Quantitative projection of human brain penetration of the H3 antagonist PF-03654746 by integrating rat-derived brain partitioning and PET receptor occupancy.

1. Unbound brain drug concentration (Cb,u), a valid surrogate of interstitial fluid drug concentration (CISF), cannot be directly determined in humans, which limits accurately defining the human Cb,u:Cp,u of investigational molecules. 2. For the H3R antagonist (1R,3R)-N-ethyl-3-fluoro-3-[3-fluoro-4-(pyrrolidin-1-lmethyl)phenyl]cyclobutane-1-carboxamide (PF-03654746), we interrogated Cb,u:Cp,u in humans and nonhuman primate (NHP). 3. In rat, PF-03654746 achieved net blood-brain barrier (BBB) equilibrium (Cb,u:Cp,u of 2.11). 4. In NHP and humans, the PET receptor occupancy-based Cp,u IC50 of PF-03654746 was 0.99 nM and 0.31 nM, respectively, which were 2.1- and 7.4-fold lower than its in vitro human H3 Ki (2.3 nM). 5. In an attempt to understand this higher-than-expected potency in humans and NHP, rat-derived Cb,u:Cp,u of PF-03654746 was integrated with Cp,u IC50 to identify unbound (neuro) potency of PF-03654746, nIC50. 6. The nIC50 of PF-03654746 was 2.1 nM in NHP and 0.66 nM in human which better correlated (1.1- and 3.49-fold lower) with in vitro human H3 Ki (2.3 nM). 7. This correlation of the nIC50 and in vitro hH3 Ki suggested the translation of net BBB equilibrium of PF-03654746 from rat to NHP and humans, and confirmed the use of Cp,u as a reliable surrogate of Cb,u. 8. Thus, nIC50 quantitatively informed the human Cb,u:Cp,u of PF-03654746.

Large-scale deep learning analysis to identify adult patients at risk for combined and common variable immunodeficiencies.

BACKGROUND: Primary immunodeficiency (PI) is a group of heterogeneous disorders resulting from immune system defects. Over 70% of PI is undiagnosed, leading to increased mortality, co-morbidity and healthcare costs. Among PI disorders, combined immunodeficiencies (CID) are characterized by complex immune defects. Common variable immunodeficiency (CVID) is among the most common types of PI. In light of available treatments, it is critical to identify adult patients at risk for CID and CVID, before the development of serious morbidity and mortality. METHODS: We developed a deep learning-based method (named "TabMLPNet") to analyze clinical history from nationally representative medical claims from electronic health records (Optum® data, covering all US), evaluated in the setting of identifying CID/CVID in adults. Further, we revealed the most important CID/CVID-associated antecedent phenotype combinations. Four large cohorts were generated: a total of 47,660 PI cases and (1:1 matched) controls. RESULTS: The sensitivity/specificity of TabMLPNet modeling ranges from 0.82-0.88/0.82-0.85 across cohorts. Distinctive combinations of antecedent phenotypes associated with CID/CVID are identified, consisting of respiratory infections/conditions, genetic anomalies, cardiac defects, autoimmune diseases, blood disorders and malignancies, which can possibly be useful to systematize the identification of CID and CVID. CONCLUSIONS: We demonstrated an accurate method in terms of CID and CVID detection evaluated on large-scale medical claims data. Our predictive scheme can potentially lead to the development of new clinical insights and expanded guidelines for identification of adult patients at risk for CID and CVID as well as be used to improve patient outcomes on population level.

Primary immunodeficiencies (PI) are disorders that weaken the immune system, increasing the incident of life-threatening infections, organ damage and the development of cancer and autoimmune diseases. Although PI is estimated to affect 1-2% of the global population, 70-90% of these patients remain undiagnosed. Many patients are diagnosed during adulthood, after other serious diseases have already developed. We developed a computational method to analyze the clinical history from a large group of people with and without PI. We focused on combined (CID) and common variable immunodeficiency (CVID), which are among the least studied and most common PI subtypes, respectively. We could identify people with CID or CVID and combinations of diseases and symptoms which could make it easier to identify CID or CVID. Our method could be used to more readily identify adults at risk of CID or CVID, enabling treatment to start earlier and their long-term health to be improved.

Parental assessment of executive function and internalizing and externalizing behavior in primary hypertension after anti-hypertensive therapy.

