Safety, Tolerability, and Pharmacokinetics of KarXT and Dual-burst Release of Xanomeline With Immediate-release Trospium Chloride in Adolescents With Psychiatric Disorders

Inclusion Criteria: * LAR (ie, legal guardian or caregiver) must have signed and dated an IRB/IEC-approved ICF in accordance with regulatory, local, and institutional guidelines. * Confirmed Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) psychiatric diagnosis of 1 of the following: 1. Schizophrenia or schizoaffective disorder 2. Bipolar I or II disorder 3. Attention-deficit/hyperactivity disorder (ADHD) 4. Tourette's disorder 5. Autism spectrum disorder (ASD) * Participant is judged by the investigator to be clinically stable (eg, no psychiatric hospitalization within the last 6 months; no imminent risk of suicide or injury to self, others, or property). Exclusion Criteria: * Any clinically significant neurological, metabolic (including type 1 diabetes), hepatic, renal, hematological, pulmonary, cardiovascular, GI (including active obstructive GI disorders), carcinoma, active biliary disorders (eg, symptomatic gallstones) and/or urological disorder, congestive heart failure (uncontrolled), or CNS infection that would pose a risk to the participants if they were to participate in the study or that might confound the results of the study. * Participant has a risk for suicidal behavior during the study, as determined by the investigator's clinical judgment and C-SSRS. * eGFR \< 60 mL/min. * History of Gilbert's Disease or history of liver disease (Child-Pugh class A and higher). * History or high risk of urinary retention, gastric retention, or narrow-angle glaucoma. * Participants with history of bladder stones or recurrent UTIs. * Other protocol defined inclusion/exclusion criteria apply.