AZT or Tenofovir for Patients with the K65R Mutation?

The K65R reverse transcriptase mutation decreases susceptibility to tenofovir, but in this retrospective study, AZT offered no virologic benefit over tenofovir as part of salvage therapy.

The K65R mutation in HIV confers a three- to four-fold decrease in phenotypic susceptibility to the nucleoside reverse transcriptase inhibitor (NRTI) tenofovir. However, its clinical impact has not been rigorously evaluated.

In this study (which was conducted in California and France, with partial support from the maker of tenofovir), researchers retrospectively identified 130 patients who had the K65R mutation in the setting of virologic failure and subsequently switched to a new antiretroviral regimen.

In the 12 weeks after salvage therapy was initiated, complete virologic response was seen in 58% of the patients receiving AZT and in 64% of those receiving tenofovir. After adjustment for a number of confounding variables (baseline viral loa…

Reviewing Authors

Jonathan Z. Li, MD

Paul E. Sax, MD

Disclosures

Consultant/Advisory BoardGilead Sciences; GlaxoSmithKline/ViiV; Merck; Shionogi

Grant/Research SupportNIH; Gilead Sciences; ViiV

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