A prospective rater- and subject-blinded study comparing the efficacy of incobotulinumtoxinA and onabotulinumtoxinA to treat crow's feet: a clinical crossover evaluation

Dermatol Surg. 2015 Jan:41 Suppl 1:S39-46. doi: 10.1097/DSS.0000000000000262.


Background: Botulinum toxin A products have been used in aesthetics for more than 20 years.

Objective: To compare incobotulinumtoxinA with onabotulinumtoxinA in the treatment of crow's feet.

Methods: This single-center, randomized, prospective, split-face, subject- and rater-blinded study with a clinical crossover evaluation comprised 2 consecutive treatment cycles, each of 3 months' duration separated by 6 months (i.e., a 9-month treatment interval). Fourteen subjects with symmetrical crow's feet were assessed using the Merz 5-point scale for crow's feet, after each treatment with incobotulinumtoxinA (right side of the face) and onabotulinumtoxinA (left side), or vice versa (1:1 dose conversion ratio). The treatment applied to each side of the face was reversed in Cycle 2.

Results: Crow's feet severity at rest and maximum contraction was improved to a similar extent by both treatments, in both cycles and on both sides of the face. Pooled data confirmed these results. Improvements were maintained at the final visit, 3 months after treatment (e.g., left side at maximum contraction-onabotulinumtoxinA mean score: 2.21 [baseline] vs 0.93 [1 month] vs 1.71 [3 months]; incobotulinumtoxinA mean score: 2.21 vs 0.86 vs 1.50).

Conclusion: IncobotulinumtoxinA and onabotulinumtoxinA (1:1 dose conversion ratio) were well tolerated, showing comparable efficacy and duration of treatment effect for crow's feet.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Botulinum Toxins, Type A / therapeutic use*
  • Cross-Over Studies
  • Eye
  • Female
  • Humans
  • Middle Aged
  • Neuromuscular Agents / therapeutic use*
  • Prospective Studies
  • Single-Blind Method
  • Skin Aging / drug effects*


  • Neuromuscular Agents
  • Botulinum Toxins, Type A
  • incobotulinumtoxinA