OBJECTIVE: To determine the change in parental ratings of executive function and behavior in children with primary hypertension after anti-hypertensive therapy. STUDY DESIGN: Parents of subjects with untreated hypertension and control subjects completed the Behavior Rating Inventory of Executive Function (BRIEF) to assess behavioral correlates of executive function and the Child Behavior Checklist (CBCL) to assess internalizing and externalizing behaviors. Subjects with hypertension subsequently received anti-hypertensive therapy to achieve casual blood pressure (BP)<95th percentile. After 12 months, all parents again completed the BRIEF and CBCL. RESULTS: Twenty-two subjects with hypertension and 25 normotensive control subjects underwent both baseline and 12-month assessments. The BP of subjects with hypertension improved (24-hour systolic BP [SBP] load: mean baseline versus 12-months, 60% versus 25%, P<.001). Parent ratings of executive function improved from baseline to 12 months in the subjects with hypertension (BRIEF Global Executive Composite T-score, Delta=-5.9, P=0.001), but not in the normotensive control subjects (Delta=-0.36, P=.83). In contrast, T-scores on the CBCL Internalizing and Externalizing summary scales did not change significantly from baseline to 12 months in either subjects with hypertension or control subjects. CONCLUSIONS: Children with hypertension demonstrated improvement in parental ratings of executive function after 12 months of anti-hypertensive therapy.

Diagnosis and Treatment Options for Preschoolers with Attention-Deficit/Hyperactivity Disorder.

Objective: The Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), classifies attention-deficit/hyperactivity disorder (ADHD) as a neurodevelopmental disorder, with symptoms becoming apparent as early as the preschool years. Early recognition can lead to interventions such as parent/teacher-administered behavior therapy, the recommended first-line treatment for preschool patients. There are few data, however, to inform the use of second-line, pharmacotherapy options in this population. In this review, we identified recent literature on the diagnosis and treatment of ADHD in preschool children. Methods: A PubMed and clinicaltrials.gov search was conducted for trials assessing efficacy or safety of ADHD medications in children aged <6 years. Diagnostic methods and criteria focusing on recognition of ADHD in preschool children were also surveyed. Results: The DSM-5 describes different manifestations of ADHD in preschool versus school-aged children, but does not list separate criteria by age group. Importantly, behaviors indicative of ADHD in older children may be developmentally appropriate in preschool children. Several behavioral rating scales have been validated in children younger than 6 years of age for assessing ADHD. The Preschool ADHD Treatment Study (PATS) has provided the most extensive efficacy and safety data on methylphenidate (MPH) for ADHD in preschoolers to date, with significant improvement in ADHD symptoms observed with MPH compared with placebo, although adverse event-related discontinuation was higher in PATS compared with studies of MPH for ADHD in school-aged children. Since PATS was conducted, few studies designed to assess ADHD medication effectiveness in preschool children have been published. One article reported significant improvement in ADHD symptoms with MPH (immediate release) versus placebo, two studies showed no difference between MPH and risperidone or MPH plus risperidone in relief of ADHD symptoms, and one study demonstrated the efficacy of atomoxetine versus placebo for ADHD symptoms in preschoolers. Conclusions: Further research is needed on pharmacotherapy for preschool children with ADHD.

Parental assessments of internalizing and externalizing behavior and executive function in children with primary hypertension.

OBJECTIVE: To determine the relations between hypertension and parental ratings of behavior and executive functions in children with primary hypertension and to examine the potential moderating influence of obesity. STUDY DESIGN: Hypertensive and normotensive control groups were matched for age, sex, race, intelligence quotient, maternal education, household income, and obesity. Parents completed the Child Behavior Checklist to assess Internalizing and Externalizing problems and the Behavior Rating Inventory of Executive Function to assess behavioral correlates of executive function. RESULTS: Thirty-two hypertensive subjects and 32 normotensive control subjects (aged 10 to 18 years) were enrolled. On the Child Behavior Checklist, hypertensives had higher Internalizing T-scores (53 vs 44.5, P = .02) with 37% falling within the clinically significant range vs 6% of control subjects (P = .005). Internalizing score increased with increasing body mass index percentile in hypertensive but not normotensive subjects. Hypertensives had worse Behavior Rating Inventory of Executive Function Global Executive Composite T-scores compared with control subjects (50 vs 43, P = .009). CONCLUSIONS: Children with both hypertension and obesity demonstrate higher rates of clinically significant internalizing problems, and hypertensives (irrespective of obesity) demonstrate lower parental ratings of executive function compared with normotensive control subjects.

