervene promptly at this early stage? Could we change or even eliminate the establishment of reservoirs altogether? Even if we had some tool that could act early in infection to reduce or eliminate viral reservoirs, we would need the means to detect acute infection so that doctors could intervene in time. Current HIV tests do not detect HIV infection until as many as 6 months after infection, by which time viral reservoirs are well and truly established.
Several key issues were identified at the amfAR think tank, and more importantly, participants suggested the most pressing next steps for amfAR to take. amfAR will soon release a Request For Proposals, soliciting research ideas from scientists around the world addressing the problem of HIV persistence and possible ways to tackle it.
amfAR’s research program is driven by the recognition that we need two things to bring about an end to the HIV/AIDS pandemic: a way to prevent new infections—ideally a vaccine—and a cure. But a vaccine is many years away and will come too late for the tens of millions of people already living with the virus. That number will only continue to grow. Meanwhile we must continue to pursue a cure, if one is possible, recognizing that there is much work yet to be done.
Dr. Johnston is director of research at amfAR.