A Prospective, Non-Interventional, Single-Centre Study Assessing the Efficacy of a Holistic Upper Face Treatment With Botulinum Neurotoxin A

A Prospective, Non-interventional, Single-Centre Study Assessing the Efficacy of a Holistic Upper Face Treatment With Botulinum Neurotoxin A

The goal of this observational study is to learn about the safety, tolerability, and effectiveness of Letibotulinumtoxin A for the holistic treatment of the upper face in adults under 75 years old with moderate to severe upper facial lines, including glabellar lines, forehead lines, and lateral canthal lines.

The main questions it aims to answer are:

• Does Letibotulinumtoxin A safely and effectively reduce the severity of glabellar lines, forehead lines, and lateral canthal lines in adults under 75?
• How well is the treatment tolerated in everyday clinical practice?
• What is the patient satisfaction with holistic upper face treatment using Letibotulinumtoxin A?

Participants will:

• receive Letibotulinumtoxin A injections in the upper face, including glabellar lines, forehead lines, and lateral canthal lines.
• be observed and followed up to assess the severity of wrinkles, duration of effect, and patient satisfaction.
• report any adverse effects experienced during or after treatment.

Study Overview

• Status: Completed
• Conditions: Crow's Feet; Glabellar Lines; Forehead Lines; Canthal Lines
• Intervention / Treatment: Drug: Letybo®

• Study Type: Observational
• Enrollment (Actual): 20

Contacts and Locations

Study Locations

• Austria
  • Vienna
    • Vienna, Vienna, Austria, 1010
      • YUVELL

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Patients visiting the clinic for such a treatment as part of routine clinical practice.

Description

Inclusion Criteria:

• 18 years or older at time of treatment.
• At least mild frown lines at maximum frown, mild dynamic forehead lines at maximum eyebrow elevation or mild crow's feet at maximum smile.
• Subject has a stable medical condition with no uncontrolled systemic disease.
• Willingness to participate in the routine follow - up after 2 weeks and 4 months and a signed informed consent form.

Exclusion Criteria:

• Pregnancy and breast feeding.
• Neuromuscular disease (e.g. myasthenia gravis, Eaton - Lambert syndrome).
• Known impairment of blood coagulation.
• Drooping eyelid.
• Known allergy to botulinum toxin or human albumin (blood protein).
• Presence of acute infection or inflammation at the proposed injection sites.
• Botulinumtoxin treatment in the upper face within the last 16 weeks.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of subjects with a combined ≥ 1-point improvement in glabellar lines, forehead lines, and crow's feet severity at Week 2	Proportion of subjects achieving a combined responder status, defined as an improvement of at least 1 point from baseline in all 3 treated facial regions at Week 2, as assessed by the investigator using the following validated photo-numeric scales: Vertical glabellar lines assessed at maximum frowning using the Facial Wrinkle Scale (FWS), a scale ranging from 0 to 3, where higher scores indicate greater wrinkle severity.; Forehead lines assessed at maximum eyebrow elevation using the Croma Dynamic Forehead Line Assessment Scale (CDFLAS), a scale ranging from 1 to 5, where higher scores indicate greater wrinkle severity.; Crow's feet assessed at maximum smiling using the Croma Dynamic Crow's Feet Assessment Scale (CDCFAS), a scale ranging from 1 to 5, where higher scores indicate greater wrinkle severity. A subject is considered a responder only if the ≥ 1-point improvement criterion is met for all 3 scales simultaneously.	Week 2

