Randomized clinical study of a histamine H3 receptor antagonist for the treatment of adults with attention-deficit hyperactivity disorder.

BACKGROUND: Psychostimulants, including methylphenidate and amphetamine preparations, are commonly prescribed for the treatment of attention-deficit hyperactivity disorder (ADHD) in children and adults. Histamine H3 receptors reside on non-histamine neurons and regulate other neurotransmitters (e.g. acetylcholine, noradrenaline [norepinephrine]) suggesting that H3 antagonists have the potential to improve attention and impulsivity. Research indicates that H3 receptor antagonists due to their novel mechanism of action may have a unique treatment effect offering an important alternative for the treatment of ADHD. Bavisant (JNJ-31001074) is a highly selective, orally active antagonist of the human H3 receptor with a novel mechanism of action, involving wakefulness and cognition, with potential as a treatment for ADHD. OBJECTIVE: The objective of this study was to evaluate the efficacy, safety and tolerability of three dosages of bavisant compared with placebo in adults with ADHD. STUDY DESIGN: This randomized, double-blind, placebo- and active-controlled, parallel-group, multicentre study evaluated three dosages of bavisant (1 mg/day, 3 mg/day or 10 mg/day) and two active controls in adults with ADHD. The study consisted of a screening phase of up to 14 days, a 42-day double-blind treatment phase and a 7-day post-treatment follow-up phase. Efficacy and safety assessments were performed. SETTING: The study was conducted at 37 study centres in the US from April 2009 through January 2010. PARTICIPANTS: Men and women aged 18-55 years with an established diagnosis of ADHD as confirmed by clinician and self-report diagnostic measures were enrolled. INTERVENTION: Participants were randomly assigned equally to one of six treatment groups: placebo, bavisant 1 mg/day, 3 mg/day or 10 mg/day, atomoxetine hydrochloride 80 mg/day or osmotic-release oral system (OROS) methylphenidate hydrochloride 54 mg/day. MAIN OUTCOME MEASURE: The primary efficacy endpoint was the change in the Attention Deficit Hyperactivity Disorder Rating Scale, Version IV (ADHD-RS-IV) total score from baseline (day 1) to the end of the treatment phase (day 42), and included all randomized participants who received one or more doses of study drug and had baseline and one or more post-baseline assessments (intent-to-treat [ITT] population). Safety assessments included treatment-emergent adverse events (TEAEs), laboratory tests and ECG readings. RESULTS: 430 participants were randomized, 424 received one or more doses of study medication and 335 (78%) of those randomized completed the study. Study participants had a mean age of 33.9 years and were predominantly White men. Mean treatment duration ranged from 31.4 to 38.8 days across groups. Mean change from baseline in the total ADHD-RS-IV score at day 42 (primary efficacy endpoint) was -8.8 in the placebo group versus -9.3, -11.2 and -12.2 in the bavisant 1 mg/day, 3 mg/day and 10 mg/day groups, respectively; the change in the 10 mg/day group was not statistically superior to placebo (p=0.161), and hence statistical comparisons of the 1 mg/day and 3 mg/day groups with placebo based on a step-down closed testing procedure were not performed. Mean change from baseline in the total ADHD-RS-IV score at day 42 was superior to placebo in the atomoxetine (-15.3) and OROS methylphenidate (-15.7) groups (p<0.005). Secondary efficacy assessments demonstrated a similar pattern with a non-significant trend towards improvement in the bavisant groups. The two lower dosages showed a good tolerability profile, but the higher dosage of bavisant was less well tolerated, as evidenced by the incidence of total TEAEs (61.8%, 82.4%, 89.0%), and discontinuations due to TEAEs (4.4%, 7.4%, 19.2%) in the bavisant 1 mg/day, 3 mg/day and 10 mg/day groups, respectively, compared with 58.9% and 2.7%, respectively on placebo. In the atomoxetine and OROS methylphenidate groups, the incidence of total TEAEs was 83.8% and 82.4% and discontinuations due to TEAEs was 10.8% and 8.8%, respectively. CONCLUSION: Bavisant, a highly selective, wakefulness-promoting H3 antagonist, did not display significant clinical effectiveness in the treatment of adults with ADHD. CLINICAL TRIAL REGISTRATION NUMBER: NCT00880217.

