Methods of treating a seizure disorder with (1S,3S)-3-amino-4-(difluoromethylidene)cyclopentane-1-carboxylic acid, or (S)-3-amino-4-(difluoromethylenyl)cyclopent-1-ene-1-carboxylic acid (KT-II-115), or a pharmaceutically acceptable salt of any of the preceding, are provided. The methods provide therapeutic compositions that may be used to improve one or more symptoms of a seizure disorder. Methods of treating Prader-Willi syndrome with (1S,3S)-3-amino-4-(difluoromethylidene)cyclopentane-1-carboxylic acid, or (S)-3-amino-4-(difluoromethylenyl)cyclopent-1-ene-1-carboxylic acid (KT-II-115), or a pharmaceutically acceptable salt of any of the preceding, are provided. The methods provide therapeutic compositions that may be used to improve one or more symptoms of Prader-Willi syndrome.
