OnabotulinumtoxinA for Platysma Prominence: Safety and Efficacy Results from a Phase 3 Open-Label Repeat Treatment Study.

Abstract

OnabotulinumtoxinA (onabotA) treatment of prominent platysma muscles demonstrates a safety profile consistent with other onabotA aesthetic indications and effectively improves the appearance of vertical neck bands and jawline definition. To evaluate the safety and efficacy of repeat onabotA treatment for improving the appearance of moderate-to-severe platysma prominence. Participants received up to 4 onabotA treatments administered ≥3 months apart, including treatment with onabotA or placebo in the double-blind lead-in study. All treatment-emergent adverse events (TEAEs) related to study treatment were mild in severity with no observed trends across treatment cycles. Four participants reported 6 adverse events (AEs) of special interest, including dysphagia (4 events) and facial paresis (2 events). All were mild in severity with no evidence of distant spread of toxin; almost all resolved by study end and none resulted in discontinuation. The percentages of participants achieving a ≥1-grade improvement at maximum contraction as assessed by clinicians on Day 14 for each treatment cycle were 83.6%, 92.0%, 90.0%, and 98.0% and by participants were 82.5%, 90.4%, 87.0%, and 94.0%. Repeat onabotA treatment is well-tolerated and improves platysma prominence over the course of multiple treatment cycles.