OnabotulinumtoxinA dose-ranging study for hyperdynamic perioral lines.

BACKGROUND Few dosing data on onabotulinumtoxinA to treat hyperdynamic perioral lines (POLs) are available. Studying onabotulinumtoxinA in controlled settings is beneficial to treating a hyperfunctional orbicularis oris. OBJECTIVE To compare the dose-response relationship of two doses of onabotulinumtoxinA in hyperdynamic POLs. METHODS Female subjects (N = 60) received injections of onabotulinumtoxinA at four sites totaling 7.5 U or 12.0 U. Subjects returned at weeks 2, 4, 8, 12, 16, and 20. POL severity and total lip satisfaction (TLS) were assessed at all visits. RESULTS Investigator-assessed POL severity was reduced through week 20 for 12.0 U (p < .01). POL reduction for 7.5 U persisted until week 16 (p < .05). Responder rates did not differ until week 12 (12.0 U, 77%; 7.5 U, 36%; p = .003). Subject-assessed TLS was improved (p < .05) at all time points for both groups except at week 20 (12.0 U; p = .06). Most adverse events (AEs) were mild to moderate in severity and typical for onabotulinumtoxinA treatment in the lips, and the incidence was dose-dependent. CONCLUSION OnabotulinumtoxinA provides significant reductions in POL severity and high levels of subject satisfaction. Lack of dose response and fewer AEs suggest that treatment of hyperdynamic POLs with 7.5 U appears adequate for up to 16 weeks.