In November 2008, Treatment Action Group, the Foundation for AIDS Research, and the FAIR Foundation sponsored a meeting of leading scientists in Washington, D.C., to discuss the possible avenues—and impediments—to finding a way to eliminate HIV from the body—or at least cause long-term, drug-free remission. Among the sponsors, the Workshop on Eliminating Viral Persistence and Eradicating HIV Infection was informally known as the “Cure Meeting.”
Hopes of permanently curing HIV infection deflated after it was discovered that the virus inserts its DNA into the DNA of its target immune cells. New viruses are made as a by-product of the cell’s transcribing DNA to perform its normal functions. Some of these infected immune cells can quietly hide in lymph nodes for years, harboring a hidden reservoir of virus. When a wave of powerful new treatments were approved in the mid-1990s, it was hoped that over time the reservoir cells would die off and the infection would eventually burn itself out. Mathematical estimations of this scenario soon showed that—even if perfect suppression could be achieved—it could take 20–60 years to eradicate HIV from the body with drugs alone. After that disappointment, hopes for a cure dimmed as science turned to the more realistic goals of improving treatments and discovering a vaccine.
In 2007, the first of a new class of drugs called integrase inhibitors was approved by the FDA. The new drugs work by preventing the viral DNA from inserting itself into the immune cell’s DNA and some think they may pose a nearly impenetrable barrier to new infections. The potency of integrase inhibitors has stimulated interest in bringing virus levels far lower than had been previously thought possible and has revived talk of eradicating HIV. But the long life of the infected reservoir cells is still a problem.
One approach to flushing the reservoir has been to stimulate the resting cells into action, thus luring out the hidden HIV so it becomes susceptible to antiviral drugs. Early attempts used agents that stimulated the immune system indiscriminately, and were scuttled by toxicity. Some scientists are now proposing ideas for stimulating hidden HIV-infected cells with greater precision. Others think it may be possible to identify the cells and specifically target them for destruction. Still others think it may be possible to permanently switch off mechanisms in the cells that HIV depends on for replication.
Many scientists say they have good ideas that need to be tested in people but cannot obtain funding because the current grant mechanisms of the National Institutes for Health (NIH) are not oriented toward supporting translational research that moves therapies from the laboratory to the clinic. Other barriers involve FDA guidelines for how research can be performed on people; some of these requirements limit what university-based scientists can accomplish on limited budgets.
The Cure Meeting invited key leaders from the NIH; other, nongovernmental funders of AIDS research; top scientists working in the field of HIV persistence and eradication; doctors involved with cutting-edge HIV studies; and HIV treatment activists. Discussion was divided between roadblocks and opportunities, both in the science and in the funding and practical spheres.
TAG plans to follow up on the directions outlined at the meeting with an advocacy campaign aimed at revitalizing research to permanently defeat HIV.