This disclosure relates to gastro-resistant, controlled release dosage forms comprising Compound (I): or a pharmaceutically acceptable salt and/or solvate thereof, the pharmacokinetic properties of these dosage forms, and the preparation of the same. The novel dosage forms disclosed herein are useful in reducing the risk of QT prolongation in a subject and in treating a disorder in a subject in need thereof, e.g., a subject diagnosed with schizophrenia, for example, in treating the negative symptoms in a subject diagnosed with schizophrenia having the CYP2D6 EM genotype.本發明係有關一種耐胃性控制釋放劑型,其包含化合物(I):或其醫藥上可接受之鹽與/或溶劑合物、此等劑型之藥物動力學性質、及其製法。本文所揭示該新穎劑型適用於個體降低QT延長之風險,及於有需要之個體(例如,經診斷罹患思覺失調症之個體)治療疾患,例如,於帶有CYP2D6 EM基因型之經診斷罹患思覺失調症之個體治療負性症狀。