OnabotulinumtoxinA versus PrabotulinumtoxinA-xvfs: A Randomized, Triple-blind, Split-face Study on the Time to Onset, Rhytid Appearance, and Patient Satisfaction in Forehead and Glabellar Lines.

Background: Both onabotulinumtoxinA and prabotulinumtoxinA-xvfs are FDA-approved formulations of botulinum toxin A for the treatment of glabella and forehead rhytids. Objective: We sought to compare the onset to action and patient satisfaction of onabotulinumtoxinA and prabotulinumtoxinA-xvfs in treating dynamic rhytids of the forehead and glabella. Methods: Fifteen patients, aged 28 to 74, were enrolled and completed the study. Patients were randomly assigned to receive equal amounts of onabotulinumtoxinA and prabotulinumtoxinA-xvfs injected to opposite sides of the face in the glabella and forehead at Day 0 by a blinded injector. Glabellar and frontalis muscle onset to action and rhytid appearance were blindly evaluated using photographs at Days 0, 2, 4, 6, 8, 10 post-injection. Patients rated their satisfaction of left and right sides using a standardized scale. Results: There was no statistically significant difference in onset to action, rhytid appearance, and patient satisfaction after injection with onabotulinumtoxinA versus prabotulinumtoxinA-xvfs in the corrugator and frontalis muscles. Although not statistically significant, a trend existed towards increased patient satisfaction with onabotulinumtoxinA. Conclusion: Both onabotulinumtoxinA and prabotulinumtoxinA-xvfs are equally efficacious formulations of botulinum toxin type A for the treatment of glabellar and forehead rhytids.