Can brexpiprazole be switched safely in patients with schizophrenia and dopamine supersensitivity psychosis? A retrospective analysis in a real-world clinical practice.

BACKGROUND: Several studies have reported that a switch to the dopamine partial agonist (DPA) aripiprazole (ARP), especially when the switch is abrupt, is likely to fail and sometimes worsen psychosis in schizophrenia patients already under high-dose antipsychotic treatment. Such a switching failure is speculated to be related to be the dopamine supersensitivity state. The risks of switching to the DPA brexpiprazole (BREX) have not been reported. AIMS AND METHODS: We retrospectively analyzed the cases of 106 patients with schizophrenia to identify any factors related to the success or failure of switching to BREX. RESULTS: The comparison between the patients with dopamine supersensitivity psychosis (n = 44) and those without (n = 62) revealed no significant difference in the switching failure judged at the sixth week. A comparison of the patients with successful switching (n = 80) and those who failed (n = 26) revealed that patients with treatment-resistant schizophrenia (TRS) were significantly more likely to fail. A logistic regression analysis also revealed that patients with past failure of switching to ARP are likely to succeed in switching to BREX. The 2-year follow-up of the patients with successful switching to BREX suggested that the patients who were treated with BREX, even temporarily, experienced some improvement in their Global Assessment of Functioning and Clinical Global Impression-Severity scores. CONCLUSIONS: Overall, the results indicate that patients with schizophrenia can be switched more safely to BREX compared to ARP. However, the failure of switching to BREX could be higher in patients with TRS, and thus, starting BREX treatment in refractory patients warrants careful monitoring.

Successful rechallenge with paliperidone after clozapine treatment for a patient with dopamine supersensitivity psychosis.

We describe the case of a 49-year-old Japanese male patient successfully treated with a paliperidone rechallenge following 2-year treatment with clozapine for treatment-resistant schizophrenia. He had responded well to conventional antipsychotic treatment for the initial psychotic episode but gradually developed dopamine supersensitivity; even treatment with paliperidone and another antipsychotic medication (a total up to 1700 mg in chlorpromazine-equivalent dose) had not improved his psychotic symptoms. Clozapine treatment produced temporary symptomatic relief, but the clozapine dose could not be increased to > 150 mg due to the patient's intolerance. Following low-dose clozapine treatment for 2 years, a rechallenge with paliperidone monotherapy ameliorated his psychotic symptoms. This suggests that clozapine may have the potential to release the dopamine supersensitivity state. Our patient's case indicates that for patients with dopamine supersensitivity psychosis, a rechallenge with a previously ineffective antipsychotic after clozapine treatment may be successful.

Milnacipran treatment and potential biomarkers in depressed patients following an initial SSRI treatment failure: a prospective, open-label, 24-week study.

BACKGROUND: We assessed the effect of switching patients with major depressive disorder to milnacipran following an initial selective serotonin reuptake inhibitor treatment failure, and explored potential biomarkers in their blood. METHODS: We conducted a prospective, open-label, 24-week trial. Depression was assessed with the 17-item Hamilton Depression Rating Scale. Patients showing a ≥50% reduction in Hamilton Depression Rating Scale scores from baseline to final visit were considered responders. Regarding adverse effects (AEs), moderate-to-severe AEs were specifically identified as effects that required any medical treatment or that induced treatment withdrawals. We also measured blood levels of various molecules including inflammatory cytokines. RESULTS: Of the 30 participants who enrolled, 17 completed this study. The responder rate was 30% (n=10). Baseline serum levels of interleukin-6 (Z=-2.155; P=0.031) and interleukin-8 (Z=-2.616; P=0.009) were significantly higher when moderate-to-severe AEs were present (n=13 patients with moderate-to-severe AEs). Serum levels of macrophage inflammatory protein-1ß showed a significant continuous decrease from the baseline level (Friedman's test: χ (2)=23.9, df=4, P<0.001) only in non-responders. CONCLUSION: These results demonstrate that serum levels of interleukin-6, interleukin-8, and macrophage inflammatory protein-1ß as potential blood biomarkers could be utilized to identify the responsiveness of patients to serotonin and norepinephrine reuptake inhibitor like milnacipran, or to identify those patients who may experience AEs strong enough to warrant discontinuation of treatment.