Is Cold Storage Still a Must? Evaluating Room-Temperature OnabotulinumtoxinA for Glabellar Lines Treatment.

[BACKGROUND] New botulinum toxin type A (BoNT-A) formulations eliminated cold-chain storage before reconstitution. Nonetheless, concerns remain about BoNT-A properties when stored at room temperature after reconstitution.

[AIM] This study aimed to evaluate the sterility and effectiveness of BoNT-A storage at room temperature in glabellar wrinkles.

[METHODS] BoNT-A (Allergan Botox, Brazil) was reconstituted and maintained in a stove at 37°C for 60 days and then tested for sterility according to the Pharmacopeia guidelines. Then, sixty patients aged 25-60 years were divided into two groups: Group 1 (G1) received BoNT-A immediately after reconstitution, and Group 2 (G2) received BoNT-A after 7 days at room temperature. Participants were assessed for wrinkle severity using the Merz Scale, satisfaction with treatment using the Face-Q scale, and muscle activity by electromyography. Data were collected before injections and after 15, 30, 60, and 90 days.

[RESULTS] Absence of turbidity evidenced no microbial growth in all periods analyzed. Both groups showed significant reductions in glabellar contraction (p < 0.001), wrinkle severity (p < 0.05), and improved satisfaction. G1 presented lower wrinkle severity, while G2 reported higher satisfaction (p < 0.05).

[CONCLUSION] Room temperature and longer storage periods may not affect OnabotulinumtoxinA sterility and clinical results.