Stanford researchers are urging caution in the use of one of the AIDS drug regimens recommended by the World Health Organization, saying this particular mix of medications has a relatively high failure rate and could lead to problems with drug resistance.
In 2010, the WHO revised its list of recommended drug regimens for newly diagnosed patients, suggesting four different combinations; each contains tenofovir plus two other drugs. Postdoctoral scholar Michele Tang, MD, and her colleagues reviewed all the available literature on these regimens and found that one combination, which included lamividine (3TC) and nevapirine (NVP), performed very poorly, even compared to some of the older drug cocktails.
The drug combination had a relatively high failure rate, with two studies forced to stop early because of poor performance and problems with resistance, Tang said. The combination didn’t even do as well as other therapies containing AZT, one of the early AIDS drugs that is more toxic.
“We believe we have a responsibility to developing countries, where patients often receive less laboratory monitoring, that the regimens we recommend are well studied and proven to be virologically efficacious,” Tang said. “Thus, TDF/3TC/NVP combination should be further studied before it is widely used in resource limited settings.”
Tang presented the results this week at the 6th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention, held in Rome. Tang said she is concerned that large numbers of patients in the developing world could receive this drug combination, leading to poor patient outcomes and widespread problems of resistance. The drug combination is not generally used in this country, with the Department of Health and Human Services saying it should be applied with caution, she said.
Her co-authors on the study are Robert Shafer, MD, associate professor of medicine at Stanford, and Phyllis Kanki, PhD, a professor of immunology and infectious disease at Harvard School of Public Health.