Clonidine for attention-deficit/hyperactivity disorder: I. Efficacy and tolerability outcomes.

OBJECTIVE: To determine the efficacy and safety of clonidine, used alone or in combination with methylphenidate, in treating attention-deficit/hyperactivity disorder (ADHD). METHOD: A 16-week, randomized, double-blind, placebo-controlled clinical trial was conducted in 122 children, ages 7 to 12, with any subtype of ADHD, randomly assigned to clonidine, methylphenidate, clonidine in combination with methylphenidate, or placebo according to a 2 x 2 factorial design. In two successive 4-week titration periods, clonidine (or matching placebo) and added methylphenidate (or matching placebo) were adjusted to optimal doses and then continued for 8 weeks. The primary efficacy outcome was changed from baseline to week 16 on the Conners Teachers Abbreviated Symptom Questionnaire. Secondary outcomes included the Conners Abbreviated Symptom Questionnaire for Parents and the Children's Global Assessment Scale. RESULTS: On the Conners Teachers Abbreviated Symptom Questionnaire, clonidine was not found to improve ADHD symptoms, whereas subjects treated with methylphenidate showed significant improvement compared to those not treated with methylphenidate. Subjects treated with clonidine had greater improvements on the Conners Abbreviated Symptom Questionnaire for Parents and Children's Global Assessment Scale, but also a higher rate of sedation compared with subjects not treated with clonidine. CONCLUSIONS: Based on the Conners Teachers Abbreviated Symptom Questionnaire, methylphenidate offers the best combination of efficacy and tolerability for ADHD. Clonidine was well tolerated despite the frequency of sedation and did offer some benefit.

Clonidine for attention-deficit/hyperactivity disorder: II. ECG changes and adverse events analysis.

OBJECTIVE: To examine the safety and tolerability of clonidine used alone or with methylphenidate in children with attention-deficit/hyperactivity disorder (ADHD). METHOD: In a 16-week multicenter, double-blind trial, 122 children with ADHD were randomly assigned to clonidine (n = 31), methylphenidate (n = 29), clonidine and methylphenidate (n = 32), or placebo (n = 30). Doses were flexibly titrated up to 0.6 mg/day for clonidine and 60 mg/day for methylphenidate (both with divided dosing). Groups were compared regarding adverse events and changes from baseline to week 16 in electrocardiograms and vital signs. RESULTS: There were more incidents of bradycardia in subjects treated with clonidine compared with those not treated with clonidine (17.5% versus 3.4%; p =.02), but no other significant group differences regarding electrocardiogram and other cardiovascular outcomes. There were no suggestions of interactions between clonidine and methylphenidate regarding cardiovascular outcomes. Moderate or severe adverse events were more common in subjects on clonidine (79.4% versus 49.2%; p =.0006) but not associated with higher rates of early study withdrawal. Drowsiness was common on clonidine, but generally resolved by 6 to 8 weeks. CONCLUSIONS: Clonidine, used alone or with methylphenidate, appears safe and well tolerated in childhood ADHD. Physicians prescribing clonidine should monitor for bradycardia and advise patients about the high likelihood of initial drowsiness.

Relative Bioavailability of Methylphenidate Extended-release Chewable Tablets Chewed Versus Swallowed Whole.

PURPOSE: Methylphenidate hydrochloride extended-release chewable tablet (MPH ERCT) is approved for treatment of attention deficit hyperactivity disorder in patients aged 6 years and older. This article evaluates the pharmacokinetic parameters and relative bioavailability of MPH ERCT when chewed versus swallowed whole. METHODS: In this open-label, single-dose, 3-period, 3-treatment crossover study, 12 healthy adult volunteers were randomly assigned to treatment sequence. In each period, subjects received a single 40-mg dose of the assigned treatment (MPH ERCT chewed, MPH ERCT swallowed whole, or methylphenidate extended-release oral suspension [MEROS]). Blood samples for pharmacokinetic analysis were collected for 24 hours postdose. Key pharmacokinetic parameters included Cmax, AUC0-t, and AUC0-∞. FINDINGS: The geometric mean values for AUC0-t, AUC0-∞, and Cmax were similar for MPH ERCT chewed, MPH ERCT swallowed whole, and MEROS. In all pairwise between-treatment comparisons, the 90% CIs of the geometric mean ratios for AUC0-t, AUC0-∞, and Cmax were fully contained within the bioequivalence range of 80% to 125%. Early exposure over the first 4 hours after dosing (AUC0-4) was similar for MPH ERCT chewed versus swallowed whole; AUC0-4 was approximately 15% lower for MPH ERCT, either chewed or swallowed, compared with MEROS. Each treatment was generally well tolerated. IMPLICATIONS: There was no difference in overall rate or extent of exposure of methylphenidate when MPH ERCT was chewed versus swallowed whole by healthy volunteers.

