title: A series of three sequential, randomized, controlled studies of repeated treatments with botulinum toxin type A for migraine prophylaxis.
abstract: We examined the effects of multiple treatments with low doses of botulinum toxin type A (BoNTA; BOTOX(R), Allergan Inc., Irvine, CA) versus placebo for prophylaxis of episodic migraine. This was a series of 3 sequential, randomized, controlled studies of 418 patients with a history of 4 to 8 moderate to severe migraines per month. In study I, patients were randomized to treatment with placebo or BoNTA (7.5 U, 25 U, or 50 U) in predetermined fixed injection sites on the front and sides of the head only. In study II, patients continued to receive, or were randomized to, 2 consecutive treatments with 25 U or 50 U. In study III, patients were randomized to placebo or continuation of 25 U or 50 U. Injection cycles were each 4 months long. BoNTA and placebo produced comparable decreases from baseline in the frequency of migraines at each time point examined (P >or= .201). No consistent, statistically significant differences were observed for any efficacy variable. Adverse events were similar among the groups within each study. In these exploratory studies of episodic migraine patients, repeated injections of low doses of BoNTA into fixed frontal, temporal, and glabellar sites were not more effective than placebo. BoNTA was safe and well tolerated.
  
  
  CONCLUSIONS
  Beneficial effects of BoNTA in the treatment of migraine have been reported, but positive results are not universal, possibly because the optimal patient population and regimen are not yet definitively established. This study explores the effects of multiple injections of low BoNTA doses into fixed sites for episodic migraine.
authors.affiliation: Elkind Headache Center, Mount Vernon, New York, USA.
authors.forename: Arthur H
authors.initials: AH
authors.lastname: Elkind
authors.forename: Philip
authors.initials: P
authors.lastname: O'Carroll
authors.forename: Andrew
authors.initials: A
authors.lastname: Blumenfeld
authors.forename: Ronald
authors.initials: R
authors.lastname: DeGryse
authors.forename: Rozalina
authors.initials: R
authors.lastname: Dimitrova
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001763:Blepharoptosis / Q000139:chemically induced; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage* / Q000009:adverse effects; D002908:Chronic Disease / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D004333:Drug Administration Routes; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000188:drug therapy* / Q000503:physiopathology / Q000517:prevention & control*; D009465:Neuromuscular Agents / Q000008:administration & dosage* / Q000009:adverse effects; D017060:Patient Satisfaction / Q000706:statistics & numerical data; D015990:Placebo Effect; D011788:Quality of Life; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A