title: Approval summary: azacitidine for treatment of myelodysplastic syndrome subtypes.
abstract: OBJECTIVE
  This article summarizes data submitted to the U.S. Food and Drug Administration for marketing approval of azacitidine as injectable suspension (Vidaza, Pharmion Corporation, Boulder, CO) for treatment of patients with myelodysplastic syndrome.
  
  
  METHODS
  In one phase 3 controlled trial, 191 study subjects were randomized to treatment with azacitidine or to observation; an additional 120 patients were treated with azacitidine in two phase 2 single arm studies. The primary efficacy end point was the overall response rate, defined as complete or partial normalization of peripheral blood counts and bone marrow blast percentages for at least 4 weeks.
  
  
  RESULTS
  In the controlled trial, the overall response rate was 15.7% in the azacitidine treatment group; there were no responders in the observation group (P < 0.0001). Response rates were similar in the two single arm studies. During response patients stopped being red cell or platelet transfusion dependent. Median duration of responses was at least 9 months. An additional 19% of azacitidine-treated patients had less than partial responses, most becoming transfusion independent. The most common adverse events attributed to azacitidine were gastrointestinal, hematologic, local (injection site), and constitutional. There were no azacitidine-related deaths.
  
  
  CONCLUSIONS
  On May 19, 2004 the U.S. Food and Drug Administration approved azacitidine as injectable suspension for treatment of patients with the following myelodysplastic syndrome subtypes: refractory anemia or refractory anemia with ringed sideroblasts (if accompanied by neutropenia or thrombocytopenia or requiring transfusions), refractory anemia with excess blasts, refractory anemia with excess blasts in transformation, and chronic myelomonocytic leukemia. Full prescribing information is available at http://www.fda.gov/cder/foi/label/2004/050794lbl.pdf. Azacitidine is the first agent approved for treatment of myelodysplastic syndrome.
authors.affiliation: Division of Oncology Drug Products, Center for Drug Evaluation and Research, Food and Drug Administration, Rockville, Maryland, USA. edvardas.kaminskas@fda.hhs.gov
authors.forename: Edvardas
authors.initials: E
authors.lastname: Kaminskas
authors.forename: Ann
authors.initials: A
authors.lastname: Farrell
authors.forename: Sophia
authors.initials: S
authors.lastname: Abraham
authors.forename: Amy
authors.initials: A
authors.lastname: Baird
authors.forename: Li-Shan
authors.initials: LS
authors.lastname: Hsieh
authors.forename: Shwu-Luan
authors.initials: SL
authors.lastname: Lee
authors.forename: John K
authors.initials: JK
authors.lastname: Leighton
authors.forename: Hasmukh
authors.initials: H
authors.lastname: Patel
authors.forename: Atiqur
authors.initials: A
authors.lastname: Rahman
authors.forename: Rajeshwara
authors.initials: R
authors.lastname: Sridhara
authors.forename: Yong-Cheng
authors.initials: YC
authors.lastname: Wang
authors.forename: Richard
authors.initials: R
authors.lastname: Pazdur
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001374:Azacitidine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D017277:Drug Approval; D006801:Humans; D007279:Injections, Subcutaneous; D009190:Myelodysplastic Syndromes / Q000188:drug therapy*; D016896:Treatment Outcome; D014481:United States; D014486:United States Food and Drug Administration
chemical_list: D000964:Antimetabolites, Antineoplastic; D001374:Azacitidine