Optimization of Methylphenidate Extended-Release Chewable Tablet Dose in Children with ADHD: Open-Label Dose Optimization in a Laboratory Classroom Study.

OBJECTIVE: To examine methylphenidate extended-release chewable tablets (MPH ERCT) dose patterns, attention-deficit/hyperactivity disorder (ADHD) symptom scores, and safety during the 6-week, open-label (OL) dose-optimization period of a phase 3, laboratory classroom study. METHODS: Boys and girls (6-12 years) diagnosed with ADHD were enrolled. MPH ERCT was initiated at 20 mg/day; participants were titrated in 10-20 mg/day increments weekly based on efficacy and tolerability (maximum dose, 60 mg/day). Dose-optimization period efficacy assessments included the ADHD Rating Scale (ADHD-RS-IV), analyzed by week in a post hoc analysis using a mixed-effects model for repeated measures with final optimized dose (20, 30/40, or 50/60 mg), visit, final optimized dose and visit interaction, and baseline score as terms. Adverse events (AEs) and concomitant medications were collected throughout the study. RESULTS: Mean MPH ERCT daily dose increased weekly from 29.4 mg/day after the first dose adjustment at week 1 (n = 90) to 42.8 mg/day after the final adjustment at week 5 (n = 86). Final optimized MPH ERCT dose ranged from 20 to 60 mg/day. Mean final optimized MPH ERCT dose ranged from 40.0 mg/day in 6-8 year-old participants to 44.8 mg/day for 11-12 year-old participants. There was a progressive decrease in mean (standard deviation) ADHD-RS-IV total score from 40.1 (8.72) at baseline to 12.4 (7.88) at OL week 5, with similar improvement patterns for hyperactivity/impulsivity and inattentiveness subscale scores. Participants optimized to MPH ERCT 50/60 mg/day had a significantly higher mean (standard error) ADHD-RS-IV score at baseline compared with participants optimized to MPH ERCT 20 mg/day (42.4 [1.34] vs. 35.1 [2.55]; p = 0.013). Treatment-emergent AEs were reported by 65/90 (72.2%) participants in the dose-optimization period. CONCLUSIONS: Dose-optimization period results describing relationships between change in ADHD symptom scores and final optimized MPH ERCT dose will be valuable for clinicians optimizing MPH ERCT dose.

An evaluation of neurocognitive status and markers of immune activation as predictors of time to death in advanced HIV infection.

BACKGROUND: Several markers of immune activation have been identified as potential prognostic markers for human immunodeficiency virus (HIV)-associated morbidity and mortality, but the results from studies are conflicting. OBJECTIVE: To evaluate whether neurocognitive status and baseline levels of plasma and cerebrospinal fluid tumor necrosis factor alpha (TNF-alpha), macrophage chemoattractant protein 1 (MCP-1), matrix metalloproteinase 2 (MMP-2), or macrophage colony-stimulating factor (M-CSF) are associated with time to death in a cohort with advanced HIV infection. DESIGN: Cohort study. SETTING: Enrollees in the Northeast AIDS Dementia Study. PARTICIPANTS: Three hundred twenty-nine subjects who were positive for HIV-1 and had a CD4 cell count of less than 200/microL (or <300/microL but with cognitive impairment at baseline) were assessed for CD4 cell count, neurocognitive status, pertinent demographic and clinical variables, and plasma and cerebrospinal fluid HIV RNA, TNF-alpha, MCP-1, MMP-2, and M-CSF levels. MAIN OUTCOME MEASURES: Cox proportional hazards regression models were used to examine the associations between the variables of interest (using time-dependent covariates, where applicable) and time to death, adjusting for possible confounders. RESULTS: There were 50 deaths in the cohort after a median of 25.2 months of follow-up. The cumulative incidences of death were 7% at 1 year and 16% at 2 years. In Cox proportional hazards regression analyses adjusting for demographic, clinical, and immunological variables, HIV-associated dementia (hazard rate, 6.10; P = .001) was significantly associated with time to death; (log) plasma MCP-1 level (hazard rate, 3.38; P = .08) trended toward significance. CONCLUSION: In patients with advanced HIV infection, HIV-associated dementia is an independent predictor of time to death.

