Network intervention analysis indicates that roluperidone achieves its effect on negative symptoms of schizophrenia by targeting avolition.

Roluperidone, a 5-HT2A, sigma2, and ɑ1A-adrenergic receptor antagonist, has proven efficacious for treating negative symptoms of schizophrenia in phase 2b and phase 3 clinical trials. Using network analysis, we demonstrated that the improvements observed in the phase 2b trial resulted from targeting avolition which was highly central and spurred a cascading effect of global negative symptom reductions when successfully treated. The current study aims to replicate these network findings using the phase 3 roluperidone clinical trial data. Participants included 496 schizophrenia patients with moderate to severe negative symptoms who were randomized to either roluperidone 32 mg/day (n =167), 64 mg/day (n = 162), or placebo (n = 167). Negative symptoms were assessed at baseline and weeks 2,4,8, and 12. Network intervention analysis (NIA) evaluated treatment-induced symptom changes over time to identify direct and indirect treatment effects. This analytic approach extends prior work by determining whether the symptoms with highest centrality have causal effects on the entire negative symptom construct and directly lead to symptom improvement. NIA indicated that the efficacious 64 mg/day dose of roluperidone had a direct effect on avolition, suggesting that changes in avolition propels treatment effects across the entire negative symptom constellation. These phase 3 findings replicated the phase 2b findings, indicating that from a network perspective, roluperidone achieves its effect by influencing the extent to which avolition drives other negative symptoms. These findings are relevant for understanding negative symptoms and how to treat them in neuropsychiatric disorders.

Prevalence of prominent and predominant negative symptoms across different criteria for negative symptom severity and minimal positive symptoms: A comparison of different criteria.

Negative symptoms are a source of disability in schizophrenia, but criteria for identifying patients for clinical trials are in flux. Minimum severity for negative symptoms is paired with a definition of minimal psychosis to identify predominant negative symptoms. Two previous successful negative symptoms treatment studies used very different severity and selection criteria. We compared the prevalence of participants meeting those two criteria in a large outpatient sample of participants with schizophrenia. Data from 867 outpatients with schizophrenia who participated in one of four NIMH-funded studies were analyzed. Common data elements included diagnoses, the PANSS, and an assessment of everyday functioning. We compared previous criterion for premoninant negative symptoms based on low levels of agitation and psychosis and different cut-offs for negative symptoms severity. 57 % of the participants met the agitation-based criteria for low scores and 33 % met the psychosis-based criteria. 18 % met total PANSS score ≥ 20 and 8 % met ≥24 prominent negative symptoms criteria. 14 % met low agitation and PANSS≥20 and 2 % met the low psychosis and negative symptoms ≥24 criteria. Participants who met all predominant criteria had more impairments in social functioning (all p < .001, all d > 0.37). Criteria for predominant negative symptoms from previous clinical trials identify widely different numbers of cases, with criteria for negative symptom severity and low symptoms both impacting. All criteria yield the expected profile of relatively specific social deficits. Even in unselected populations who participated in complex research protocols, 14 % meet low- agitation based criteria for predominant negative symptoms and many more participants would be expected to meet criteria with enrichment for the presence of negative symptoms.