title: Effect of ketotifen premedication on adverse reactions during peanut oral immunotherapy.
abstract: BACKGROUND
  Oral immunotherapy (OIT) has shown promise in inducing desensitization for food allergy. However, there are safety concerns regarding the frequency and severity of adverse events during food OIT.
  
  
  OBJECTIVE
  To evaluate the effect of Ketotifen premedication on adverse reactions during peanut OIT.
  
  
  METHODS
  A randomized single blind placebo controlled pilot study was performed. Peanut OIT was performed using a previously published protocol. Ketotifen was up-titrated to 2 mg twice daily over two weeks (week -2 to 0), followed by a peanut OIT initial escalation day (day 1). Ketotifen was administered from week 0-4 of peanut OIT; reactions to peanut OIT doses were recorded by clinic staff and subject diary.
  
  
  RESULTS
  Six subjects (median age 10 years, peanut IgE >100kUA/L) were enrolled, 4 randomized to Ketotifen, 2 to placebo. The most common side effect of Ketotifen was fatigue (9% during up-titration). The rate of reaction per peanut OIT dose was lower for subjects on ketotifen (K) compared to placebo (P) during initial escalation on day 1 (K: 22% (8/36) vs. P: 67% (12/18)); week 0-4 build-up doses (K: 75% (3/4) vs. P: 100% (2/2)); and week 0-4 home doses (K: 50% (54/108) vs. P: 82% (27/33)). The rate of gastrointestinal symptoms per peanut OIT dose was also lower for subjects on ketotifen during initial escalation on day 1 (K: 17% (6/36) vs. P: 61% (11/18)); week 0-4 build-up doses (K: 75% (3/4) vs P: 100% (2/2)); and week 0-4 home doses (K: 46% (50/108) vs. P: 82% (27/33)).
  
  
  CONCLUSIONS
  Ketotifen premedication is well tolerated and reduces the rate of gastrointestinal symptoms during peanut OIT. These findings require confirmation in a larger study of Ketotifen premedication used throughout peanut OIT.
  
  
  BACKGROUND
  
  
  
  BACKGROUND
  NCT0162515.
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medicine, University of Toronto, 202 St Clair Ave W, Toronto, ON M4V 1R2, Canada.
authors.forename: Amanda
authors.initials: A
authors.lastname: Jagdis
authors.affiliation: Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Noam
authors.initials: N
authors.lastname: Berlin
authors.affiliation: Gordon Sussman Clinical Research Inc., Toronto, ON, Canada.
authors.forename: Carly
authors.initials: C
authors.lastname: Barron
authors.affiliation: Gordon Sussman Clinical Research Inc., Toronto, ON, Canada.
authors.forename: Mohana
authors.initials: M
authors.lastname: Giruparajah
authors.affiliation: Melbourne Medical School, University of Melbourne, Melbourne, Australia.
authors.forename: Nathan
authors.initials: N
authors.lastname: Leader
authors.affiliation: Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
authors.forename: Sean
authors.initials: S
authors.lastname: Maclachlan
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medicine, University of Toronto, 202 St Clair Ave W, Toronto, ON M4V 1R2, Canada.
authors.forename: Gordon L
authors.initials: GL
authors.lastname: Sussman
keywords: Adverse reactions; Antihistamine premedication; Desensitization; Ketotifen; Oral immunotherapy; Peanut allergy