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Anticuerpos Monoclonales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Estados Unidos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/diagnóstico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Farmacovigilancia , Sistemas de Registro de Reacción Adversa a Medicamentos , United States Food and Drug AdministrationRESUMEN
BACKGROUND: Use of antipsychotics to treat behavioural symptoms of dementia has been associated with increased risks of mortality and stroke. Little is known about individual patient characteristics that might be associated with bad or good outcomes. AIMS: We examined the risperidone clinical trial data to look for individual patient characteristics associated with these adverse outcomes. METHOD: Data from all double-blind randomised controlled trials of risperidone in dementia patients (risperidone n = 1009, placebo n = 712) were included. Associations between characteristics and outcome were analysed based on crude incidences and exposure-adjusted incidence rates, and by time-to-event analyses using Cox proportional hazards regression. Interactions between treatment (risperidone or placebo) and characteristic were analysed with a Cox proportional hazards regression model with main effects for treatment and characteristic in addition to the interaction term. RESULTS: Baseline complications of depression (treatment by risk factor interaction on cerebrovascular adverse event (CVAE) hazard ratio (HR): P = 0.025) and delusions (P = 0.043) were associated with a lower relative risk of CVAE in risperidone-treated patients (HR = 1.47 and 0.54, respectively) compared to not having the complication (HR = 5.88 and 4.16). For mortality, the only significant baseline predictor in patients treated with risperidone was depression, which was associated with a lower relative risk (P<0.001). The relative risk of mortality was increased in risperidone patients treated with anti-inflammatory medications (P = 0.021). CONCLUSIONS: Only anti-inflammatory medications increased mortality risk with risperidone. The reduced risks of CVAE in patients with comorbid depression and delusions, and of mortality with depression, may have clinical implications when weighing the benefits and risks of treatment with risperidone in patients with dementia.
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Antipsicóticos/efectos adversos , Trastornos Cerebrovasculares/inducido químicamente , Trastornos Cerebrovasculares/mortalidad , Demencia/tratamiento farmacológico , Risperidona/efectos adversos , HumanosRESUMEN
BACKGROUND: Paliperidone palmitate has been associated with serum prolactin elevations in some patients. However, few individuals with elevated prolactin levels (hyperprolactinemia) have symptomatic potentially prolactin-related adverse events (PPR-AEs). OBJECTIVE: To quantify rates of hyperprolactinemia in subjects treated with the newly marketed paliperidone palmitate long-acting injection (PP-LAI) in randomized clinical trials, summarize rates of PPR-AEs in those trials by sex and dose, and determine how many PPR-AEs required treatment. METHODS: Numbers and rates of investigator-reported hyperprolactinemia and PPR-AEs were obtained from the sponsor's clinical trial database and have been included in regulatory filings. Results were tabulated for males, females, and overall, and by dose administered, using descriptive statistics. Those requiring treatment were described as well. RESULTS: There were 3173 subjects (61.4% males) exposed to PP-LAI in 10 clinical trials; 2831 (89.2%) patients had recorded prolactin levels, including 1759 males (90.3% of exposed males) and 1072 females (87.5% of exposed females). Overall, at any time, prolactin levels were elevated for 38.8% of the subjects (39.5% for males and 37.7% for females; p = 0.354 between sexes). However, there was no significant correlation between monthly dose and proportion of subjects with elevated prolactin levels (p = 0.109). There were 115 PPR-AEs in 107 patients (3.4%); 51 (44.3% of PPR-AEs) cases represented asymptomatic hyperprolactinemia. The remaining 64 symptomatic PPR-AEs affected 2.0% of the total number of subjects. Fifteen events in 13 participants (0.41% of patients or 4.7 events/1000 patients) required treatment. CONCLUSIONS: Clinicians should periodically assess patients on paliperidone palmitate for any PPR-AEs and carefully assess the benefits and risks when managing these effects.