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in vectorial skin displacement at maximum frowning assessed by three-dimensional (3D) surface imaging	Change from baseline in vectorial skin displacement at maximum frowning, measured at Week 2 and Week 16 using three-dimensional (3D) surface imaging technology. Vectorial skin displacement is quantified by comparing 3D facial surface images captured at baseline and follow-up visits to assess the magnitude and direction of skin movement during maximum frowning. Wrinkle severity at maximum frowning is additionally assessed by the investigator using the Facial Wrinkle Scale (FWS), a validated photo-numeric scale ranging from 0 to 3, where higher scores indicate greater wrinkle severity, to provide clinical context for the imaging-based measurements.	Week 2, Week 16
Change in vectorial skin displacement during maximum frontalis muscle contraction assessed by three-dimensional (3D) surface imaging	Change from baseline in vectorial skin displacement during maximum frontalis muscle contraction, assessed at Week 2 and Week 16 using three-dimensional (3D) surface imaging technology. Vectorial skin displacement is quantified by comparing 3D facial surface images obtained at baseline and follow-up visits to evaluate the magnitude and direction of skin movement over the forehead region during maximum frontalis muscle contraction. Forehead wrinkle severity during maximum contraction is additionally assessed by the investigator using the Croma Dynamic Forehead Line Assessment Scale (CDFLAS), a validated photo-numeric scale ranging from 1 to 5, where higher scores indicate greater wrinkle severity, to provide clinical context to the imaging-based measurements.	Week 2, Week 16
Change in vectorial skin displacement during maximum orbicularis oculi muscle contraction assessed by three-dimensional (3D) surface imaging	Change from baseline in vectorial skin displacement during maximum orbicularis oculi muscle contraction, assessed at Week 2 and Week 16 using three-dimensional (3D) surface imaging technology. Vectorial skin displacement is quantified by comparing 3D facial surface images captured at baseline and follow-up visits to evaluate the magnitude and direction of skin movement in the periocular (crow's feet) region during maximum orbicularis oculi muscle contraction. Wrinkle severity of the crow's feet during maximum contraction is additionally assessed by the investigator using the Croma Dynamic Crow's Feet Assessment Scale (CDCFAS), a validated photo-numeric scale ranging from 1 to 5, where higher scores indicate greater wrinkle severity, to provide clinical context for the imaging-based displacement measurements.	Week 2, Week 16
Percentage of subjects requiring a touch-up at Week 2	Percentage of subjects who, in the opinion of the investigator, required a touch-up treatment at the Week 2 visit to optimize the treatment outcome. The need for a touch-up is determined by the investigator based on clinical assessment.	Week 2
Patient satisfaction with treatment assessed using a clinic-internal patient satisfaction questionnaire	Patient satisfaction with the treatment as assessed by participants using the clinic-internal questionnaire titled "Patient Satisfaction Questionnaire". The questionnaire consists of 5 questions evaluating the participant's overall satisfaction with the treatment outcome. Each item is rated on a numeric ordinal scale from 1 to 5, where lower scores indicate higher patient satisfaction.	Week 16

Collaborators and Investigators

• Sponsor: Yuvell
• Collaborators: Croma-Pharma GmbH
• Investigators: Principal Investigator: Nikolaus Duschek, Priv.-Doz., PhD, YUVELL

Study record dates

Study Major Dates

• Study Start (Actual): January 29, 2024
• Primary Completion (Actual): May 16, 2024
• Study Completion (Actual): September 9, 2024

Study Registration Dates

• First Submitted: January 14, 2026
• First Submitted That Met QC Criteria: January 23, 2026
• First Posted (Actual): January 29, 2026

Study Record Updates

• Last Update Posted (Actual): January 29, 2026
• Last Update Submitted That Met QC Criteria: January 23, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: facial wrinkles; botulinum toxin A; glabellar lines; crow's feet; aesthetic medicine; forehead lines; canthal lines
• Additional Relevant MeSH Terms: Amino Acids, Peptides, and Proteins; Proteins; Biological Factors; Hydrolases; Enzymes; Enzymes and Coenzymes; Botulinum Toxins; Metalloendopeptidases; Endopeptidases; Peptide Hydrolases; Metalloproteases; Bacterial Proteins; Bacterial Toxins; Toxins, Biological; Botulinum Toxins, Type A; incobotulinumtoxinA
• Other Study ID Numbers: YUV-NIS-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No