Results of a Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of a Botulinum Toxin Type A Topical Gel for the Treatment of Moderate-to-Severe Lateral Canthal Lines
January 2012 | Volume 11 | Issue 1 | Original Article | 38 | Copyright © January 2012
Richard Glogau MD,a,b Andrew Blitzer MD DDS,c Fredric Brandt MD,d Michael Kane MD,e Gary D. Monheit MD,f Jacob M. Waugh MDG
aUniversity of California San Francisco, CA bPrivate Practice, San Francisco, CA cHead & Neck Surgical Group, New York, NY dDermatology Research Institute, LLC, Coral Gables, FL eManhattan Eye, Ear & Throat Institute, New York, New York fTotal Skin & Beauty Dermatology Center, Birmingham, AL gRevance Therapeutics, Inc., Newark, CA
Abstract
Background: Injections of botulinum toxin type A are commonly used to treat facial wrinkles; however, undesirable effects are associated with injections (e.g., pain, bruising, ptosis, immunogenicity, and needle aversion). To address these issues, RT001 Botulinum Toxin Type A Topical Gel is being developed for the treatment of lateral canthal lines.
Objectives: To assess the safety and efficacy of RT001 for the treatment of lateral canthal lines in a randomized, double-blind, placebo-controlled study.
Materials & Methods: Adult subjects were enrolled to receive a single treatment of RT001 (n=45) or placebo (n=45) applied topically in the lateral canthal area. The primary endpoint was the composite of the Investigator Global Assessment of Lateral Canthal Line Severity (IGA-LCL) and the Patient Severity Assessment of lateral canthal line severity (PSA) defined as a 2-point or greater improvement on both scales.
Results: At four weeks, 44.4 percent of subjects treated with RT001 achieved a 2-point or greater improvement on a rigorous composite of both the IGA-LCL and PSA scales compared to 0.0% for the placebo subjects (P<0.0001). At four weeks, 88.9 percent of subjects achieved clinically relevant improvement by investigator assessment. Adverse events were mild in severity and unrelated to study treatment.
Conclusions: RT001 appears to be a safe and well-tolerated treatment for improvement of lateral canthal lines.
J Drugs Dermatol. 2012;11(1):38-45.
INTRODUCTION
substantial body of literature supports the safe and effective use of botulinum toxin type A (BoNTA)
injections for temporary improvement of facial wrinkles. Although an off-label use, BoNTA treatment of lateral canthal lines (LCL), also known as periorbital rhytids or crow's
feet, has become a common clinical practice. Clinical practice has evolved substantially since the initial use of BoNTA for treatment of LCL. Current treatment recommendations
focus on preserving a natural voluntary smile while softening the wrinkles in a neutral facial position ("at rest").1-2 This goal has been accomplished through
progressive declines in the amount of BoNTA injected as well as broad use of intradermal injections.1-6 LCL at rest have been shown to be the major factor in
perception of facial age and a 20 percent improvement in these LCL has been shown to be both readily detected and clinically significant.7 Elimination of the LCL
which are normally present during a smile has come to be recognized as aesthetically unappealing. Lack of LCL at smile is perceived as a posed photo-smile, or a fake smile;
these smiles are cortical in origin, voluntary, and do not reflect genuine emotion.1,4-6,8-9 The appearance of a photo smile is perceived to be an insincere smile
which does not communicate genuine happiness, and a BoNTA-induced insincere smile has been shown to actually decrease subjects' ability to experience certain positive
emotions.4-6,8-9 Even when