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Antipsicóticos/efectos adversos , Hiperprolactinemia/inducido químicamente , Isoxazoles/efectos adversos , Palmitatos/efectos adversos , Adulto , Femenino , Humanos , Hiperprolactinemia/sangre , Masculino , Persona de Mediana Edad , Palmitato de Paliperidona , Prolactina/sangre , Adulto JovenRESUMEN
BACKGROUND: There are no previous reports of paliperidone palmitate's (PP) long term tolerability or pharmacokinetics of the highest dose in patients with schizophrenia. This study evaluates safety and tolerability, as well as pharmacokinetics, of the highest marketed dose of PP (150 mg eq. [234 mg]) in stable patients with schizophrenia over a 1-year period. METHODS: In this 1-year prospective study, eligible patients (aged 18-65 years; Positive and Negative Syndrome Scale's total score ≤ 70) received an initial deltoid injection of PP 150 mg eq. The second injection one week later and subsequent once-monthly injections were deltoid or gluteal. All injections were to be PP 150 mg eq. Patients willing to participate in intensive pharmacokinetic sampling were classified as Treatment A. Patients unwilling to undergo intensive pharmacokinetic sampling or unable to tolerate the 150 mg eq. dose (consequently receiving flexible doses of 50, 100 or 150 mg eq.) were classified as Treatment B. RESULTS: Of the 212 patients (safety analysis set), 73% were men; 45% white; 20% black; 34% Asians; mean (SD) age 41 (10.2) years, and mean (SD) baseline Positive and Negative Syndrome Scale total score 54.9 (9.03). A total of 53% (n = 113) patients completed the study and 104 received PP 150 mg eq. throughout. Mean (SD) mode dose of PP was 144.8 (19.58) mg eq. The dosing initiation regimen resulted in rapidly achieved and maintained therapeutic paliperidone levels over the study (average concentrations during the dosing interval were 34.7, 40.0, and 47.8 ng/mL after the 2nd, 8th, and 14th injection respectively). Most frequent (≥ 10%) treatment-emergent adverse events were nasopharyngitis (n = 37), insomnia (n = 32), injection-site pain (n = 32), headache (n = 28), and tachycardia (n = 27). Akathisia (n = 19) and tremor (n = 11) were the most common extrapyramidal adverse events. 33 patients had an SAE and 27 discontinued due to treatment-emergent adverse events. No deaths were reported. Mean (SD) weight change from baseline was 2.5 (5.41) kg at endpoint. Patients' psychoses remained stable. CONCLUSIONS: Safety results after one-year therapy with the highest available dose of once-monthly paliperidone palmitate were consistent with results from previous studies, with no new concerns noted. Plasma concentrations were within the expected range. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01150448.
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Antipsicóticos/uso terapéutico , Isoxazoles/uso terapéutico , Palmitatos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Psicología del Esquizofrénico , Adolescente , Adulto , Anciano , Antipsicóticos/administración & dosificación , Antipsicóticos/efectos adversos , Antipsicóticos/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Inyecciones Intramusculares/efectos adversos , Inyecciones Intramusculares/estadística & datos numéricos , Isoxazoles/administración & dosificación , Isoxazoles/efectos adversos , Isoxazoles/farmacocinética , Masculino , Persona de Mediana Edad , Palmitato de Paliperidona , Palmitatos/administración & dosificación , Palmitatos/efectos adversos , Palmitatos/farmacocinética , Estudios Prospectivos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Esquizofrenia/sangre , Insuficiencia del TratamientoRESUMEN
BACKGROUND: Women of childbearing potential are often treated with monoclonal antibodies to control chronic and debilitating inflammatory diseases. Remicade® (innovator infliximab [IFX]) may cross the placenta after the first trimester of pregnancy. Hence, evidence is needed to optimize treatment while carefully weighing benefits and risks to the mother and child. Here, we report on birth and infant outcomes (up to 2 years) following gestational exposure to IFX based on a summary of cumulative pregnancy reports in women exposed to IFX during pregnancy from the Janssen global safety database. METHODS: Prospective and medically confirmed safety data on IFX-exposed pregnancies from Janssen's global safety surveillance database since authorization in 1998 are summarized. Descriptive statistics were used to summarize pregnancy and infant outcomes overall, by disease and timing of exposure. RESULTS: As of 23 August 2018, 1850 maternally IFX-exposed pregnancies with known outcomes were identified from the safety database. Of the 1850 pregnancies (mean age 29.7 years), 1526 (82.5%) resulted in live births. When reported, most women had Crohn's disease (67.7%) or ulcerative colitis (18.4%), and 82.8% of live births were exposed to IFX in the first trimester. Spontaneous abortion/intrauterine death/ectopic pregnancy/molar pregnancy (12.1%), preterm births (9.2%), low birth weight infants (3.6%), congenital anomalies (2.0%), and infant infections (1.2%) were documented. The type of congenital anomalies and frequency of serious infant infections observed were consistent with the general population. Frequencies of congenital anomalies and other adverse outcomes were similar in women exposed to IFX in the first trimester and those exposed in the third trimester. More preterm births (13-18.8%) and infant complications (8.7-12.5%) were reported with concomitant immunosuppressant use. CONCLUSIONS: The observed prevalence of adverse pregnancy and infant outcomes including congenital anomalies following exposure to IFX did not exceed estimates reported for the general population and no unexpected patterns were observed.
