title: Standard-dose versus low-dose azathioprine in the treatment of Crohn's disease: A prospective randomized study.
abstract: OBJECTIVE
  Azathioprine (AZA) is widely used to treat Crohn's disease (CD) with a recommended dose of 2-2.5 mg/kg per day for Westerners. Asian patients are suggested to take a lower dose. However, many clinicians reported poor efficacy with a reduced dose. This study aimed to explore a efficient and safe dose of AZA providing the best efficacy for Chinese CD patients.
  
  
  METHODS
  Fifty patients with active CD were enrolled and randomized into two groups (n = 25 each). All other treatments were the same except that group A received 1 mg/kg per day and group B took 2 mg/kg per day of AZA. Complete remission (CR) rate and response rate at weeks 12, 24 and 48 were assessed by using intent-to-treat (ITT) and per-protocol (PP) analyses. Adverse events and recurrence rate were also evaluated.
  
  
  RESULTS
  At week 48, CR rate and response rate in group B (ITT: 50.0% and 59.1%; PP: 57.9% and 68.4%) were significantly higher than those in group A (ITT: 13.0% and 17.4%; PP: 16.7% and 22.2%) (P < 0.05). Nine adverse events occurred, including pancreatitis (n = 1), arthritis (n = 2) and myelosuppression (n = 6). There was no significant difference in adverse events between the two groups. However, recurrence rate was significantly higher in group A than in group B (P = 0.042).
  
  
  CONCLUSIONS
  AZA 2 mg/kg per day is more appropriate than 1 mg/kg per day for Chinese CD patients with a high efficacy, a low recurrence rate and not increased adverse events.
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of General Practice, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Jing Jing
authors.initials: JJ
authors.lastname: Xia
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Xiao
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Ling Na
authors.initials: LN
authors.lastname: Ye
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Xiao Lin
authors.initials: XL
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Zi Wen
authors.initials: ZW
authors.lastname: Lin
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Zhen Jie
authors.initials: ZJ
authors.lastname: Xu
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Yi Biao
authors.initials: YB
authors.lastname: Huang
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Meng Yu
authors.initials: MY
authors.lastname: Wang
authors.affiliation: Department of Gastroenterology, Peking Union Medical College Hospital, Beijing, China.
authors.forename: Jia Ming
authors.initials: JM
authors.lastname: Qian
authors.affiliation: Department of Gastroenterology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China.
authors.forename: Pin Jin
authors.initials: PJ
authors.lastname: Hu
authors.affiliation: Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang Province, China.|Inflammatory Bowel Disease Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Qian
authors.identifier: http://orcid.org/0000-0002-1732-8817
authors.initials: Q
authors.lastname: Cao
mesh_terms: D001379:Azathioprine / Q000008:administration & dosage*; D003424:Crohn Disease / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D007166:Immunosuppressive Agents; D001379:Azathioprine
keywords: Crohn's disease; adverse event; azathioprine; dose; efficacy