A Study to Assess the Safety and Efficacy of AGN-151586 Injections for the Treatment of Moderate to Severe Forehead Lines (FHL) in Adult Participants

Inclusion Criteria: * Participant must have moderate (Grade 2) or severe (Grade 3) forehead lines (FHL) at maximum eyebrow elevation as assessed by the subject and investigator using Forehead Lines Severity Scale (FHLSS) at Screening visit and Baseline Day 1 visit. * Participant must have moderate (Grade 2) or severe (Grade 3) glabellar lines (GL) at maximum frown as assessed by the subject and investigator using Allergan Glabellar Lines Severity Scale (AGLSS) at Screening visit and Baseline Day 1 visit. * Sufficient visual acuity without the use of eyeglasses (contact lens use is acceptable) to accurately assess their FHL and GL in investigator's opinion. Exclusion Criteria: * Clinically relevant or significant ECG abnormalities. * Active infection or dermatological condition at any of the treatment injection sites.