In the first study to show a low level of viral activity in children using the therapy, called HAART (highly active anti-retroviral therapy), a team led by Children's Center infectious disease researcher Deborah Persaud, M.D., says that bloodstream signatures of HIV-1 revealed no genetic signs that the virus was developing resistance. The finding, published in this week's Journal of the American Medical Association, has implications for the design and future treatment strategies in fighting the onset of AIDS.
"Going into the study, we thought it was possible that even low levels of virus activity could result in the evolution of resistance to HAART drugs," Persaud says. "But both the children and adults in our study showed that the therapy is working."
The report also shows that occasional increases in apparent virus activity, called "blips," do not necessarily indicate the virus is resisting the protease inhibitors and anti-retroviral drugs that make up HAART.
From the blood samples of 20 study participants, all of whom had been on HAART at least 25 months, the research team looked for the unique genetic signature left by very low levels of HIV-1, a virus that inserts itself into the human genome and begins replicating as though it were any other set of human genes.
The researchers compared each viral genetic sequence to other viral sequences from the same patient, to other patients' viral sequences and to sequences that represent drug-resistant viruses. The researchers found that viral replication and mutation had remained suppressed by HAART. Two of the 20 study participants, who responded less than optimally to HAART
Contact: David Bricker
Johns Hopkins Medical Institutions