A heterocyclic compound having a specific substituent or substituents is known as an active ingredient that has serotonin uptake inhibitory activity (or serotonin re-uptake inhibitory activity) in addition to dopamine D2 receptor partial agonistic activity (D2 receptor partial agonistic activity), serotonin 5-HT2A receptor antagonistic activity (5-HT2A receptor antagonistic activity), and adrenaline α1 receptor antagonistic activity (α1 receptor antagonistic activity) (Patent Literature (PTL) 1). This active ingredient has a wide therapeutic spectrum for central nervous system diseases (particularly schizophrenia).
In the pharmaceutical field, the development of pharmaceutical preparations that are suitable according to the severity of disease in various patients in need of treatment, patient predisposition, and other factors, has been desired. Although the heterocyclic compound disclosed in the above PTL 1 is known to have a wide therapeutic spectrum for neurological diseases, the development of a more effective therapeutic agent is currently desired.