A Study to Evaluate Sequential Administration of AGN-151586 and OnabotulinumtoxinA (BOTOX) Injections in Adult Participants for Treatment of Glabellar Lines

Facial lines that develop from repeated facial expression, such as glabellar lines (GL), are typically treated by selectively weakening specific muscles with small quantities of botulinum toxin. The purpose of this study is to assess how safe and effective sequential administration of AGN-151586 and OnabotulinumtoxinA (BOTOX) is in adult participants with moderate to severe GL. AGN-151586 is an investigational product being developed for the treatment of GL. Participants are placed in 1 of 2 groups, called treatment arms. Each group receives a different treatment. One group will receive AGN-151586 followed by BOTOX and the other group will receive placebo followed by BOTOX. There is a 1 in 2 chance that participants will be assigned to placebo. Around 80 adult participants with moderate to severe GL will be enrolled in the study in approximately 10 sites around the United States. Participants will receive either AGN-151586 or Placebo administered as 5 intramuscular injections to the glabellar complex on Day 1. Eligible participants may then receive BOTOX injections on Day 30 and will be followed for up to 4 months. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, checking for side effects and completing questionnaires.