Diagnosis and treatment of attention deficit hyperactivity disorder.

Attention-deficit hyperactivity disorder (ADHD) is a neurobehavioral disorder characterized by signs and symptoms of inattention, hyperactivity, and impulsivity that typically begin in childhood. ADHD can persist into adulthood, causing impairments in occupational performance and peer and family relationships. This article reviews the epidemiology, diagnosis, and treatment of ADHD.

Effect of Food Intake on the Pharmacokinetics of a Novel Methylphenidate Extended-Release Oral Suspension for Attention Deficit Hyperactivity Disorder.

We conducted an open-label, single-dose, randomized, crossover study in healthy adults to assess the impact of food on the bioavailability of 60 mg methylphenidate extended-release oral suspension (MEROS; Quillivant XR™)-a long-acting stimulant for the treatment of attention deficit hyperactivity disorder-by comparing the pharmacokinetic parameters under fed and fasting conditions. When MEROS 60 mg was administered under fed conditions compared with fasting conditions, the exposure of methylphenidate (d enantiomer) was higher, with a mean area under the plasma concentration-vs-time curve (AUC)0-t of 160.2 ng·h/mL vs 140.4 ng·h/mL, and a mean AUC0-inf of 163.2 ng·h/mL vs 143.7 ng·h/mL, respectively. The ratios of the ln-transformed geometric means for methylphenidate for AUC0-t and AUC0-inf were 119.5% (90%CI, 115.7% to 123.5%) and 119.0% (90%CI, 115.2% to 122.8%), respectively, within the standard 80% to 125% bioequivalence acceptance range indicating no food effect on the overall exposure (rate and extent). There was a small increase in the peak plasma concentration (127.6% [90%CI, 119.9% to 135.8%]). However, this effect was small and not likely to be clinically significant. Overall, MEROS 60 mg was safe in both the fed and fasting condition when administered to healthy volunteers in this study.

Efficacy and Safety of a Chewable Methylphenidate Extended-Release Tablet in Children with Attention-Deficit/Hyperactivity Disorder.

OBJECTIVE: This phase 3, laboratory classroom study assessed the efficacy and safety of methylphenidate hydrochloride extended-release chewable tablets (MPH ERCT) compared with placebo in children with attention-deficit/hyperactivity disorder (ADHD). METHODS: Following a 6-week, open-label, dose-optimization period, children 6-12 years of age (n = 90) with ADHD were randomly assigned to double-blind MPH ERCT at the final optimized dose (20-60 mg/day) or placebo. After 1 week of double-blind treatment, efficacy was assessed predose and 0.75, 2, 4, 8, 10, 12, and 13 hours postdose in a laboratory classroom setting. The primary efficacy measure was the average of postdose Swanson, Kotkin, Agler, M-Flynn, and Pelham (SKAMP) Rating Scale-Combined scores, analyzed using a mixed-model, repeated-measures analysis. Secondary efficacy measures included Permanent Product Measure of Performance (PERMP) total number of problems attempted and total number of problems correct. Safety assessments included adverse event (AE) monitoring and the Columbia-Suicide Severity Rating Scale (C-SSRS). RESULTS: MPH ERCT treatment statistically significantly reduced the average of all postdose SKAMP-Combined scores versus placebo (least-squares mean difference [95% confidence interval], -7.0 [-10.9, -3.1]; p < 0.001). Statistically significant treatment differences in SKAMP-Combined scores were observed at 2 hours postdose through 8 hours postdose (p-values <0.001). Statistically significant differences between MPH ERCT and placebo in PERMP total number of problems attempted and total number of problems correct were observed at 0.75 hours postdose through 8 hours postdose (p-values ≤0.049). Common AEs in the open-label period (≥5%) were decreased appetite, upper abdominal pain, mood swings, irritability, insomnia, upper respiratory tract infection (URTI), dysgeusia, and headache; URTI was the only AE reported by >1 subject receiving MPH ERCT in the double-blind period (placebo: URTI, contusion, wound, and initial insomnia). No suicidal ideation or behavior was reported on the C-SSRS at baseline or at any postbaseline assessment. CONCLUSIONS: MPH ERCT 20-60 mg significantly improved ADHD symptoms compared with placebo at 2 hours postdose through at least 8 hours postdose. MPH ERCT was generally safe and well tolerated, with a safety profile consistent with other MPH ER formulations. ClinicalTrials.gov Identifier: NCT01654250. www.clinicaltrials.gov/ct2/show/NCT01654250 .

