Highly Sensitive Resistance Testing: Relevant, but Ready for the Clinic?

Standard population-based sequencing to determine genotypic resistance changes is relatively insensitive in detecting low-frequency HIV drug-resistance mutations. This insensitivity might be particularly important when assessing for transmitted drug resistance before treatment initiation. How common are these low-frequency mutations in treatment-naive patients, and do they influence treatment outcomes? To find out, investigators conducted a series of analyses using a real-time PCR assay (for which 2 of them have a patent pending).

The first (cross-sectional) analysis involved 205 newly diagnosed, treatment-naive patients in the U.S. who had no detectable mutations by standard genotyping. Overall, the assay detected one or more mutations in 3…