Nearly half of HIV-positive patients who initially respond to HIV antiretroviral medications experience a rebound in viral levels, according to a study presented Tuesday at the Sixth International Congress on Drug Therapy in HIV Infection in Glasgow, Scotland, Reuters Health reports. Researchers from University College in London examined 1,470 patients whose viral loads had initially dropped to undetectable levels after beginning an anti-HIV drug regiment. Participants' viral levels were measured at six-month intervals.
According to the study, about 46% of patients experienced a rebound in viral levels, with the vast majority of them experiencing a rebound within six months of achieving undetectable viral loads. Patients taking five or more drugs and treatment-experienced patients were more likely to experience a viral rebound, while older patients, patients who had maintained undetectable viral loads for two years or longer, and patients with higher T-cell counts were less likely to experience a rebound.