A new clinical trial compared four botulinum toxin A formulations for treating glabellar lines, revealing measurable differences in onset and duration of effect in female patients aged 30 to 65. Abobotulinum toxin A and prabotulinum toxin A showed the fastest onset, while prabotulinum toxin A and incobotulinum toxin A showed sustained results at 6 months. The findings provide objective, comparative data on botulinum toxin A performance over time, helping guide individualized treatment choices based on patient goals.