Botulinum Type A Toxin in the Treatment of Lateral Canthal Lines (Crow's Feet)

• The following outcomes measures were all assessed at weeks 2, 4, 8, 12, 16, 20 & 24:
• - change in severity of lateral canthal lines at maximum smile at all assessment time points compared to the baseline visit, as assessed by the investigator and an independent panel (photographically)
• - change in severity of lateral canthal lines at rest at all assessment time points compared to the baseline visit, as assessed by an independent panel (photographically) and the investigator
• - change in the patient's assessment of satisfaction with the appearance of their lateral canthal lines at all assessment time points compared to the baseline visit
• - change in the patient's assessment of satisfaction with their general appearance at all assessment time points compared to the baseline visit
• - Safety will be determined by the collection of adverse event data throughout the study

Despite the wealth of information in the literature regarding the cosmetic applications of botulinum type A toxin (BoNT-A), and the widespread use of the BoNT-A for cosmetic applications, the number of randomised, controlled clinical trials is small. Much of the published information is based on open-label studies or anecdotal data. Of the robust trial data that is available, the vast majority relates to the treatment of glabellar lines, and there is little data available regarding the use of BoNT-A in lateral canthal lines. This study aims to determine the optimum dose for the use of BoNT-A in this area.

Inclusion Criteria:

• Male or female patients, 18 to 65 years of age.
• In the opinion of the Investigator moderate to severe lateral canthal lines (crow’s feet) during maximum smile on both sides of the face.
• In the opinion of the Investigator mild to severe lateral canthal lines (crow’s feet) at rest on both sides of the face.

Exclusion Criteria:

• Any prior surgery affecting the orbicularis oculi muscle, prior blepharoplasty or brow lift, or any prior cosmetic procedures or scars that may interfere with the evaluation of the study results.
• Previous insertion of any non-absorbable material in the periorbital region or facial treatment with augmentation material within 12 months prior to screening.
• Any prior treatment with botulinum toxin (of any serotype).
• Previous treatment with lasers for skin resurfacing or treatment with deep chemical peels within 12 months prior to screening.
• Inability to substantially lessen the lateral canthal lines by physically spreading them apart.
• Facial conditions that could affect safety or efficacy results such as: active infection or other skin problem in the periorbital area (e.g. acute acne lesions or ulcers); history of facial nerve palsy; marked facial asymmetry; ptosis; excessive dermatochalasis; deep dermal scarring; thick sebaceous skin; photodamage etc.