A 12-week study to investigate how the body handles alogabat once it is swallowed, how safe it is, and whether it could be effective in treating the symptoms of AS

A Study to Investigate the Pharmacokinetics (PK) and Safety and to Provide Proof of Mechanism of Alogabat in Children and Adolescents Aged 5-17 Years With Angelman Syndrome (AS) With Deletion Genotype.