Temporary Increases in HIV Viral Load Not Indicative of Waning Effectiveness of Antiretroviral Treatment, Study Says
Sudden increases in the viral loads of HIV-positive people taking antiretroviral drugs usually are harmless, temporary "blips" that do not indicate that the treatment is becoming less effective, according to a study published in the Feb. 16 issue of the Journal of the American Medical Association, Reuters reports (Reuters, 2/15). Dr. Richard Nettles and colleagues at Johns Hopkins University School of Medicine every few days for three to four months between June 2003 and February 2004 collected and analyzed blood samples from 10 HIV-positive people taking antiretroviral drugs whose viral loads had been less than 50 copies per milliliter of blood for at least six months since beginning treatment. Blips -- defined as increases in viral load to 50 or more copies per milliliter without a change in treatment -- were detected in nine of the 10 patients (BBC News, 2/16). According to the researchers, the blips -- which on average lasted less than three days -- had "no connection" to drug resistance except in cases when a patient's viral load increased to 200 or more copies per milliliter or if the increase persisted in repeated tests, Scripps Howard/Long Island Newsday (Scripps Howard/Long Island Newsday, 2/16). Researchers also found no evidence that viral mutations were taking place (Reuters, 2/15). While the study found a "margina[l]" association between blips in viral load and nonadherence to antiretroviral therapy, they did not occur in relation to illness, vaccination or antiretroviral drug concentrations, according to the study. Frequency of blips also was not associated with demographic, clinical or treatment variables, according to the study (Nettles et al., JAMA, 2/16).
Author Comment, Reaction
"These results should provide relief to hundreds of thousands of HIV-positive patients in the United States currently taking drug therapy ... and reassure them their medications have not failed," Dr. Robert Siliciano, JHU professor and senior author of the study, said (Scripps Howard/Long Island Newsday, 2/16). "Resistance to HIV drugs is a real cause for concern due to the difficulty of adhering to strict drug regimens and the ability of the HIV virus to mutate," Yusef Azad, policy director at the British HIV/AIDS advocacy group National AIDS Trust, said, adding, "However, this research shows that it is important not to jump to hasty conclusions based on slight changes in viral load" (BBC News, 2/16).