Efficacy and Safety of LetibotulinumtoxinA for the Treatment of Moderate-to-Severe Glabellar Lines: A Systematic Review and Meta-Analysis of RCTs.

[BACKGROUND] Botulinum toxin type A injections are widely used for the aesthetic treatment of glabellar lines; however, data on the efficacy and safety of newer formulations remain limited.

[AIM] This systematic review and meta-analysis aims to assess the efficacy and safety of the novel botulinum toxin LetibotulinumtoxinA-wlbg compared to placebo for treating moderate-to-severe glabellar lines.

[METHODS] A systematic literature search was conducted to identify randomized controlled trials (RCTs) comparing LetibotulinumtoxinA-wlbg with placebo in adults. A meta-analysis was performed using random-effects models, and the Cochrane RoB-2 tool was used to assess the risk of bias.

[RESULTS] Three RCTs including 1272 patients were analyzed. LetibotulinumtoxinA-wlbg was significantly more effective than placebo for the primary outcome, the composite responder rate at week 4 (risk ratio [RR] = 59.47; 95% CI: 14.95, 236.52). Sustained efficacy was observed at weeks 12 and 16, with significant improvements also seen in investigator-assessed, subject-assessed, and psychological outcomes. The safety analysis revealed no significant increase in the risk of serious, non-serious, or overall treatment-emergent adverse events.

[CONCLUSIONS] LetibotulinumtoxinA-wlbg is an efficacious and well-tolerated treatment for moderate-to-severe glabellar lines. The therapeutic effect is durable, with statistically significant efficacy maintained at 12 and 16 weeks post-treatment. Treatment results in a significant improvement in patients' psychological well-being related to their facial appearance. The safety profile is favorable, with no statistically significant increase in the risk of serious or non-serious adverse events compared to placebo. Further research, including direct head-to-head trials, is warranted to establish its comparative effectiveness.

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