Efficacy and safety of once-monthly injection of paliperidone palmitate in hospitalized Asian patients with acute exacerbated schizophrenia: an open-label, prospective, noncomparative study

INTRODUCTION: This single-group, open-label, prospective, noncomparative, multicenter, Phase IV study explored the efficacy and tolerability of paliperidone palmitate (PP) in hospitalized patients with acute exacerbation of schizophrenia.

METHODS: Asian patients of either sex, between 18 and 65 years of age, diagnosed with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) with acute exacerbations within the previous 4 weeks, were enrolled. Intramuscular PP was initiated at doses of 150 milligram equivalent (mg eq) (day 1) and 100 mg eq (day 8), followed by a monthly maintenance dose between 75 mg eq and 150 mg eq (days 36 and 64). Primary efficacy endpoint was the change from baseline in the Positive and Negative Syndrome Scale (PANSS) total score (last-observation-carried-forward) at week 13.

RESULTS: Of the 212 enrolled patients, 152 (71.7%) completed the 13-week treatment; withdrawal of consent (24 [11.3%] patients) was the most common reason for study discontinuation. Mean (standard deviation) PANSS total score from baseline (90.0 [17.41]) improved significantly at day 4 (-6.1 [9.27]; 95% confidence interval: -7.38, -4.85; P<0.001) and week 13 endpoint (-23.9 [23.24]; 95% confidence interval: -27.10, -20.78; P<0.001). Similarly, the secondary endpoints (Clinical Global Impression-Severity, Physical and Social Performance, each PANSS subscale, and Marder factor scores) improved significantly from baseline to week 13 endpoint (P<0.001 for all). At week 13, 112/210 (53.3%) patients had a 40% improvement in the PANSS total score (responder rate), and 133/212 (62.7%) patients were ready for hospital discharge. Overall, 139 (65.6%) patients experienced at least one treatment-emergent adverse event (TEAE). Most common (>5%) TEAEs were hyperprolactinemia, constipation, nasopharyngitis, insomnia, increased weight, and tremor. Worsening of schizophrenia (3.3%) and sinus bradycardia (2.0%) were serious TEAEs; no deaths were reported.

CONCLUSION: PP was generally tolerable and efficacious in a hospital setting for the treatment of acute exacerbated schizophrenia with significant improvements in psychotic symptoms, social functioning, and severity of illness.