title: Factors associated with viral rebound among highly treatment-experienced HIV-positive patients who have achieved viral suppression.
abstract: OBJECTIVE
  More and more highly treatment-experienced patients are achieving viral suppression. However, the durability of suppression remains unclear.
  
  
  METHODS
  Patients from Royal Free Hospital (London, UK) and JW Goethe University Hospital (Frankfurt, Germany) who had failed > or = 1 antiretroviral (ARV) regimen in all three main drug classes and > or = 3 previous ARV regimens and subsequently achieved viral load < 50 HIV-1 RNA copies/mL were included. They were followed until stopping pre-combination antiretroviral therapy, end of follow-up or viral rebound (two viral loads >400 copies/mL).
  
  
  RESULTS
  Two hundred and forty-seven patients contributed 723 person-years and 114 viral rebounds [rate=15.8 per 100 person-years; 95% confidence interval (CI) 12.9-18.7]. More recent calendar years of viral suppression [relative risk (RR)=0.90 per year later; 95% CI 0.81-1.00; P=0.05] and greater number of ARVs in the regimen not previously failed (RR=0.78 per 1 ARV more; 95% CI 0.65-0.95; P=0.01) were associated with lower viral rebound rates. At 0-1, 1-2, 2-3 and > 3 years after achieving suppression, the rebound rates were 30.9, 9.2, 4.3 and 3.5 per 100 person-years, respectively. Compared to 0-1 years, the adjusted RRs (95% CIs) after 1-2, 2-3 and > 3 years were 0.33 (0.18-0.58), 0.21 (0.09-0.48) and 0.14 (0.06-0.33), respectively (P<0.0001).
  
  
  CONCLUSIONS
  Although rebound rates are high, especially in the first year after viral suppression, this risk reduces substantially if highly treatment-experienced patients can maintain viral suppression.
authors.affiliation: Research Department of Infection and Population Health, Royal Free and University College Medical School, London, UK. c.smith@pcps.ucl.ac.uk
authors.forename: C J
authors.initials: CJ
authors.lastname: Smith
authors.forename: A N
authors.initials: AN
authors.lastname: Phillips
authors.forename: B
authors.initials: B
authors.lastname: Dauer
authors.forename: M A
authors.initials: MA
authors.lastname: Johnson
authors.forename: F C
authors.initials: FC
authors.lastname: Lampe
authors.forename: M S
authors.initials: MS
authors.lastname: Youle
authors.forename: M
authors.initials: M
authors.lastname: Tyrer
authors.forename: S
authors.initials: S
authors.lastname: Staszewski
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D004334:Drug Administration Schedule; D005260:Female; D005858:Germany; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1; D006801:Humans; D008131:London; D008297:Male; D012008:Recurrence; D013997:Time Factors; D017211:Treatment Failure; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents