Efficacy and Safety of Botulinum Toxin Type A for Treatment of Glabellar Lines: A Network Meta-Analysis of Randomized Controlled Trials

Background Botulinum toxin type A (BoNT/A) has been used in aesthetic applications worldwide, including glabellar lines. Currently, four BoNT/A preparations were approved for the improvement of moderate-to-severe glabellar lines: onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, and prabotulinumtoxinA. DaxibotulinumtoxinA is a new form of BoNT/A drug that is developed in clinical application. We performed this network meta-analysis (NMA) to assess the efficacy and safety of all these different BoNT/A formulations for treating glabellar lines. Methods The investigators searched randomized controlled trials (RCTs) using the Medical Subject Headings (MeSH) terms "botulinum toxin" and "glabellar lines." We searched the relevant studies in electronic databases as following: PubMed, Elsevier, EMBASE and the Cochrane Library. The end points included the percentage of subjects with a glabellar line severity (GLS) score of none (0) or mild (1), and the percentage of subjects achieving >= 1-point and 2-point improvement in glabellar line severity at maximum frown at approximately month 1 by the investigators' assessment. Results All formulations of BoNT/A were far superior to placebo in efficacy. DaxibotulinumtoxinA was the only treatment that significantly increased the proportion of subjects achieving >= 1 point improvement in GLS score compared with other BoNT/A formulations. Moreover, daxibotulinumtoxinA was ranked the highest for the proportion of subjects achieving >= 2-point improvement in GLS score. No significant differences were revealed for the incidence of any adverse events (AEs) that related to treatment or drug among all BoNT/A preparations. Conclusion The overall results of this NMA suggested that daxibotulinumtoxinA is a new BoNT/A preparation that may be not only more effective but also well-tolerated for the treatment of glabellar lines.