Prior Botulinum Toxin Treatment Does Not Impact Efficacy or Safety in Clinical Trials: Analysis of DaxibotulinumtoxinA for Injection in the SAKURA Program.

[BACKGROUND] Pivotal studies of approved botulinum toxin type A (BoNTA) formulations for treatment of glabellar lines have mostly included treatment-naive participants, and the impact of prior BoNTA treatment on efficacy and safety is not well documented.

[OBJECTIVE] To evaluate whether prior BoNTA treatment affects efficacy, duration of response, and tolerability for treatment of glabellar lines.

[METHODS] Adults with moderate or severe glabellar lines treated with DaxibotulinumtoxinA for Injection (DAXI) or placebo from the randomized, double-blind SAKURA 1/2 trials and the open-label SAKURA 3 safety study were analyzed by prior BoNTA treatment status. Efficacy was evaluated using investigator and participant assessments.

[RESULTS] In this analysis, 609 participants (52.2% BoNTA-experienced) from the SAKURA 1/2 trials and 2,380 (38.0% BoNTA-experienced) from the SAKURA 3 study were evaluated. Proportion of participants with none or mild glabellar lines and duration of response were similar between the BoNTA-naive and BoNTA-experienced cohorts in both the DAXI and placebo groups. The incidence of adverse events was also comparable regardless of prior BoNTA treatment status.

[CONCLUSION] Efficacy and tolerability were similar with DAXI and placebo regardless of prior BoNTA treatment. Assuming an appropriate washout is observed, future BoNTA trials should enroll both treatment-experienced and treatment-naive participants to reflect clinical practice.