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Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/administración & dosificación , Infliximab/efectos adversos , Complicaciones del Embarazo/tratamiento farmacológico , Resultado del Embarazo , Anomalías Inducidas por Medicamentos , Aborto Espontáneo/inducido químicamente , Adulto , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Femenino , Humanos , Embarazo , Nacimiento Prematuro/inducido químicamente , Prevalencia , Vigilancia de Productos Comercializados , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
INTRODUCTION: Janssen received reports of needle detachments for Risperdal® CONSTA® and, in response, redesigned the kit. OBJECTIVE: The study objective was to estimate the rate of Risperdal® CONSTA® needle detachments prior to and after the introduction of a redesigned kit. METHODS: This retrospective study used record abstraction in the US Department of Veterans Affairs (VA). The 3 phases included: (1) a pilot study for methods evaluation in a sample of 6 hospitals with previously reported detachments; (2) a baseline study to ascertain the baseline detachment rate; and (3) a follow-up study to ascertain the rate for the redesigned kit. Administrative codes and natural language processing with clinical review were used to identify detachments. RESULTS: Pilot: we identified a subset of spontaneously reported detachments and several previously unreported events. In the baseline study (original device), from January through December 2013, 22 needle detachments were identified among 47,934 administrations of the drug in a census of administrations in the VA; an incidence of 0.0459%. In the follow-up study (redesigned device), from December 2015 through December 2016, there were 14 reported detachments in 41,819 injections, 0.0335%. This represents a reduction of 27% from the baseline. CONCLUSION: This approach enabled us to identify needle detachments we would not have otherwise found ("solicited"). However, it likely resulted in incomplete outcome ascertainment. While this may have resulted in lower overall rates, it did not bias the comparison of the baseline and follow-up studies. The results showed that the redesigned Risperdal® CONSTA® kit reduced the incidence of needle detachment events in the VA. FUNDING: Janssen Pharmaceuticals, Inc.
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BACKGROUND: A significant number of women of childbearing age have schizophrenia or other psychoses. This means that there is a considerable risk of in utero exposure to risperidone due to maternal use. OBJECTIVE: To determine whether in utero exposure to the atypical antipsychotic risperidone is associated with poor pregnancy and fetal/neonatal outcomes. METHODS: A search of the Benefit Risk Management Worldwide Safety database, using a selection of preferred terms from the Medical Dictionary of Regulatory Activities, was performed to identify all cases of pregnancy or fetal/neonatal outcomes reported in association with risperidone treatment from its first market launch (international birth date, 1 June 1993) to 31 December 2004. The main measures were the patterns and reporting rates of pregnancy (stillbirth and spontaneous and induced abortion) and fetal/neonatal outcomes (congenital abnormalities, perinatal syndromes and withdrawal symptoms) for women administered risperidone during pregnancy. RESULTS: Overall, 713 pregnancies were identified in women who were receiving risperidone. Data were considered prospective in 516 of these, and retrospective in the remaining 197 cases. The majority of the known adverse pregnancy and fetal/neonatal outcomes were retrospectively reported. Of the 68 prospectively reported pregnancies with a known outcome, organ malformations and spontaneous abortions occurred 3.8% and 16.9% (when the 15 induced abortions were excluded from the denominator, as they were predominantly undertaken for nonmedical reasons), respectively, a finding consistent with background rates of the general population. There were 12 retrospectively reported pregnancies involving major organ malformations, the most frequently reported of which affected the heart, brain, lip and/or palate. There were 37 retrospectively reported pregnancies involving perinatal syndromes, of which 21 cases involved behavioural or motor disorders. In particular, there was a cluster of cases reporting tremor, jitteriness, irritability, feeding problems and somnolence, which may represent a withdrawal-emergent syndrome. CONCLUSION: This comprehensive review of the Benefit Risk Management Worldwide Safety database for case reports of risperidone exposure during pregnancy represents the largest ever published dataset documenting pregnancy outcomes for women taking the atypical antipsychotic risperidone. It indicates that in utero exposure to risperidone does not appear to increase the risk of spontaneous abortions, structural malformations and fetal teratogenic risk above that of the general population. Self-limited extrapyramidal effects in neonates were observed after maternal exposure to risperidone during the third trimester of pregnancy. Risperidone should only be used during pregnancy if the benefits outweigh the potential risks.
