title: Comparison of two formulations of botulinum toxin type A for the treatment of glabellar lines: a double-blind, randomized study.
abstract: BACKGROUND
  Different formulations of botulinum toxin type A can behave differently. There has been little clinical research directly comparing formulations.
  
  
  OBJECTIVE
  We sought to compare the efficacy and tolerability of two botulinum toxin type A formulations-BoNTA1 and BoNTA2-in the treatment of moderate and severe glabellar lines.
  
  
  METHODS
  Sixty-two patients with moderate or severe glabellar lines at maximum contraction were randomly assigned to receive 20 U of BoNTA1 or 50 U of BoNTA2 (20% in the procerus muscle, 80% in the corrugator muscles).
  
  
  RESULTS
  The incidence of 1-grade improvement or greater in glabellar line severity at maximum contraction was as follows: 77% (BoNTA1) versus 59% (BoNTA2) at week 12, 53% versus 28% at week 16. The estimated incidence of relapse was 23% (BoNTA1) versus 40% (BoNTA2) at week 16. Both formulations were similarly well tolerated.
  
  
  CONCLUSIONS
  Few male and non-Caucasian subjects were studied.
  
  
  CONCLUSIONS
  BoNTA(1) offered more prolonged efficacy than BoNTA2 in the treatment of glabellar lines at the dose ratio of 2.5:1 (BoNTA2:BoNTA1) used in this study.
authors.affiliation: Cranley Clinic, London, United Kingdom.
authors.forename: Philippa
authors.initials: P
authors.lastname: Lowe
authors.forename: Rickie
authors.initials: R
authors.lastname: Patnaik
authors.forename: Nicholas
authors.initials: N
authors.lastname: Lowe
mesh_terms: D000328:Adult; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage* / Q000627:therapeutic use; D002626:Chemistry, Pharmaceutical; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005152:Facial Muscles; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D017060:Patient Satisfaction; D012008:Recurrence; D015595:Skin Aging / Q000187:drug effects*; D013997:Time Factors; D016896:Treatment Outcome; D044465:White People
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A