Determination of receptor occupancy in the presence of mass dose: [11C]GSK189254 PET imaging of histamine H3 receptor occupancy by PF-03654746.

Measurements of drug occupancies using positron emission tomography (PET) can be biased if the radioligand concentration exceeds "tracer" levels. Negative bias would also arise in successive PET scans if clearance of the radioligand is slow, resulting in a carryover effect. We developed a method to (1) estimate the in vivo dissociation constant Kd of a radioligand from PET studies displaying a non-tracer carryover (NTCO) effect and (2) correct the NTCO bias in occupancy studies taking into account the plasma concentration of the radioligand and its in vivo Kd. This method was applied in a study of healthy human subjects with the histamine H3 receptor radioligand [11C]GSK189254 to measure the PK-occupancy relationship of the H3 antagonist PF-03654746. From three test/retest studies, [11C]GSK189254 Kd was estimated to be 9.5 ± 5.9 pM. Oral administration of 0.1 to 4 mg of PF-03654746 resulted in occupancy estimates of 71%-97% and 30%-93% at 3 and 24 h post-drug, respectively. NTCO correction adjusted the occupancy estimates by 0%-15%. Analysis of the relationship between corrected occupancies and PF-03654746 plasma levels indicated that PF-03654746 can fully occupy H3 binding sites ( ROmax = 100%), and its IC50 was estimated to be 0.144 ± 0.010 ng/mL. The uncorrected IC50 was 26% higher.

Methylmercury and neurodevelopment: longitudinal analysis of the Seychelles child development cohort.

BACKGROUND: The Seychelles Child Development Study (SCDS) has been longitudinally following a cohort of over 700 children enrolled in 1989. Their mothers consumed a diet high in fish during pregnancy. Repeated examination of the SCDS cohort at six different ages through age 11 years has shown no pattern of adverse effects. Some early appearing beneficial associations between both prenatal and postnatal hair MeHg and several child development endpoints were noted. We hypothesized these might be related to micronutrients in the fish, but they were not found when the children reached middle school age. These findings suggest that the associations observed between MeHg and developmental outcomes may vary with developmental stage. METHOD: We examined the main cohort of the SCDS to determine if this might be true using a longitudinal multiple regression analysis design that focused on those endpoints that were repeatedly measured at different ages. The primary endpoint analyzed was global cognition, involving a measure of developmental quotient or IQ. Secondary analyses included other domains such as Reading and Mathematics scholastic achievement, social behavior, and memory. Analyses involved two different approaches, one including incorporation of a passage of time variable, the other including a difference of scores across time points. RESULTS: No significant associations were found between prenatal MeHg exposure and any of the repeatedly measured endpoints. CONCLUSIONS: These results suggest that even when individual subject variance is controlled there was no consistent pattern of associations between child development outcomes and prenatal exposures to MeHg from maternal consumption of a diet high in fish. The Seychellois diet contains about 10 times more ocean fish than is typically consumed by US citizens. Our primary focus on IQ should further inform growing scientific interest in the analysis of the risks and benefits of fish consumption on overall cognitive ability.

Psychological testing in adolescent medicine.

Psychological and neuropsychological assessment remains an important aspect of clinical evaluation in adolescents with psychiatric and neurologic disorders. The primary care practitioner can refer for psychological and neuropsychological assessment when cognitive, behavioral, or psychiatric problems appear to be affecting the adolescent's learning, psychosocial development, or overall functioning. The most appropriate assessment depends upon the diagnostic issue at hand. Most referrals will include IQ and achievement testing to assess for learning disabilities; behavioral and personality assessment to aid in psychiatric diagnosis and treatment planning; and neuropsychological testing for more complex issues, such as the impact of neurological disorders and injuries on cognition and behavior. The patient can be referred to the school psychologist for IQ and achievement testing that complements any additional testing that may be required to help determine the best intervention. Psychological assessment can be invaluable in the early identification and intervention of learning, behavioral, and psychiatric difficulties in adolescents.

