Resumen

Objectives: Using a Phase II, multicenter, randomized, double-blind, active-controlled study design, to investigate both the safety of a single treatment of 40U of the injectable neuromodulator, prabotulinumtoxinA-xvfs (administered as 5 injections, 0.05 mL (8U) per injection), and its duration of effect in providing temporary improvement in the appearance of moderate to severe glabellar lines in adult subjects, as measured at maximum frown on the 4-point Glabellar Line Scale (GLS: 0=none, 1=mild, 2=moderate, 3=severe). Introduction: Since first introduced over 20 years ago, injectable botulinum toxins (type A) have become the standard of care for the temporary improvement in the appearance of moderate to severe glabellar lines. However, at approved doses, a maximum effect is typically achieved within 30 days; the duration of effect then wanes over the next 3-4 months. Not surprisingly, there has been considerable interest in investigating higher doses of these toxins as a means to increase their duration of effect. In 2019, prabotulinumtoxinA Materials / method: 154 adults with moderate to severe glabellar lines were randomized 1:1:1 to a single treatment of either 40U prabotulinumtoxinA-xvfs (PRA 40), 20U prabotulinumtoxinA-xvfs (PRA 20) or 20U onabotulinumtoxinA (ONA 20), where each 20U dose was administered as 5 injections, 0.1 mL (4U) per injection. Safety and effectiveness outcomes were assessed up until the subject had returned to their baseline GLS score. The primary endpoint was the duration of effect, defined as the number of days from Treatment Day to the day that GLS severity at maximum frown by Investigator assessment returned to Baseline. Results: No serious, severe or unexpected adverse events were reported. No seroconversions were evident with the 40U dose. The median number of days from Treatment Day to the day that GLS severity at maximum frown returned to Baseline was 183, 149 and 148 days for each of the PRA 40, PRA 20 and ONA 20 groups, respectively. The difference in the durations of effect between PRA 40 and PRA 20, derived by comparing the two Kaplan-Meier survival curves, was statistically significant: adjusted hazard ratio of 1.892; p=0.0109. The adjusted hazard ratio between PRA 40 and ONA 20 was 2.38; p=0.0002. Conclusion: A doubled-dose 40U hyper-concentrated formulation of prabotulinumtoxinA-xvfs was safe and effective for the treatment of moderate to severe glabellar lines in adult subjects, with a median duration of effect of 6 months