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Aborto Espontáneo/inducido químicamente , Antipsicóticos/efectos adversos , Trastornos Mentales/tratamiento farmacológico , Resultado del Embarazo/epidemiología , Risperidona/efectos adversos , Anomalías Inducidas por Medicamentos/epidemiología , Aborto Inducido , Adulto , Bases de Datos Factuales , Femenino , Humanos , Recién Nacido , Exposición Materna/efectos adversos , Persona de Mediana Edad , Embarazo , Trimestres del Embarazo/efectos de los fármacos , Estudios Retrospectivos , Medición de Riesgo , Gestión de Riesgos , Síndrome de Abstinencia a SustanciasAsunto(s)
Antipsicóticos/efectos adversos , Isoxazoles/efectos adversos , Síndrome de QT Prolongado/inducido químicamente , Pirimidinas/efectos adversos , Animales , Antipsicóticos/administración & dosificación , Ensayos Clínicos como Asunto/métodos , Evaluación Preclínica de Medicamentos/métodos , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Humanos , Isoxazoles/administración & dosificación , Palmitato de Paliperidona , Pirimidinas/administración & dosificación , Factores de RiesgoRESUMEN
The objective of these 2 phase 1, open-label, 2-treatment, single-sequence studies was to evaluate the effect of repeated oral doses of divalproex sodium extended-release (ER) on the pharmacokinetics (PK) of a single dose of paliperidone ER in healthy participants (study 1), and the effect of multiple doses of paliperidone ER on the steady-state PK of valproic acid (VPA) in patients with psychiatric disorders (study 2), respectively. In study 1 healthy participants received, in a fixed sequential order, treatment A, paliperidone ER 12 mg (day 1); treatment B, VPA 1000 mg (2 × 500 mg divalproex sodium ER) once daily (days 5 to 18) and paliperidone ER 12 mg (day 15). In study 2 patients received treatment A, VPA (days 1-7); treatment B, VPA + paliperidone ER 12 mg (days 8-12). Divalproex sodium ER doses (study 2) were individualized such that systemic therapeutic VPA exposure from prior treatment was maintained on entry into the study. PK assessments were performed at prespecified time points (paliperidone days 1 and 15 [study 1]; VPA days 7 and 12 [study 2]). The oral bioavailability of paliperidone was increased by an estimated 51% (Cmax ) and 51%-52% (AUCs) when coadministered with divalproex sodium ER. No effect on the steady-state plasma concentration of VPA was observed following repeated coadministration with paliperidone ER: the 90%CI around the VPA exposure ratios for the 2 treatments was within the 80%-125% bioequivalence criteria for Cmax,ss and AUCτ . Both VPA and paliperidone ER were well tolerated, and no new safety concerns were identified.
