"The therapeutics arena has become extremely complex," with 14 approved drugs that can be used in various combinations to treat HIV, said Constance A. Benson, MD. "We have to take steps back a little bit to look at some of the long-term consequences of the therapies we are using."
The chair of the world's premier meeting of AIDS scientists, the 7th Conference on Retroviruses and Opportunistic Infections, made those remarks to the press Jan. 30. She said that much of the discussion would be around "refinements of drug combinations" and "the complications of those therapies."
The conference drew 3,200 researchers, a third from overseas, for four intense days of presentations and discussion in San Francisco. The meeting was held in Chicago the last two years and prior to that in Washington, D.C. Benson said that 1,700 abstracts were submitted for presentation but there was room to accept only half. Of those, most were "poster sessions" and just 122 were oral presentations.
Benson admitted, "We don't know when is the most appropriate point in time to intervene in the progression" of HIV. The power of existing therapies to limit viral replication is being balanced by a growing knowledge of risks and toxicities associated with long-term use of those drugs. She is "more comfortable not immediately starting therapy in early stages of disease. But that comment is qualified by a lot of individual characteristics that get taken into consideration."
Noted researcher David Ho, MD, vice chair of the conference, focused his remarks on more basic research. He said that current drugs work on the reverse transcriptase and protease functions of the virus lifecycle. This is the first meeting that will devote significant time to "fusion inhibitors," which block viral entry into the cell, and integrase inhibitors, which attack the other major stage of viral replication.
"The flavor of this year on the therapeutic side is structured treatment interruption," said Ho. The concept gained credence last year with initial data presented by Franco Lori, MD, a researcher who splits time between Georgetown University and a lab in Italy. Several other researchers have found tantalizing support for the approach, though in a very limited number of patients over a short duration of time. Much of that data will be presented at a "late breaker" session Feb. 2.
Benson cautions, "This is a concept that has not yet been proven. These are careful studies that should be done in very careful, very controlled settings." They are not for patients or physicians to try in a slap dash manner.