A randomized trial of paliperidone palmitate and risperidone long-acting injectable in schizophrenia.

Paliperidone palmitate (PP) is a recently (USA) approved injectable new-generation antipsychotic. This 53-wk, Phase-III double-blind study was designed to assess the non-inferiority of PP to risperidone long-acting injectable (RIS-LAI) in schizophrenia treatment. Acutely symptomatic patients (n=749), with a Positive and Negative Syndrome Scale (PANSS) total score between 60 and 120 were randomly allocated to gluteal injections of either (a) PP: 50 mg eq. on days 1 and 8, and flexible dosing [25-100 mg eq. (i.e. 39-156 mg USA dosing)] once-monthly; or (b) RIS-LAI: bi-weekly injections of 25 mg on days 8 and 22, and flexible dosing (25-50 mg) starting from day 36, with allowed oral supplementation. Patients (n=747) were 59% men, 92% white, mean (s.d.) age of 41 (11.95) yr and 45% (n=339) completed the study. Mean (s.d.) change from baseline to endpoint in PANSS total score was: -11.6 (21.22) PP; and -14.4 (19.76) RIS-LAI (per-protocol analysis set, primary measure); least-squares means difference was -2.6 (95% CI -5.84 to 0.61), with a prespecified 5-point non-inferiority margin. PP's suboptimal dosing regimen (<150 mg eq. initial dose) resulted in lower median plasma levels of the active moiety in PP-treated vs. RIS-LAI-treated patients. Insomnia was the most common treatment-emergent adverse event, with a similar incidence in both groups (15%). PP did not demonstrate comparable efficacy to RIS-LAI, which may be attributable to the initiation dosing strategy employed. Tolerability of both treatments was comparable to previous studies, with no new safety signals detected.

Dosing and switching strategies for paliperidone palmitate: based on population pharmacokinetic modelling and clinical trial data.

Paliperidone palmitate is a second-generation, long-acting injectable (LAI) antipsychotic recently approved by the US FDA and European Medicines Agency for use in patients with schizophrenia. This article reviews the recommended dosing regimens for initiation and maintenance treatment with paliperidone palmitate in adult patients with schizophrenia. We also address issues of switching to paliperidone palmitate from other antipsychotics, managing missed doses and dosing in special patient populations. The dosing recommendations that were approved by the FDA and other regulatory agencies around the world are based on the results of population pharmacokinetic (PK) simulations and data from clinical trials that are presented in this review. A one-compartment disposition model with zero/first-order absorption best described the PK of paliperidone palmitate. Population PK models for extended-release paliperidone and long-acting risperidone were also developed and we report the results from these models. The PK profiles for 5000 patients were simulated after paliperidone palmitate injections. The population median and 90% prediction intervals of the simulated plasma concentration versus time profiles after multiple doses are graphically displayed in this review. Based on the data from model-based PK simulations, the approved recommended initiation regimen for paliperidone palmitate is 150 mg equivalent (mg eq.) paliperidone (paliperidone palmitate 234 mg) on day 1 followed by 100 mg eq. paliperidone (paliperidone palmitate 156 mg) on day 8, each administered into the deltoid muscle, using a 1-inch 23-gauge needle in those weighing <90 kg and a 1.5-inch 22-gauge needle in those weighing ≥90 kg. No oral supplementation is required. Monthly maintenance dosing is in the range of 25-150 mg eq. paliperidone (paliperidone palmitate 39-234 mg; recommended dose of 75 mg eq. paliperidone [paliperidone palmitate 117 mg]) injected into the deltoid (needle size is weight adjusted) or gluteal (using a 1.5-inch 22-gauge needle) muscle. The day 8 dose may be administered ±2 days and monthly doses ±7 days, without a clinically significant impact on plasma concentrations. The re-initiation schedule in patients whose last maintenance dose was >6 weeks previously is dependent upon the duration of time since the last paliperidone palmitate injection. In patients with mild renal impairment (creatinine clearance [CL(CR)]: 50-80 mL/min), dosage should be adjusted. No dose adjustment is required in patients with mild or moderate hepatic impairment; no data currently exist regarding severe hepatic impairment. Elderly patients with normal renal function should receive the same dosage as younger adult patients with normal renal function. In the event of an age-related decline in CL(CR), dosage should be adjusted accordingly. Paliperidone palmitate can be initiated the day after discontinuing previous oral antipsychotic treatment. In patients switching from other LAIs (including long-acting risperidone), paliperidone palmitate dosing should be initiated at the time of what would have been the next scheduled injection of the previous LAI, and continued monthly thereafter. In summary, following initiation dosing, paliperidone palmitate is administered on a monthly basis. It is the first of the second-generation antipsychotics to be available and approved with this dosing regimen. Population PK modelling presented in this review has helped provide practical guidance for administering this novel LAI antipsychotic.

