title: Virological failure rates and HIV-1 drug resistance patterns in patients on first-line antiretroviral treatment in semirural and rural Gabon.
abstract: BACKGROUND
  As antiretroviral treatment (ART) continues to expand in resource-limited countries, the emergence of HIV drug resistance mutations (DRMs) is challenging in these settings. In Gabon (central Africa), no study has yet reported the virological effectiveness of initial ART given through routine HIV care.
  
  
  METHODS
  Following the World Health Organization (WHO) recommendations, a cross-sectional study with a one-time HIV-1 RNA viral load (VL) measurement was conducted in Gabon to assess virological failure (VF) defined by a VL result ≥1000 copies/ml and DRMs among adult patients living with non-B HIV-1 strains and receiving first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based antiretroviral therapy for at least 12 months. Risk factors associated with VF and DRMs were assessed.
  
  
  RESULTS
  Between March 2010 and March 2011, a total of 375 patients were consecutively enrolled from two decentralized (one semirural and one rural) HIV care centres. Median time on ART was 33.6 months (range, 12-107). Overall, the rate of VF was 41.3% (36.4-46.4). Among viremic patients, 56.7% (80/141) had at least one DRM and 37.6% had dual-class resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and NNRTIs. The most frequent DRMs were K103N/S (46.1%) and M184V/I (37.6%). Thymidine analogue mutations were found in 10.6%. Independent risk factors associated with VF were being followed up at the semirural centre (P=0.033), having experienced unstructured treatment interruptions (P=0.0044), and having low CD4+ counts at enrolment (P<0.0001). A longer time on ART (P=0.0008) and being followed up at the rural centre (P=0.021) were risk factors for DRMs.
  
  
  CONCLUSIONS
  This is the first study conducted in Gabon providing VF rates and DRM patterns in adult patients receiving first-line ART. In sub-Saharan Africa, where NNRTI-based regimens are recommended as the standard for first-line ART, strengthening virological monitoring together with preventing unplanned treatment interruptions are a global public health priority.
authors.affiliation: Laboratoire de Rétrovirologie, CIRMF, BP769, Franceville, Gabon.
authors.forename: Florian
authors.initials: F
authors.lastname: Liégeois
authors.forename: Caroline
authors.initials: C
authors.lastname: Vella
authors.forename: Sabrina
authors.initials: S
authors.lastname: Eymard-Duvernay
authors.forename: Jeanne
authors.initials: J
authors.lastname: Sica
authors.forename: Laurent
authors.initials: L
authors.lastname: Makosso
authors.forename: Augustin
authors.initials: A
authors.lastname: Mouinga-Ondémé
authors.forename: Arnaud Delis
authors.initials: AD
authors.lastname: Mongo
authors.forename: Vanina
authors.initials: V
authors.lastname: Boué
authors.forename: Christelle
authors.initials: C
authors.lastname: Butel
authors.forename: Martine
authors.initials: M
authors.lastname: Peeters
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Gonzalez
authors.forename: Eric
authors.initials: E
authors.lastname: Delaporte
authors.forename: François
authors.initials: F
authors.lastname: Rouet
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003430:Cross-Sectional Studies; D024882:Drug Resistance, Viral; D005260:Female; D005681:Gabon / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012307:Risk Factors; D012424:Rural Population
chemical_list: D019380:Anti-HIV Agents