title: Determinants of sustained viral suppression in HIV-infected patients with self-reported poor adherence to antiretroviral therapy.
abstract: BACKGROUND
  Good adherence to antiretroviral therapy (ART) is critical for successful HIV treatment. However, some patients remain virologically suppressed despite suboptimal adherence. We hypothesized that this could result from host genetic factors influencing drug levels.
  
  
  METHODS
  Eligible individuals were Caucasians treated with efavirenz (EFV) and/or boosted lopinavir (LPV/r) with self-reported poor adherence, defined as missing doses of ART at least weekly for more than 6 months. Participants were genotyped for single nucleotide polymorphisms (SNPs) in candidate genes previously reported to decrease EFV (rs3745274, rs35303484, rs35979566 in CYP2B6) and LPV/r clearance (rs4149056 in SLCO1B1, rs6945984 in CYP3A, rs717620 in ABCC2). Viral suppression was defined as having HIV-1 RNA <400 copies/ml throughout the study period.
  
  
  RESULTS
  From January 2003 until May 2009, 37 individuals on EFV (28 suppressed and 9 not suppressed) and 69 on LPV/r (38 suppressed and 31 not suppressed) were eligible. The poor adherence period was a median of 32 weeks with 18.9% of EFV and 20.3% of LPV/r patients reporting missed doses on a daily basis. The tested SNPs were not determinant for viral suppression. Reporting missing >1 dose/week was associated with a lower probability of viral suppression compared to missing 1 dose/week (EFV: odds ratio (OR) 0.11, 95% confidence interval (CI): 0.01-0.99; LPV/r: OR 0.29, 95% CI: 0.09-0.94). In both groups, the probability of remaining suppressed increased with the duration of continuous suppression prior to the poor adherence period (EFV: OR 3.40, 95% CI: 0.62-18.75; LPV/r: OR 5.65, 95% CI: 1.82-17.56).
  
  
  CONCLUSIONS
  The investigated genetic variants did not play a significant role in the sustained viral suppression of individuals with suboptimal adherence. Risk of failure decreased with longer duration of viral suppression in this population.
authors.affiliation: Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital of Basel, Basel, Switzerland.
authors.forename: Tracy R
authors.initials: TR
authors.lastname: Glass
authors.forename: Margalida
authors.initials: M
authors.lastname: Rotger
authors.forename: Amalio
authors.initials: A
authors.lastname: Telenti
authors.forename: Laurent
authors.initials: L
authors.lastname: Decosterd
authors.forename: Chantal
authors.initials: C
authors.lastname: Csajka
authors.forename: Heiner C
authors.initials: HC
authors.lastname: Bucher
authors.forename: Huldrych F
authors.initials: HF
authors.lastname: Günthard
authors.forename: Martin
authors.initials: M
authors.lastname: Rickenbach
authors.forename: Dunja
authors.initials: D
authors.lastname: Nicca
authors.forename: Bernard
authors.initials: B
authors.lastname: Hirschel
authors.forename: Enos
authors.initials: E
authors.lastname: Bernasconi
authors.forename: Gilles
authors.initials: G
authors.lastname: Wandeler
authors.forename: Manuel
authors.initials: M
authors.lastname: Battegay
authors.forename: Catia
authors.initials: C
authors.lastname: Marzolini
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D015658:HIV Infections / Q000188:drug therapy* / Q000235:genetics / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000089762:Multidrug Resistance-Associated Protein 2; D010349:Patient Compliance / Q000706:statistics & numerical data*; D057566:Self Report; D013997:Time Factors
chemical_list: C000715087:ABCC2 protein, human; D019380:Anti-HIV Agents; D000089762:Multidrug Resistance-Associated Protein 2