2022 / Randomized, double-blind, placebo-controlled phase III
Why the definition of “responder” matters.
What changes when both patient and investigator must agree?
Source access: publication abstract
The study#
- Design
- Randomized, double-blind, placebo-controlled phase III
- Population
- 355 participants with glabellar lines
- Follow-up / endpoint
- Week 4 primary response
- Source
- Aesthetic Surgery Journal, 2022 · PMID 35092418
What the authors found#
Composite response was 64.7% with letibotulinumtoxinA and 0% with placebo. Investigator-only and participant-only rates were higher.[1]
Editorial interpretation
Why it is interesting#
Requiring both ratings and at least two-grade improvement creates a stricter endpoint.
Compare endpoint definitions before comparing percentages.
What it cannot tell us#
- Not an active-comparator trial.
- Different scales and responder definitions prevent simple comparison with another toxin trial.
Selection for this library reflects educational interest. It is not a systematic search, formal certainty grade, or complete account of the literature.
Funding & commercial context#
Consult the publication's full text for funding and conflict-of-interest statements; the abstract does not provide a complete disclosure.
Continue with the product
Source & citation#
Mueller et al. — letibotulinumtoxinA phase III trial ↗Checked 2026-09-06 · Aesthetic Surgery Journal, 2022 · PMID 35092418. Cite the original publication when discussing its results; this page is an interpretation.
Aesthetic Pass. Why the definition of “responder” matters. Product Atlas research interpretation 2026.09.06.1. https://aestheticpass.com/products/studies/letybo-composite-response/