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Antimaníacos/sangre , Antipsicóticos/sangre , Trastornos Mentales/sangre , Trastornos Mentales/tratamiento farmacológico , Palmitato de Paliperidona/sangre , Ácido Valproico/sangre , Adulto , Antimaníacos/administración & dosificación , Antipsicóticos/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/metabolismo , Interacciones Farmacológicas/fisiología , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Palmitato de Paliperidona/administración & dosificación , Comprimidos , Ácido Valproico/administración & dosificaciónRESUMEN
IMPORTANCE: Treatment nonadherence and relapse are common problems in patients with schizophrenia. The long-acting 3-month formulation of paliperidone palmitate, owing to its extended elimination half-life, may offer a valuable therapeutic option for these patients. OBJECTIVE: To evaluate the efficacy and safety of the 3-month formulation of paliperidone palmitate vs placebo in delaying time to relapse of schizophrenia symptoms. DESIGN, SETTING, AND PARTICIPANTS: This randomized, multicenter trial conducted from April 26, 2012, through April 9, 2014, in 8 countries consisted of 4 phases: 3-week screening phase, flexible-dose 17-week open-label transition phase, 12-week open-label maintenance phase, and open-ended double-blind (DB) phase. Of the 506 patients enrolled (aged 18-70 years; DSM-IV-TR diagnosis of schizophrenia), 305 were randomized to 3-month paliperidone palmitate (n = 160) or placebo (n = 145) in the DB phase. INTERVENTIONS: Patients received once-monthly doses of the 1-month formulation of paliperidone palmitate (50, 75, 100, or 150 mg eq) during the transition phase, followed by a single dose of the 3-month formulation (3.5 times the stabilized dose of once-monthly paliperidone palmitate) during the maintenance phase. Stabilized patients were randomized to receive either a fixed dose of 3-month paliperidone palmitate (175, 263, 350, or 525 mg eq) or placebo once every 3 months during the DB phase. MAIN OUTCOMES AND MEASURES: Time from randomization to the first relapse event (time to relapse) in the DB phase. RESULTS: In the interim analysis, time to first relapse was significantly different in favor of the paliperidone palmitate group vs the placebo group (hazard ratio = 3.45; 95% CI, 1.73-6.88; P < .001); median time to relapse was 274 days for placebo but not estimable for 3-month paliperidone palmitate. An independent data monitoring committee recommended early study termination due to efficacy. In the DB phase, 183 of 305 patients (62% with 3-month paliperidone palmitate; 58% with placebo) had at least 1 treatment-emergent adverse event; those noted more frequently in the group receiving paliperidone palmitate than in the placebo group were headache (9% vs 4%), weight increased (9% vs 3%), nasopharyngitis (6% vs 1%), and akathisia (4% vs 1%). CONCLUSIONS AND RELEVANCE: Compared with placebo, the 3-month formulation of paliperidone palmitate administered 4 times yearly significantly delayed time to relapse in patients with schizophrenia. The 3-month formulation was generally tolerable and has a safety profile consistent with other marketed paliperidone formulations. TRIAL REGISTRATION: clinicaltrials.gov Identifier:NCT01529515.
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Isoxazoles/uso terapéutico , Palmitatos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Prevención Secundaria/métodos , Adolescente , Adulto , Anciano , Antipsicóticos/administración & dosificación , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Preparaciones de Acción Retardada/efectos adversos , Preparaciones de Acción Retardada/uso terapéutico , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Isoxazoles/administración & dosificación , Isoxazoles/efectos adversos , Masculino , Persona de Mediana Edad , Palmitato de Paliperidona , Palmitatos/administración & dosificación , Palmitatos/efectos adversos , Esquizofrenia/prevención & control , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: We analyzed data retrieved through a PubMed search of randomized, placebo-controlled trials of first-generation antipsychotic long-acting injectables (haloperidol decanoate, bromperidol decanoate, and fluphenazine decanoate), and a company database of paliperidone palmitate, to compare the benefit-risk ratio in patients with schizophrenia. METHODS: From the eight studies that met our selection criteria, two efficacy and six safety parameters were selected for calculation of number needed to treat (NNT), number needed to harm (NNH), and the likelihood of being helped or harmed (LHH) using comparisons of active drug relative to placebo. NNTs for prevention of relapse ranged from 2 to 5 for paliperidone palmitate, haloperidol decanoate, and fluphenazine decanoate, indicating a moderate to large effect size. RESULTS: Among the selected maintenance studies, NNH varied considerably, but indicated a lower likelihood of encountering extrapyramidal side effects, such as akathisia, tremor, and tardive dyskinesia, with paliperidone palmitate versus placebo than with first-generation antipsychotic depot agents versus placebo. This was further supported by an overall higher NNH for paliperidone palmitate versus placebo with respect to anticholinergic use and Abnormal Involuntary Movement Scale positive score. LHH for preventing relapse versus use of anticholinergics was 15 for paliperidone palmitate and 3 for fluphenazine decanoate, favoring paliperidone palmitate. CONCLUSION: Overall, paliperidone palmitate had a similar NNT and a more favorable NNH compared with the first-generation long-acting injectables assessed.
