title: Preservation of anemia control and weekly ESA dosage after conversion from PEG-Epoetin beta to darbepoetin alfa in adult hemodialysis patients: the TRANSFORM study.
abstract: BACKGROUND
  There is scant real-world information on switching treatment for anemia associated with chronic kidney disease (CKD) from methoxy polyethylene glycol-epoetin beta (PEG-Epo) to darbepoetin alfa (DA). TRANSFORM was a multi-center, observational study designed to describe the time course of hemoglobin (Hb) concentration (primary outcome measure) and other parameters of clinical management of anemia in European hemodialysis patients in clinical practice before and after a switch from PEG-Epo to DA.
  
  
  METHODS
  Eligible subjects were adult patients with CKD dialyzed at European dialysis centers for ≥26 weeks and treated with PEG-Epo for ≥14 weeks immediately prior to being switched to DA and no earlier than January 2011. Erythropoiesis-stimulating agent doses and Hb values were recorded for the 14-week pre-switch and 26-week post-switch periods.
  
  
  RESULTS
  Of the 1,027 eligible patients enrolled at 42 hemodialysis centers in 7 European countries, 785 were included in analyses. Mean (95% confidence interval [CI]) Hb was generally stable: 11.19 (11.11, 11.26), 11.48 (11.40, 11.57), and 11.29 (11.20, 11.37) g/dL at month -1 pre-switch and months 3 and 6 post-switch, respectively. The geometric mean (95% CI) PEG-Epo dose at month -1 was 27.4 (26.0, 28.8) µg/week; DA dose was 29.4 (27.9, 30.9), 23.3 (21.9, 24.9), and 25.6 (24.1, 27.1) µg/week at months 1, 4, and 6, respectively. The geometric mean (95% CI) dose ratio at switching was 1.06 (1.01, 1.11). When stratifying by dose-ratio categories <0.8, 0.8-1.2, and >1.2 at switching, mean DA dose and Hb converged within narrow ranges by month 6 post-switch: 23.9-27.0 µg/week and 11.1-11.5 g/dL, respectively. Hb excursions <10 g/dL were less frequent post-switch versus pre-switch.
  
  
  CONCLUSIONS
  Mean Hb values remained within a narrow range following switching from PEG-Epo to DA in this population of hemodialysis patients. Time trends of mean Hb and DA dose indicate that physicians titrated DA doses post-switch, to attain Hb concentrations comparable to those attained pre-switch with PEG-Epo.
authors.affiliation: Algemeen Ziekenhuis Sint Lucas, Groenebriel 1, 9000, Ghent, Belgium, jan.donck@azstlucas.be.
authors.forename: Jan
authors.initials: J
authors.lastname: Donck
authors.forename: Lourdes
authors.initials: L
authors.lastname: Gonzalez-Tabares
authors.forename: Jacques
authors.initials: J
authors.lastname: Chanliau
authors.forename: Heike
authors.initials: H
authors.lastname: Martin
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Stamatelou
authors.forename: Nick
authors.initials: N
authors.lastname: Manamley
authors.forename: Mourad
authors.initials: M
authors.lastname: Farouk
authors.forename: Janet
authors.initials: J
authors.lastname: Addison
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D000068256:Darbepoetin alfa / Q000008:administration & dosage*; D057915:Drug Substitution / Q000379:methods / Q000706:statistics & numerical data; D004921:Erythropoietin / Q000008:administration & dosage*; D005060:Europe / Q000453:epidemiology; D005260:Female; D006397:Hematinics / Q000008:administration & dosage / Q000627:therapeutic use; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D006435:Renal Dialysis / Q000379:methods; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000453:epidemiology / Q000628:therapy
chemical_list: D006397:Hematinics; D006454:Hemoglobins; C508420:continuous erythropoietin receptor activator; D004921:Erythropoietin; D000068256:Darbepoetin alfa; D011092:Polyethylene Glycols