title: Poor early virologic performance and durability of abacavir-based first-line regimens for HIV-infected children.
abstract: BACKGROUND
  Concerns about stavudine (d4T) toxicity have led to increased use of abacavir (ABC) in first-line pediatric antiretroviral treatment (ART) regimens. Field experience with ABC in ART-naïve children is limited.
  
  
  METHODS
  Deidentified demographic, clinical and laboratory data on HIV-infected children initiating ART between 2004 and 2011 in a large pediatric HIV treatment program in Johannesburg, South Africa, were used to compare viral suppression at 6 and 12 months by initial treatment regimen, time to suppression (<400 copies/mL) and rebound (>1000 copies/mL after initial suppression). Adjusted logistic regression was used to investigate confounders and calendar effects.
  
  
  RESULTS
  Two thousand thirty-six children initiated either d4T/3TC- or ABC/3TC-based first-line regimens in combination with either boosted lopinavir (LPV/r) or efavirenz (EFV). 1634 received d4T regimens (LPV/r n = 672; EFV n = 962) and 402 ABC regimens (LPV/r n = 192; EFV n = 210). At 6 and 12 months on ART, viral suppression rate was poorer in ABC versus d4T groups within both the LPV/r and EFV groups (P < 0.0001 for all points). In ABC groups, time to suppression was significantly slower (log-rank P < 0.0001 and P = 0.0092 for LPV/r- and EFV-based, respectively) and time to rebound after suppression significantly faster (log-rank P = 0.014 and P = 0.0001 for LPV/r- and EFV-based, respectively). Logistic regression confirmed the worse outcomes in the ABC groups even after adjustment for confounders.
  
  
  CONCLUSIONS
  Data from this urban pediatric ART service program show significantly poorer virological performance of ABC compared with d4T-based regimens, a signal that urgently warrants further investigation.
authors.affiliation: Empilweni Services and Research Unit, Department of Paediatrics & Child Health, Rahima Moosa Mother and Child Hospital, Coronationville, Johannesburg, Gauteng, South Africa. karltechnau@gmail.com
authors.forename: Karl-Günter
authors.initials: KG
authors.lastname: Technau
authors.forename: Erica
authors.initials: E
authors.lastname: Lazarus
authors.forename: Louise
authors.initials: L
authors.lastname: Kuhn
authors.forename: Elaine J
authors.initials: EJ
authors.lastname: Abrams
authors.forename: Gillian
authors.initials: G
authors.lastname: Sorour
authors.forename: Renate
authors.initials: R
authors.lastname: Strehlau
authors.forename: Gary
authors.initials: G
authors.lastname: Reubenson
authors.forename: Mary-Ann
authors.initials: MA
authors.lastname: Davies
authors.forename: Ashraf
authors.initials: A
authors.lastname: Coovadia
mesh_terms: D019380:Anti-HIV Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D015224:Dideoxynucleosides / Q000627:therapeutic use*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology*; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D016896:Treatment Outcome; D019562:Viral Load; D000099227:Abacavir
chemical_list: D019380:Anti-HIV Agents; D015224:Dideoxynucleosides; D000099227:Abacavir