A double-blind study of paliperidone palmitate and risperidone long-acting injectable in adults with schizophrenia.

This 13-week double-blind study was designed to assess noninferiority of the recently approved (in the U.S.) injectable atypical antipsychotic paliperidone palmitate (PP) versus risperidone long-acting injectable (RIS-LAI) in adult patients with schizophrenia. Patients (N=1220) were randomized (1:1) to either a) PP: deltoid injections on day 1 (150 mg eq.), day 8 (100 mg eq.), and once-monthly flexible dosing as deltoid or gluteal injections on day 36 (50 mg eq. or 100 mg eq.) and day 64 (50 mg eq. or 100 mg eq. or 150 mg eq.) or b) RIS-LAI: gluteal injections days 8 and 22 (25mg), days 36, 50 (25 or 37.5mg) and days 64, 78 (25, 37.5 or 50mg). RIS-LAI-treated patients received oral supplementation with RIS 1-6 mg/day (days 1 to 28), and PP-treated patients received oral placebo. The safety analysis set (n=1214) included 58% men, 78% white, with mean (SD) baseline PANSS total score: PP, 84.1 (12.09); and RIS-LAI, 83.6 (11.28). Mean (SD) change from baseline to endpoint in PANSS total score decreased similarly in both groups; PP (-18.6 [15.45]) and RIS-LAI (-17.9 [14.24]). PP treatment was noninferior to RIS-LAI (point estimate [95% CI]: 0.4 [-1.62;2.38], per-protocol analysis set [primary analysis]). The tolerability and safety of PP was generally similar to RIS-LAI with no new safety or tolerability findings.

A controlled, evidence-based trial of paliperidone palmitate, a long-acting injectable antipsychotic, in schizophrenia.

Paliperidone palmitate is a long-acting injectable antipsychotic agent. This 13-week, multicenter, randomized (1 : 1 : 1 : 1), double-blind, parallel-group study evaluated the efficacy, safety, and tolerability of fixed 25, 50, and 100 milligram equivalent (mg equiv.) doses of paliperidone palmitate vs placebo administered as gluteal injections on days 1 and 8, then every 4 weeks (days 36 and 64) in 518 adult patients with schizophrenia. The intent-to-treat analysis set (N=514) was 67% men and 67% White, with a mean age of 41 years. All paliperidone palmitate dose groups showed significant improvement vs placebo in the Positive and Negative Syndrome Scale (PANSS) total score (primary efficacy measure; 25 and 50 mg equiv., p=0.02; 100 mg equiv., p<0.001), as well as Clinical Global Impression Severity scores (p< or =0.006) and PANSS negative and positive symptom Marder factor scores (p< or =0.04). The Personal and Social Performance scale showed no significant difference between treatment groups. The overall incidence of treatment-emergent adverse events was similar between groups. Parkinsonism, the most frequently reported extrapyramidal symptom, was reported at similar rates for placebo (5%) and paliperidone palmitate (5-6% across doses). The mean body mass index and mean weight showed relatively small dose-related increases during paliperidone palmitate treatment. Investigator-evaluated injection-site pain, swelling, redness, and induration were similar across treatment groups; scores for patient-evaluated injection-site pain (visual analog scale) were similar across groups and diminished with time. All doses of once-monthly paliperidone palmitate were efficacious and generally tolerated, both locally and systemically. Paliperidone palmitate offers the potential to improve outcomes in adults with symptomatic schizophrenia.

Efficacy and safety of paliperidone palmitate in adult patients with acutely symptomatic schizophrenia: a randomized, double-blind, placebo-controlled, dose-response study.

