To explore tolerability, safety and treatment response of flexibly dosed paliperidone palmitate (PP) in adult non-acute patients with schizophrenia previously unsuccessfully treated with the decanoate of haloperidol (Hal), flupentixol (Fpt), fluphenazine (Flu) or zuclopenthixol (Zuc).

International, prospective 6-month open-label study. Outcomes were clinical response (≥20% improvement in Positive and Negative Syndrome Scale (PANSS) total score), Personal and Social Performance scale (PSP), Extrapyramidal Symptom Rating Scale (ESRS) and treatment-emergent adverse events (TEAEs).

The intent-to-treat population comprised n=53 Hal, n=35 Fpt, n=44 Flu and n=42 Zuc patients. Mean age ranged from 42.1±10.7 [Zuc] to 44.4±9.4 years [Hal]), male gender from 57.1% [Zuc] to 69.8% [Hal]), and BMI from 27.3±5.9 [Hal] to 30.8±8.5 kg/m2 [Zuc]). Between 70.5% [Flu] and 85.7% [Fpt] of patients completed the study. Mean baseline PANSS total scores ranged from 73.7±14.1 [Fpt] to 75.7±13.2 [Hal]) and decreased significantly by -7.5±19.4 [Flu] to -10.6±21.5 points [Zuc] at endpoint (p<0.003 all subgroups). At endpoint, between 53.7% [Zuc] to 61.8% [Fpt] of patients had improved ≥20% in PANSS total score. Patient functioning (PSP) improved by 5.2±13.0 [Hal] to 6.4±15.2 points [Zuc] (all p≤0.0071). TEAEs reported at least once in all and in ≥5% in any subgroup were insomnia (max 11.5%), psychotic disorder (max 9.5%) and injection site pain (max 9.1% of subjects). Extrapyramidal symptoms in ESRS significantly improved from baseline to endpoint (all subgroups p<0.01).

Paliperidone palmitate was associated with a clinically meaningful treatment response and well tolerated in non-acute schizophrenia patients previously unsuccessfully treated with conventional depot antipsychotics.