A 38-year-old male with opioid use disorder has been stable on buprenorphine/naloxone 16 mg/4 mg daily for 6 months. He now presents with persistent depressive disorder with worsening anhedonia, insomnia, fatigue, and difficulty concentrating that has not improved despite sustained recovery. His PHQ-9 score is 17. He has no prior psychiatric medication trials. His current medications include buprenorphine/naloxone and a daily multivitamin. He denies suicidal ideation. The PMHNP is planning pharmacologic treatment for his depression. Which treatment plan is most appropriate?