title: Time to virological failure with atazanavir/ritonavir and lopinavir/ritonavir, with or without an H2-receptor blocker, not significantly different in HIV observational database study.
abstract: A retrospective electronic database study was conducted to determine any differences in time to virological failure and percent of virological failure among HIV-infected patients concurrently receiving H2-blockers versus patients not receiving these agents while receiving atazanavir (ATV)/ritonavir (r) or lopinavir (LPV)/r-containing antiretroviral treatment regimens. Data were culled from October 2003 (when ATV became commercially available) through February 2006. Virological failure was defined as (1) two plasma HIV-1 RNA levels >400 copies/mL after at least one HIV-1 RNA level below the level of detection or (2) failure to achieve an HIV-1 RNA <400 copies/mL within 24 weeks. Data from 267 ATV/r-treated patients who met the case definition were compared with data from 670 LPV/r-treated patients. Approximately 10% of the ATV/r group received concurrent H2-blockers when compared with 20% of the LPV/r group. Multivariate analysis showed no statistically significant differences regarding time to virological failure between or among the four subgroups, adjusting for differences in baseline characteristics (P = 0.79, log-rank test). At 750 days following treatment initiation, the proportion of patients not experiencing virological failure was 56% in the ATV/r-blocker subgroup, 48% in the ATV/r-alone subgroup, 45% in the LPV/r-alone subgroup and 42% in the LPV/r-blocker subgroup.
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Texas Southwestern Medical Center, Dallas, TX 75390-9113, USA. philip.keiser@utsouthwestern.edu
authors.forename: Philip H
authors.initials: PH
authors.lastname: Keiser
authors.forename: Naiel
authors.initials: N
authors.lastname: Nassar
mesh_terms: D019380:Anti-HIV Agents / Q000627:therapeutic use; D000069446:Atazanavir Sulfate; D016208:Databases, Factual; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D017320:HIV Protease Inhibitors / Q000627:therapeutic use; D015497:HIV-1 / Q000187:drug effects* / Q000502:physiology; D006635:Histamine H2 Antagonists / Q000627:therapeutic use; D006801:Humans; D061466:Lopinavir; D008297:Male; D008485:Medical Audit; D015999:Multivariate Analysis; D009842:Oligopeptides / Q000627:therapeutic use; D011725:Pyridines / Q000627:therapeutic use; D011744:Pyrimidinones / Q000627:therapeutic use; D012367:RNA, Viral / Q000097:blood; D019438:Ritonavir / Q000627:therapeutic use; D013997:Time Factors; D017211:Treatment Failure; D016896:Treatment Outcome; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D017320:HIV Protease Inhibitors; D006635:Histamine H2 Antagonists; D009842:Oligopeptides; D011725:Pyridines; D011744:Pyrimidinones; D012367:RNA, Viral; D061466:Lopinavir; D000069446:Atazanavir Sulfate; D019438:Ritonavir