The present disclosure describes compositions and methods for treating at least one negative symptom in a human subject who does not have a clinical diagnosis of schizophrenia. The compositions and methods employ a therapeutically effective amount of a compound of formula (I), or a pharmaceutically acceptable salt, hydrate, solvate or polymorph thereof本揭示內容用來治療不具有思覺失調症之臨床診斷的人類受試者之至少一種負性症狀的組成物及方法。該組成物及方法採用治療有效量的式(I)化合物，或其藥學上可接受的鹽、水合物、溶劑合物或同素異形體
