Efficacy and Safety of OnabotulinumtoxinA for the Treatment of Platysma Prominence: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

[BACKGROUND] Platysma prominence (PP) is a common aesthetic concern associated with aging, leading to visible neck bands and loss of jawline definition. OnabotulinumtoxinA has emerged as a minimally invasive treatment; however, data from randomized controlled trials (RCTs) remain fragmented.

[AIMS] To systematically evaluate the efficacy and safety of onabotulinumtoxinA for treating moderate to severe PP through meta-analysis of RCTs.

[METHODS] PubMed, Cochrane CENTRAL, and ClinicalTrials.gov were searched from inception to March 2025 for RCTs comparing onabotulinumtoxinA with placebo in adults with PP. Two reviewers independently extracted data and assessed bias using the Cochrane RoB 2.0 tool. The primary outcomes were ≥ 1-grade and ≥ 2-grade improvement on the Clinician (C-APPS) and Participant (P-APPS) Allergan Platysma Prominence Scales. Secondary outcomes included patient satisfaction and treatment-emergent adverse events (TEAEs). Random-effects meta-analysis was used to estimate pooled risk ratios (RRs) with 95% confidence intervals (CIs).

[RESULTS] Three RCTs (n = 912) were included. OnabotulinumtoxinA significantly increased ≥ 1-grade (RR = 4.11; 95% CI, 3.60-4.69) and ≥ 2-grade (RR = 1.83; 95% CI, 1.54-2.17) improvements compared to placebo. Patient satisfaction was higher in the treatment group (RR = 5.55; 95% CI, 4.15-7.43). The incidence of TEAEs was similar between groups (RR = 0.95; 95% CI, 0.76-1.20), with most being mild and transient.

[CONCLUSIONS] OnabotulinumtoxinA is an effective and well-tolerated minimally invasive option for improving platysma prominence, offering significant aesthetic and patient-reported benefits without increasing adverse effects.