BY Benjamin Ryan
October 08 2009 10:00 AM ET
Thus far, Ronald T. Mitsuyasu, MD, director of the University of California, Los Angeles, Center for Clinical AIDS Research and Education, has made the most progress with his research. He has manipulated the stem cells in his patients to produce T cells better equipped to inactivate HIV genes. He has since published the first randomized, double-blind study that proves it's possible to safely use genetic therapy to lower viral load and to raise T cells during a structured treatment interruption.
“This is a very new field with very little data available, and so I do not want to get patients' hopes up too high, since it will take a long time for this therapy to be an effective and feasible way to treat HIV on a routine basis,” Mitsuyasu cautions, noting that his results were very modest.
Researchers and treatment advocates further caution that gene therapy comes with potential unknown risks.
“I think that for anybody who's thinking about participating in a trial,” Jefferys says, “one thing to think about ahead of time is the fact that they're going to want to keep track of you for a long time and that there are potential risks that they might just not know about yet.”
Outside of the scientific difficulties, the success of such new treatments largely depends on money. Currently, there isn't much of it to spend on research. The Bill and Melinda Gates Foundation, for example, which has spent more than half a billion dollars in the search for an HIV vaccine, has so far contributed a comparatively modest $14 million to this field of research, all in the form of a single grant to David Baltimore at Cal Tech.
On the back end of the financial problem is the issue of accessibility. The current method of taking cells out of the body and putting them back in is labor intensive and could cost tens of thousands of dollars per treatment. Researchers agree that they must discover a way to inject a gene therapy into HIVers that will find the immune cells and change their genetic makeup inside the body, not in the laboratory. This one-step process would greatly reduce the cost.
But even if such a single injection is itself still costly, genetic therapy could save money over time.
“If you're showing that you're going to improve people's quality of life and you're going to reduce their drug expenditures because they could have five years off day-to-day drug therapy,” Jefferys says, “then you're looking at something that could really be financially practical.”