title: A randomized controlled clinical trial of topical insulin-like growth factor-1 therapy for sudden deafness refractory to systemic corticosteroid treatment.
abstract: BACKGROUND
  To date, no therapeutic option has been established for sudden deafness refractory to systemic corticosteroids. This study aimed to examine the efficacy and safety of topical insulin-like growth factor-1 (IGF-1) therapy in comparison to intratympanic corticosteroid therapy.
  
  
  METHODS
  We randomly assigned patients with sudden deafness refractory to systemic corticosteroids to receive either gelatin hydrogels impregnated with IGF-1 in the middle ear (62 patients) or four intratympanic injections with dexamethasone (Dex; 58 patients). The primary outcome was the proportion of patients showing hearing improvement (10 decibels or greater in pure-tone average hearing thresholds) 8 weeks after treatment. The secondary outcomes included the change in pure-tone average hearing thresholds over time and the incidence of adverse events.
  
  
  RESULTS
  In the IGF-1 group, 66.7% (95% confidence interval [CI], 52.9-78.6%) of the patients showed hearing improvement compared to 53.6% (95% CI, 39.7-67.0%) of the patients in the Dex group (P = 0.109). The difference in changes in pure-tone average hearing thresholds over time between the two treatments was statistically significant (P = 0.003). No serious adverse events were observed in either treatment group. Tympanic membrane perforation did not persist in any patient in the IGF-1 group, but did persist in 15.5% (95% CI, 7.3-27.4%) of the patients in the Dex group (P = 0.001).
  
  
  CONCLUSIONS
  The positive effect of topical IGF-1 application on hearing levels and its favorable safety profile suggest utility for topical IGF-1 therapy in patients with sudden deafness.
  
  
  BACKGROUND
  UMIN Clinical Trials Registry Number UMIN000004366, October 30th, 2010.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Graduate school of Medicine, Kyoto University, Kyoto 606-8507, Japan. tnakagawa@ent.kuhp.kyoto-u.ac.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Kozo
authors.initials: K
authors.lastname: Kumakawa
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Usami
authors.forename: Naohito
authors.initials: N
authors.lastname: Hato
authors.forename: Keiji
authors.initials: K
authors.lastname: Tabuchi
authors.forename: Mariko
authors.initials: M
authors.lastname: Takahashi
authors.forename: Keizo
authors.initials: K
authors.lastname: Fujiwara
authors.forename: Akira
authors.initials: A
authors.lastname: Sasaki
authors.forename: Shizuo
authors.initials: S
authors.lastname: Komune
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Harukazu
authors.initials: H
authors.lastname: Hiraumi
authors.forename: Norio
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Shiro
authors.initials: S
authors.lastname: Tanaka
authors.forename: Harue
authors.initials: H
authors.lastname: Tada
authors.forename: Michio
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yonezawa
authors.forename: Toshiko
authors.initials: T
authors.lastname: Ito-Ihara
authors.forename: Takafumi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Akira
authors.initials: A
authors.lastname: Shimizu
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
authors.forename: Juichi
authors.initials: J
authors.lastname: Ito
mesh_terms: D000279:Administration, Cutaneous; D003907:Dexamethasone / Q000008:administration & dosage; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D003639:Hearing Loss, Sudden / Q000188:drug therapy* / Q000503:physiopathology; D006320:Hearing Tests; D006801:Humans; D007270:Injections, Intra-Articular; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage*; D007564:Japan; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D014432:Tympanic Membrane
chemical_list: D005938:Glucocorticoids; D007334:Insulin-Like Growth Factor I; D003907:Dexamethasone