This 13-week, double-blind study evaluated the efficacy and safety of the atypical antipsychotic paliperidone palmitate (recently approved in the United States) versus placebo administered as monthly gluteal injections (after two initial doses given 1 week apart) in acutely symptomatic patients with schizophrenia. Patients (N=388) were randomly assigned (1 : 1 : 1 : 1) to paliperidone palmitate 50, 100, or 150 mg eq. or placebo. As the 150 mg eq. dose was administered to fewer patients (n=30) than planned, meaningful and definitive conclusions cannot be drawn from the results of this group. The change from baseline in Positive and Negative Syndrome Scale total score at endpoint showed improvement in both paliperidone palmitate 50 and 100 mg eq. groups but was significant only in the 100 mg eq. group (P=0.019). The paliperidone palmitate 50 (P=0.004) and 100 mg eq. (P<0.001) groups showed significant improvement in the Personal and Social Performance score from baseline to endpoint versus placebo. Common adverse events (in >or=2% of patients in any group) more frequent with paliperidone palmitate 50 or 100 mg eq. than placebo (>or=5% difference) were headache, vomiting, extremity pain, and injection site pain. Treatment with paliperidone palmitate (100 mg eq.) was efficacious and all doses tested were tolerable.

Safety and tolerability of oral paliperidone extended-release tablets in elderly patients with schizophrenia: a double-blind, placebo-controlled study with six-month open-label extension.

OBJECTIVE: The objective of this multicenter, international study was to evaluate safety and tolerability of paliperidone extended-release (ER) tablets in elderly (age > or =65 years) patients with schizophrenia. The authors conducted a 6-week, double-blind, randomized, placebo-controlled, optional 24-week open-label extension study. Interventions consisted of flexible, once-daily doses of paliperidone ER (3-12 mg/day; 6-mg starting dose, adjusted in 3-mg dose increments) or placebo (2:1) during double-blind treatment and paliperidone ER only during open-label treatment. Measurements included adverse events, laboratory tests, physical examinations, 12-lead electrocardiograms, movement disorder rating scales, Positive and Negative Syndrome Scale, and Clinical Global Impression scale. The study was not powered to show statistical differences. RESULTS: Patients (N = 114) were predominantly female (73%); mean age was 70 years (double-blind phase). Concomitant disease presence was consistent with that of an older population. During the double-blind phase, discontinuation rates resulting from adverse events were similar between groups (paliperidone ER: 7%, placebo: 8%) as were incidences of treatment-emergent adverse events (paliperidone ER: 67%, placebo: 71%). Serious adverse events occurred in 3% of the paliperidone ER- and 8% of the placebo-treated patients. Elevated prolactin levels occurred in approximately one half of patients. No prolactin- or glucose treatment-related adverse events or noteworthy mean changes in body weight (0 kg [standard deviation: 2.1] and 0 kg [standard deviation: 2.3] for paliperidone ER and placebo, respectively) were observed. Safety and tolerability results in the extension were consistent with the shorter-term results. Efficacy measures did not show consistent statistical improvement between treatment groups. CONCLUSION: Paliperidone ER (3-12 mg/day) treatment over a 30-week period was generally well-tolerated and may improve symptom severity in elderly patients with schizophrenia.

A double-blind, placebo-controlled, randomized study evaluating the effect of paliperidone extended-release tablets on sleep architecture in patients with schizophrenia.

The effects of paliperidone extended-release on sleep architecture in patients with schizophrenia-related insomnia were evaluated in this multicenter, double-blind, randomized, placebo-controlled study. Patients received paliperidone extended-release 9 mg/day or matching placebo during the 14-day double-blind phase. Sleep architecture and sleep continuity were evaluated using polysomnograms. Subjective sleep measures were evaluated daily using the Leeds Sleep Evaluation Questionnaire. Efficacy and safety were also assessed. Thirty-six patients (17 on paliperidone extended-release, 19 on placebo; mean age 32.2 years) completed the study. Paliperidone extended-release treatment vs. placebo resulted in clinically and statistically significant differences in sleep measurements from baseline to endpoint including a reduction in: persistent sleep latency (41 min), sleep onset latency (35 min), number of awakenings after sleep onset (7), time awake in bed (50 min), and stage 1 sleep duration (12 min); prolongation in: total sleep time (53 min), sleep period time (42 min), stage 2 sleep duration (51 min), and rapid eye movement sleep duration (18 min); and an increase in sleep efficiency index (11%). Paliperidone extended-release, compared with placebo, did not exacerbate daytime somnolence and improved symptoms of schizophrenia. Paliperidone extended-release was well tolerated and improved sleep architecture and sleep continuity in patients diagnosed with schizophrenia and concomitant insomnia.

