Study To Evaluate The Efficacy And Safety Of Balovaptan In Adults With Post-Traumatic Stress Disorder (PTSD)

Inclusion Criteria: * Participants who have a current diagnosis of PTSD as per DSM-5 criteria, with a score of \>/=33 on the PCL-5 at screening * The index trauma event must have occurred in adulthood, i.e., when the participant was \>/=18 years old * The index trauma event must have occurred at least 6 months prior to screening and no more than 10 years prior to screening * At baseline, either taking a stable dose of a single antidepressant (SSRI or SNRI) for management of PTSD and have been on that medication for \>/=6 weeks at that stable dosage and demonstrating residual symptoms of PTSD or prior demonstrated lack of tolerability or lack of efficacy and not taking an antidepressant medication at baseline for \>/=6 weeks * Treatment with permitted medications and/or non-pharmacological interventions at a stable dose for 6 weeks prior to screening * For women of childbearing potential: agreement to remain abstinent or use contraception Exclusion Criteria: * Participants who are experiencing ongoing exposure to traumatic events within 3 months of screening * Participants who are pregnant or breastfeeding, or intending to become pregnant during the study or within 14 days after the final dose of study drug * Clinically significant psychiatric and/or neurological conditions, which may interfere with the assessment of safety or efficacy endpoints * Substance use disorders during last 12 months * Significant risk for suicidal behaviour * Epilepsy or seizure disorder considered not well controlled within the past 6 months or changes in anticonvulsive therapy within the last 6 months * Clinical diagnosis of peripheral neuropathy * Within the last 2 years, unstable or clinically significant cardiovascular disorders * Positive serology results for hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibody, or human immunodeficiency virus (HIV) 1 or 2 * Moderate or severe hepatic or renal impairment * History of coagulopathies, bleeding disorders, blood dyscrasias, hematological malignancies, myelosuppression (including iatrogenic) * Medical history of malignancy, if not considered cured * Participants who have received treatment with investigational therapy within 8 weeks prior to randomization * Known hypersensitivity to balovaptan, its components, or any of the excipients used in the formulation