According to a new study, Botox is still the best product for correcting upper-face wrinkles — but not by much — when compared with the new kid on the botulinum block.
Two Florida plastic surgeons have completed a study comparing the newest FDA-approved botulinum toxin type A product, incobotulinumtoxinA (Xeomin, Merz) with longtime leader onabotulinumtoxinA (Botox, Allergan) on performance in correcting upper-face wrinkles.
According to the authors — Ruth Hill Yeilding, M.D., Winter Park, and John P. Fezza, M.D., Sarasota — this is the first prospective, split-face, randomized, double-blind study to address three types of facial wrinkles — glabellar lines, crow’s feet and forehead lines — using a 1:1-dose ratio.
The study enrolled 45 subjects, 41 of whom were women. Ages ranged from 26 to 82. A three-judge independent review panel compared photographs of patients with the upper-face validated assessment scales and selected a grade ranging from 0 (no lines) to 4 (very severe) for each side of the face before treatment and 3 days, 2 weeks, 3 months and 4 months after treatment. For toxin comparison, the researchers calculated differences in the degree of wrinkle scale at each period compared with pre-treatment and performed statistical analyses. They analyzed wrinkle types both individually and combined.
In the randomization, onabotulinumtoxinA was used on the right side of 22 patient faces and on the left side in the remaining 23. The contralateral side was given incobotulinumtoxinA. Glabella dosage was 20 units, consistent with FDA guidelines for both toxins. Since there were no FDA guidelines for forehead lines or crow’s feet at the time of the study’s design, the authors used 10 and 15 units, respectively, based on their experience, prior studies and peer discussion.
“For identical dosage, both onabotulinumtoxinA and incobotulinumtoxinA are safe and effective in the treatment of glabellar lines, crow’s feet lines and forehead lines,” the authors write. “However, for our dosage levels, onabotulinumtoxinA was statistically greater in combined dynamic wrinkle reduction at 3 days, 2 weeks, 3 months and 4 months.”
Dr. Yeilding tells Cosmetic Surgery Times that dosage was the determining factor.
“Our choice of study dosage levels was on the low side, at 50 units for three areas, and therefore reduced the influence of product saturation,” she says. “We believe this contributes to being able to see differences between products. This is the first split-face study showing statistically significant difference in efficacy between neuromodulators.”
The study appears in the May issue of Plastic and Reconstructive Surgery.