title: Reappearance of minority K103N HIV-1 variants after interruption of ART initiated during primary HIV-1 infection.
abstract: BACKGROUND
  In the Zurich Primary HIV infection study (ZPHI), minority drug-resistant HIV-1 variants were detected in some acutely HIV-1-infected patients prior to initiation of early antiretroviral therapy (ART). Here, we investigated the reappearance of minority K103N and M184V HIV-1 variants in these patients who interrupted efficient early ART after 8-27 months according to the study protocol. These mutations are key mutations conferring drug resistance to reverse transcriptase inhibitors and they belong to the most commonly transmitted drug resistance mutations.
  
  
  RESULTS
  Early ART was offered to acutely HIV-1-infected patients enrolled in the longitudinal prospective ZPHI study. Six patients harboring and eleven patients not harboring drug-resistant viruses at low frequencies prior to ART were included in this substudy. Minority K103N and M184V HIV-1 variants were quantified in longitudinal plasma samples after treatment interruption by allele-specific real-time PCR. All 17 patients were infected with HIV-1 subtype B between 04/2003 and 09/2005 and received LPV/r+AZT+3TC during primary HIV-1 infection (PHI). Minority K103N HIV-1 variants reappeared after cessation of ART in two of four patients harboring this variant during PHI and even persisted in one of those patients at frequencies similar to the frequency observed prior to ART (<1%). The K103N mutation did not appear during treatment interruption in any other patient. Minority M184V HIV-1 variants were detected in two patients after ART interruption, one harboring and one not harboring these variants prior to ART.
  
  
  CONCLUSIONS
  Minority K103N HIV-1 variants, present in acutely HIV-1 infected patients prior to early ART, can reappear and persist after interruption of suppressive ART containing two nucleoside/nucleotide analogue reverse transcriptase inhibitors and a ritonavir-boosted protease inhibitor.
  
  
  BACKGROUND
  Clinicaltrials.gov NCT00537966.
authors.affiliation: Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland. Karin.Metzner@usz.ch
authors.forename: Karin J
authors.initials: KJ
authors.lastname: Metzner
authors.forename: Christine
authors.initials: C
authors.lastname: Leemann
authors.forename: Francesca
authors.initials: F
authors.lastname: Di Giallonardo
authors.forename: Christina
authors.initials: C
authors.lastname: Grube
authors.forename: Alexandra U
authors.initials: AU
authors.lastname: Scherrer
authors.forename: Dominique
authors.initials: D
authors.lastname: Braun
authors.forename: Herbert
authors.initials: H
authors.lastname: Kuster
authors.forename: Rainer
authors.initials: R
authors.lastname: Weber
authors.forename: Huldrych F
authors.initials: HF
authors.lastname: Guenthard
mesh_terms: D023241:Antiretroviral Therapy, Highly Active; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007700:Kinetics; D008297:Male; D009154:Mutation / Q000235:genetics*