A 45-year-old woman with schizoaffective disorder requires an antipsychotic change due to inadequate symptom control on her current medication. Her baseline ECG shows a QTc interval of 470 ms. She also takes methadone 80 mg daily for opioid use disorder. The PMHNP needs to select an antipsychotic with the lowest risk of further QTc prolongation. Which of the following is the most appropriate choice?