title: Continued azacitidine therapy beyond time of first response improves quality of response in patients with higher-risk myelodysplastic syndromes.
abstract: BACKGROUND
  In the AZA-001 trial, azacitidine (75 mg/m(2) /d subcutaneously for Days 1-7 of every 28-day cycle) demonstrated improved survival compared with conventional care regimens in patients with International Prognostic Scoring System-defined intermediate-2- or high-risk myelodysplastic syndrome and World Health Organization-defined acute myeloid leukemia with 20% to 30% bone marrow blasts.
  
  
  METHODS
  This secondary analysis of the AZA-001 phase 3 study evaluated the time to first response and the potential benefit of continued azacitidine treatment beyond first response in responders.
  
  
  RESULTS
  Overall, 91 of 179 patients achieved a response to azacitidine; responding patients received a median of 14 treatment cycles (range, 2-30). Median time to first response was 2 cycles (range, 1-16). Although 91% of first responses occurred by 6 cycles, continued azacitidine improved response category in 48% of patients. Best response was achieved by 92% of responders by 12 cycles. Median time from first response to best response was 3.5 cycles (95% confidence interval [CI], 3.0-6.0) in 30 patients who ultimately achieved a complete response, and 3.0 cycles (95% CI, 1.0-3.0) in 21 patients who achieved a partial response.
  
  
  CONCLUSIONS
  Continued azacitidine therapy in responders was associated with a quantitative increase in response to a higher response category in 48% of patients, and therefore may enhance clinical benefit in patients with higher-risk MDS.
authors.affiliation: Department of Medicine - Oncology, Mount Sinai School of Medicine, New York, NY 10029, USA. lewis.silverman@mssm.edu
authors.forename: Lewis R
authors.initials: LR
authors.lastname: Silverman
authors.forename: Pierre
authors.initials: P
authors.lastname: Fenaux
authors.forename: Ghulam J
authors.initials: GJ
authors.lastname: Mufti
authors.forename: Valeria
authors.initials: V
authors.lastname: Santini
authors.forename: Eva
authors.initials: E
authors.lastname: Hellström-Lindberg
authors.forename: Norbert
authors.initials: N
authors.lastname: Gattermann
authors.forename: Guillermo
authors.initials: G
authors.lastname: Sanz
authors.forename: Alan F
authors.initials: AF
authors.lastname: List
authors.forename: Steven D
authors.initials: SD
authors.lastname: Gore
authors.forename: John F
authors.initials: JF
authors.lastname: Seymour
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D001374:Azacitidine / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000188:drug therapy*; D012306:Risk; D013997:Time Factors
chemical_list: D000964:Antimetabolites, Antineoplastic; D001374:Azacitidine