NEW HAVEN, Conn., June 20 (UPI)

The fraction of HIV patients with undetectable drug-resistant forms of HIV is higher than previously thought, according to U.S. researchers. Yale School of Medicine researcher Dr. Michael Kozal used an innovative genome sequencing technology that quickly detects rare viral mutations and found the fraction of HIV patients that harbored resistance mutations is at least twice as high as previously thought. These low frequency resistant viral strains are not detectable by current resistance testing methods used in the clinic, Kozal said in a statement. Kozal and his team examined samples from 258 subjects of a large multi-center five-year U.S. trial comparing three different approaches to antiretroviral therapy. Current technology used in the clinic may miss many low-level resistant HIV strains that can grow rapidly under drug selection pressure and lead to therapy failure, according to the findings presented at the 16th International HIV Drug Resistance Workshop in Barbados.

Copyright 2007 by United Press International