Study: Patient-Reported Effectiveness of OnabotulinumtoxinA for Lateral Canthal Lines

Can onabotulinumtoxinA (Botox; Allergan, an AbbVie Company) treatment for crow’s feet lines (CFL) impact how patients feel about themselves? A study conducted by Yan Wu, MD, PhD, of Peking University First Hospital in Beijing, China and colleagues revealed that patients experienced significant improvements in their psychological well-being and appearance after onabotulinumtoxinA up through day 150.¹

CFL, also known as lateral canthal lines, are a hallmark of aging and often cause emotional distress, Wu and colleagues said. Researchers cited a recent study that found Asian American women rate CFL as the worst aging symptom and their highest priority for treatment.² OnabotulinumtoxinA is approved for use in 55 countries. The authors said that while there are many studies examining the clinical efficacy and safety of this treatment, much can be learned from studies on patients’ self-perceived satisfaction in appearance, as well as emotional and psychological impacts. “In real-world practice, subject satisfaction drives successful results and repeat treatments,” the authors wrote. “Therefore, patient-reported outcomes (PROs) have become a foundation for the clinical study of facial aesthetic treatments.”

Study authors examined 417 Chinese adults who had moderate to severe CFL at their widest smiles by conducting a 5-month, randomized, double-blind, placebo-controlled phase 3 clinical study. Researchers said that study methods were previously published.3 In that study, authors conducted the phase 3 study from September 2014-June 2015 at 9 sites in China.

Chinese men and women greater than or equal to 18 years of age with bilateral moderate to severe CFL at their widest smiles were included in the study. The mean age of participants was 46.4 years, and 83% of subjects were women. CFL severity was assessed by both investigators and subjects using the Facial Wrinkle Scale with Asian Photonumeric Guide (FWS-A). Patients who were currently being treated with botulinum toxin, or who had been previously treated within the past year were excluded. Patients were also excluded from the study if they had hypersensitivity or known immunization to botulinum toxin; had any contraindicating medical condition; were pregnant; had previous surgery at the site of treatment; had eyelid or eyebrow ptosis; and/or had eyelid hooding or other skin laxity or eyelid hooding that was unlikely to benefit for treatment or would affect CFL assessment.

Patients received either placebo (101) or 24 units of onabotulinumtoxinA through 3 intramuscular 0.1-mL injections on each side (316). Wu and colleagues said the study end point was the proportion of patients whose CFL severity was reduced to mild or none at day 30 at maximum smile.

Patients reported their outcomes on the Facial Line Satisfaction Questionnaire (FLSQ) and the Facial Line Outcomes (FLO-11) questionnaire, both of which report patient satisfaction and the psychological impact of treating upper facial lines, according to the authors. The FLSQ has 9-item baseline questions that measure the patient’s expectations for treatment of CFL. This is followed up with an 11-item questionnaire measures how the patient feels about the treatment results.

“FLSQ Impact Domain items explore appearance-related psychological impacts of treatment,” investigators wrote. The FLO-11 questionnaire contains 11 items that measure the impact of CFL on patients’ appearance and sense of well-being and self-perception. It uses an 11-point scale from 0/not at all to 10/very muchto rate how a subject is feeling.

Statistical analysis used Wilcoxon rank-sum test for between-group comparisons. “Distributions of FLO-11 and FLSQ results were summarized by treatment group, with baseline item results summarized by treatment group for the [modified intent-to-treat] population,” investigators reported, continuing that baseline/baseline change analyses for FLO-11 items were variance analysis based.1 Researchers used a range of 0 (worst) to 100 (best) to standardize and average FLSQ Impact Domain scores.¹

Wu and colleagues noted that these results are in line with other studies that have been conducted on Asian patients, including 2 studies on Japanese subjects.^4,5 Researchers also said that additional studies have shown that Asian subjects seem to achieve none to mild CFL results faster than non-Asian patients.^3,5 “Taken together, these factors may have contributed to the findings of the present study. It is also important for clinicians to be aware that the pattern of CFLs and facial skin or anatomy differ between Asian and non-Asian subjects,which may necessitate a customized injection pattern for Asian subjects.”^5,6,7

Wu and colleagues stressed that PRO are essential to completely assessing how effective treatment is from the patient perspective, in addition to provider opinion. They said this may also help providers select appropriate patients for CFL treatment. “Additionally, the PRO findings presented here provide evidence that supports a patient-centric approach to CFL treatment planning,” the study authors concluded.

Disclosures:

Garcia is an employee of AbbVie and may own stock in the company.

Baradaran was an employee of Allergan (prior to its acquisition by AbbVie) when the work was completed.

The other authors report no conflicts of interest.

References:
1. Wu Y, Li C, Garcia J, Baradaran S. Patient-reported outcomes in Chinese subjects treated with onabotulinumtoxinA for crow's feet lines. J Clin Aesthet Dermatol. 2021;14(10):27-31.

2. Chiu A, Hui A, Mariwalla K, et al. Understanding the Asian American facial aesthetic patient [poster]. Presented at: Annual Meeting of the Skin of Color Seminar Series; May 5–6, 2018; New York, NY.

3. Wu Y, Wang G, Li C, Mao C, Lei X, Lee E. Safety and efficacy of onabotulinumtoxinA for treatment of crow's feet lines in Chinese subjects. Plast Reconstr Surg Glob Open. 2019;7(1):e2079. Published 2019 Jan 22. doi:10.1097/GOX.0000000000002079

4. Kawashima M, Harii K, Horiuchi Y, et al. Safety, efficacy, and patient satisfaction with onabotulinumtoxinA for the treatment of upper facial lines in Japanese subjects. Dermatol Surg. 2020;46(4):483–490.

5. Harii K, Kawashima M, Furuyama N, et al. OnabotulinumtoxinA (Botox) in the treatment of crow’s feet lines in Japanese subjects. Aesthetic Plast Surg. 2017;41(5):1189–1197.

6. Park DH, Han DG, Shim JS, et al. Analysis of the patterns of lateral canthal rhytids and reference for botulinum toxin treatment in orientals. Aesthetic Plast Surg. 2012;36(5):1211–1215.

7. Kane MAC, Cox SE, Jones D, et al. Heterogeneity of crow’s feet lines patterns in clinical trial subjects. Dermatol Surg. 2015;41(4):447–456.