The objective of this study was to evaluate the efficacy and safety of botulinum toxin type A for the treatment of glabellar lines. Patients with moderate or severe glabellar lines at maximal frown received intramuscular injections of placebo or 20 U of botulinum toxin type A (Botox; Allergan, Inc., Irvine, Calif.) distributed among five injection sites (one in the procerus muscle and two in each corrugator supercilii). Follow-up assessments were performed at 7, 30, 60, 90, and 120 days after injections. Efficacy measures were the physician’s rating of glabellar line severity at maximal frown and at rest (none, mild, moderate, or severe) and the patient’s global assessment of changes in glabellar lines, from +4 (100 percent better) to −4 (100 percent worse). A total of 273 patients were enrolled (botulinum toxin, 202 patients; placebo, 71 patients). All except five patients (botulinum toxin, two patients; placebo, three patients) completed the study. For the physician’s rating at maximal frown, the responder rate (percentage of patients with severity ratings of none or mild in follow-up evaluations) for the botulinum toxin group peaked at 77 percent at day 30 and was significantly greater than that for the placebo group at every follow-up visit (p < 0.001). For the patient’s assessment, the responder rate (percentage of patients with scores of +2 or more) for the botulinum toxin group peaked at 89 percent at day 30 and was significantly greater than that for the placebo group at every follow-up visit (p < 0.001). Rates of adverse events were similar for the two groups. The only adverse event with an incidence of ≥5 percent was headache (botulinum toxin, 11 percent; placebo, 20 percent). The incidence of blepharoptosis was 1 percent for the botulinum toxin group. Botulinum toxin type A was remarkably safe and effective in reducing glabellar lines.
Vancouver, British Columbia, Canada; Santa Monica, Los Angeles, and Irvine, Calif.; and Dallas, Texas
From the Department of Ophthalmology, University of British Columbia; Clinical Research Specialists and Department of Dermatology, University of California, Los Angeles, School of Medicine; Division of Dermatology, Baylor University Medical Center; and Allergan, Inc.
Received for publication December 7, 2001;
revised April 15, 2003.
Nina Eadie, M.B.A.
2525 Dupont Drive
Irvine, Calif. 92612-1599
Presented at the Ninth Congress of the European Academy of Dermatology and Venereology, in Geneva, Switzerland, October of 2000, and at the Annual Meeting of the American Academy of Dermatology, in Washington, D.C., March of 2001.