For children infected with the AIDS virus, strict adherence to anti-HIV drug therapies may be even more important than it is for adults.
Newly published research led by Russell Van Dyke, professor of pediatric infectious diseases at the Tulane University School of Medicine in New Orleans, suggests HIV-positive children are more likely than adults to develop resistance to anti-AIDS drugs.
An abstract of the Van Dyke-led study was presented at the 2014 Conference on Retroviruses and Opportunistic Infections in Boston. The researchers followed nearly 450 HIV-positive children enrolled in the Pediatric HIV/AIDS Cohort Study.
Since 2005, the Pediatric HIV/AIDS Cohort Study network has been striving to answer two questions about children and adolescents and the AIDS virus: whether it is safe to give antiretroviral drugs to fetuses and infants, and the impact on adolescents of HIV infections they acquire from their mothers during or just after birth.
The study, conducted at 14 sites across the country, followed children who were 7 to 16.
It found that 74 percent of HIV-positive children in the United States had developed resistance to at least one of the five main classes of anti-HIV drugs. In addition, 30 percent were resistant to at least two classes of the drugs.
By contrast, nearly 36 percent of adults with HIV have resistance to one form of drug treatment and only 12 percent have resistance to at least two classes.
“The problem with drug resistance is that once you develop it, it never goes away,” said Van Dyke, who directs the Tulane/LSU Pediatric AIDS Clinical Trials Unit. “Some patients with very resistant virus have no effective treatment options. Resistant virus is the major reason for death among youth with perinatal HIV.”
The good news, according to Van Dyke, is most HIV-positive adolescents don’t face such a bleak resistance scenario. That’s because there are newer agents within all the anti-HIV drug classes that make it possible for doctors to employ “salvage” or “rescue” therapies on children who have developed resistances to other drugs.
The study found just one child who had resistance to all HIV drugs and only 18 percent had resistance to one drug from each of the three primary classes of HIV medications.
Nevertheless, one big take-away from the Tulane study is that it is important that children take the “cocktail” of multiple anti-AIDS drugs that have been prescribed for them when they are supposed to. Over the last 30 years doctors and researchers have found that failing to strictly follow HIV treatments is a prime cause of drug resistance.
“You develop resistance when you take some of your medications but not all,” Van Dyke said. “Then you’ve got virus that is replicating in the face of taking your medication. Lack of adherence is the major reason resistance develops.”
The U.S. Food and Drug Administration has approved three “single-pill” anti-HIV medications, taken once a day, for adults. It has not yet authorized their use to treat children.