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OBJECTIVE: First-month data of a 13-week acute schizophrenia study were used to compare paliperidone palmitate to oral risperidone during initiation of long-acting injectable risperidone. DESIGN: Double-blind, randomized study. SETTING: Outpatient or inpatient. PARTICIPANTS: Adults with established (≥1 year) schizophrenia. Those assigned to risperidone long-acting injectable (n=460) received 25mg on Days 8 and 22 with oral risperidone (l-6mg) supplementation for the first 28 days. The paliperidone palmitate group (n=453) received 150mg eq. on Day 1, l00mg eq. on Day 8, and oral placebo supplementation for the first 28 days. MEASUREMENTS: Positive and Negative Syndrome Scale, Personal and Social Performance Scale, Clinical Global Impression-Severity score, and responder rate (percentage of patients with ≥30% reduction in PANSS total score). An analysis of covariance model estimated least-square mean differences between treatment groups. A post-hoc analysis of efficacy data for the period of interest, i.e., at the time points before and after the first 28 days, was conducted. RESULTS: Positive and Negative Syndrome Scale, Personal and Social Performance Scale, Clinical global Impression-Severity scores showed similar efficacy between the treatment groups during the first weeks of treatment, corresponding to the risperidone long-acting injection initiation period. Mean Positive and Negative Syndrome Scale total score at baseline was 84.7 for paliperidone palmitate and 84.4 for oral risperidone, on Day 22 was 73.6 and 74.1, respectively, and on Day 36 was 71.8 and 72.8, respectively. Overall incidence of adverse events in the first 28 days was generally similar (45% for paliperidone palmitate vs. 35% for oral risperidone), except for injection site pain (4.6% vs. 0.7%). Similar active moiety plasma concentrations were obtained during this period. CONCLUSION: During the first month, paliperidone palmitate without oral supplementation has similar efficacy and safety to oral risperidone (during initiation of risperidone long-acting injectable) in acutely exacerbated schizophrenia.
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BACKGROUND: Paliperidone extended-release (paliperidone ER) is an approved oral antipsychotic medication (dosing range 3-12 mg/day) for treatment of schizophrenia and schizoaffective disorder in adults. METHODS: In this 3-arm, double-blind, placebo- and active-controlled, parallel-group study, paliperidone ER 1.5 mg was assessed to determine the lowest efficacious dose in patients (N = 201) with acute schizophrenia. Paliperidone ER 6 mg was included for assay sensitivity. RESULTS: Patients (intent-to-treat analysis set) had a mean age of 39.4 years; 74% were men, 43% Asian, and 40% black. The baseline mean (SD) Positive and Negative Syndrome Scale (PANSS) total score was 92.6 (13.02) and the mean (SD) change from baseline to endpoint was: placebo group, -11.4 (20.81); paliperidone ER 1.5 mg group, -8.9 (23.31); and paliperidone ER 6 mg group, -15.7 (26.25). Differences between paliperidone groups versus placebo were not significant (paliperidone ER 1.5 mg [p = 0.582], paliperidone ER 6 mg, [p = 0.308]). Safety results of paliperidone ER 1.5 mg and placebo were comparable. The most frequently reported treatment emergent adverse events (≥10%) were: placebo group-headache (15.6%) and psychotic disorder (14.1%); paliperidone ER 1.5 mg group-insomnia (13.6%); and paliperidone ER 6 mg group-headache (11.4%), insomnia (10%), and tremor (10%). CONCLUSIONS: In this study, paliperidone ER 1.5 mg did not demonstrate efficacy in patients with acute schizophrenia. A markedly high placebo response was noted. Assay sensitivity with the 6 mg dose was not established. Paliperidone ER 1.5 mg was generally tolerable with a safety profile comparable to placebo.