Effectiveness and safety of blonanserin monotherapy for first-episode schizophrenia with and without prominent negative symptoms: A prospective study

BACKGROUND Blonanserin, a novel antipsychotic, has demonstrated efficacy in treating both positive and negative symptoms. However, limited research exists on its dose-dependent effectiveness and safety in patients with and without prominent negative symptoms (PNS). AIM To evaluate the effectiveness and safety of blonanserin monotherapy for first-episode schizophrenia in real-world clinical settings and to explore the efficacy and safety of different doses of blonanserin for patients with PNS and without PNS. METHODS A 12-week, multicenter, prospective post-marketing surveillance was conducted. In this study, we included patients with first-episode schizophrenia who received blonanserin monotherapy. Patients were divided into those with PNS and without PNS, based on the Brief Psychiatric Rating Scale (BPRS) negative symptoms subscale scores. Additionally, patients were labeled as high-dose and low-dose groups according to the maximum daily dose they received. Effectiveness was assessed using the BPRS, and safety was evaluated through the incidence of adverse drug reactions (ADRs). RESULTS A total of 653 patients were included in the analysis, with 613 completing the study. The BPRS total score decreased significantly from 47.94 ± 16.31 at baseline to 26.88 ± 9.47 at 12 weeks (P < 0.001). A significant interaction of PNS × dose × time was observed for BPRS total scores (F = 3.47, P = 0.040) and negative symptom subscale scores (F = 6.76, P = 0.002). In the PNS group, the high-dose group showed greater reductions in BPRS total scores (P = 0.001) and negative symptom subscale scores (P = 0.003) than the low-dose group in week 12. In the without PNS group, no significant difference was observed between the high-dose and low-dose groups at any visit. Most adverse reactions were mild or moderate, with extrapyramidal symptoms (9.3%) being most common; 1.5% of patients gained ≥ 7% body weight at 12 weeks. CONCLUSION Blonanserin effectively alleviated the clinical symptoms of first-episode schizophrenia with an acceptable safety profile. High-dose blonanserin is particularly beneficial for patients with PNS in the acute phase of first-episode schizophrenia. However, due to the limitation of ADR reporting the real world, the ADR incidence observed in this study may be underestimated.