Prevalence and predictors of epoetin hyporesponsiveness in chronic kidney disease patients.

BACKGROUND: The required erythropoiesis-stimulating agent (ESA) dose varies when correcting anaemia in chronic kidney disease (CKD) patients. This analysis was performed to identify the prevalence of and factors associated with ESA hyporesponsiveness. METHODS: This analysis was a post hoc evaluation of epoetin alfa dosage requirements in a subgroup of patients from the Effect of early Correction of Anemia on the Progression of CKD study. The patients in this subgroup were randomly assigned to the high haemoglobin target group (14-15 g/dl for men and 13-14 g/dl for women) and completed a 4-month haemoglobin stabilization phase with complete epoetin dosage data. The relationship of demographics, disease characteristics and laboratory measures with epoetin dosage were evaluated using Pearson's correlation, association measures and analysis of covariance (ANCOVA) models. RESULTS: Of the 93 patients evaluated in this subgroup analysis, 14 (15%) were hyporesponsive to epoetin (maximum dosage >100 IU/kg/week during stabilization). An ANCOVA analysis showed that 52% of the observed variability in epoetin dosage at completion of the stabilization phase could be accounted for by diabetes as the primary cause of kidney disease, angiotensin-converting enzyme (ACE) inhibitor/angiotensin receptor blocker (ARB) use, proteinuria, transferrin saturation, age, pre-treatment haemoglobin, geographical region, serum iron and body mass index (BMI). Unidentified patient characteristics accounted for an additional 16% of the dosage variance. CONCLUSIONS: Older age, higher BMI, anaemia, ACE inhibitor/ARB use and diabetes as the primary cause of kidney disease are associated with increased epoetin requirements when normalizing haemoglobin in anaemic CKD patients.

Effect of early correction of anemia on the progression of CKD.

BACKGROUND: This study is designed to assess the effect of early and complete correction of anemia by using recombinant human erythropoietin (epoetin) alfa on the progression of chronic kidney disease (CKD). METHODS: Patients were randomly assigned to achieve high (13 to 15 g/dL [130 to 150 g/L]) or low (11 to 12 g/dL [110 to 120 g/L]) hemoglobin-level targets during 4 months of stabilization, followed by 36 months of maintenance. Glomerular filtration rate (GFR) decrease was measured by using iohexol clearance. Quality of life, nutrition, and safety also were monitored. RESULTS: Because of labeling changes for subcutaneous administration of epoetin alfa (Eprex; Johnson and Johnson, Schaffhausen, Switzerland), the study was terminated prematurely. There were 195 patients enrolled in each group; 108 high-hemoglobin and 133 low-hemoglobin patients entered the maintenance phase. Mean maintenance duration was 7.4 months for the high-hemoglobin group and 8.3 months for the low-hemoglobin group. GFR decrease was numerically, but not statistically significantly, lower with the high-hemoglobin group (0.058 versus 0.081 mL/min/1.73 m2/mo [< 0.01 mL/s/1.73 m2/mo]). Physical quality-of-life measures showed trends (Role-Physical, P = 0.055; Physical Function, P = 0.083) or statistically significant improvement (Vitality, P = 0.042) with high hemoglobin levels at the end of the stabilization phase. Adverse events were similar between groups. Cardiovascular adverse events occurred in 25% of the high-hemoglobin and 18% of the low-hemoglobin patients (P = 0.137). Neither epoetin dosage nor hemoglobin level was associated with cardiovascular adverse events or death. CONCLUSION: These data suggest that normalization of hemoglobin levels in patients with CKD is safe. Longer duration studies are needed to clarify efficacy benefits with high hemoglobin levels.