Single-dose Pharmacokinetic Properties and Relative Bioavailability of a Novel Methylphenidate Extended-release Chewable Tablet Compared With Immediate-release Methylphenidate Chewable Tablet.

PURPOSE: A novel methylphenidate hydrochloride extended-release chewable tablet (MPH ERCT) was developed to potentially address an unmet need for patients with attention-deficit/hyperactivity disorder, especially children, who cannot or will not swallow tablets or would prefer the convenience of a chewable tablet. This randomized, open-label, crossover trial compared the pharmacokinetic properties and relative bioavailability of MPH ERCT with an MPH chewable immediate-release tablet (IR MPH) formulation in healthy adults. METHODS: Healthy men and women 18 to 55 years of age were randomly assigned to MPH ERCT 40 mg or 40 mg IR MPH administered in 2 equal doses of 20 mg 6 hours apart with a 7-day washout period. Plasma concentrations of MPH at selected time points up to 24 hours were measured, and pharmacokinetic parameters were determined using a noncompartmental approach in the SAS (Version 9.2) PROC general linear model procedure. FINDINGS: A total of 33 participants were enrolled in the study; 31 participants were included in the pharmacokinetic analysis. The exposure ratios for MPH ERCT and IR MPH (MPH ERCT/IR MPH) for area under the analyte concentration versus time curves (AUC) from time zero to the last measurable analyte concentration (AUC0-last) (87.64%; 95% CI, 84.96-90.41) and AUC0-∞ (89.11%; 95% CI, 86.57-91.73) were within the standard 80% to 125% bioequivalence acceptance criteria. Mean Cmax for MPH ERCT and IR MPH was 12.51 ng/mL and 15.57 ng/mL, respectively; mean time to Cmax was 4.16 hours and 6.43 hours, respectively. The mean Cmax of MPH ERCT was 80% of the Cmax of IR MPH due to a higher peak concentration that occurs after the second dose of IR MPH. All adverse events were mild in severity. IMPLICATIONS: The relative bioavailability of MPH ERCT 40 mg, based on the exposure (AUC), was comparable to that of IR MPH 40 mg administered in 2 equal doses of 20 mg 6 hours apart. Both formulations were generally well tolerated.

Efficacy and tolerability of low-dose donepezil in schizophrenia.

There have been many advancements in the pharmacologic treatment of schizophrenia; however, negative symptoms and cognitive impairment remain an intractable part of this illness. Donepezil is an anticholinesterase inhibitor with cognitive enhancing effects approved for the treatment of Alzheimer disease that has shown some benefit in the treatment of schizophrenia. In this study, 15 inpatients at a state hospital with a history of schizophrenia were administered donepezil in a randomized, double-blind, crossover design. Neurocognitive testing and psychiatric ratings were completed at baseline and at regular intervals for 18 weeks. Results indicated that donepezil treatment was associated with modest improvements in psychiatric symptoms and improved verbal learning. These results suggest that donepezil may be helpful as adjunctive therapy for the treatment of psychiatric symptoms and cognitive impairment in a subgroup of schizophrenic patients.

ADHD treatment with once-daily OROS methylphenidate: interim 12-month results from a long-term open-label study.

OBJECTIVE: Few treatment studies of attention-deficit/hyperactivity disorder (ADHD) extend beyond a few months. This article reports an interim analysis of a 24-month study evaluating the 12-month tolerability and effectiveness of a once-daily OROS formulation of methylphenidate (OROS MPH) in children with ADHD. METHOD: Children, aged 6-13 years, with ADHD who participated in previous controlled studies and were MPH responders, received once-daily OROS MPH in this multicenter, open-label, nonrandomized study. Effectiveness was evaluated monthly by parents/caregivers and schoolteachers using validated rating scales (e.g., IOWA Conners). Safety and adverse events assessments involved objective (e.g., vital signs, growth) and subjective (sleep quality, tics) reporting. RESULTS: Seventy-one percent of subjects (289/407) completed 12 months' treatment. Effectiveness was maintained throughout 12 months as demonstrated by stable IOWA Conners ratings and sustained improvements in peer interaction and Global Assessment Scale scores. OROS MPH was well tolerated, with adverse events similar to those expected with short-acting stimulant medication. OROS MPH had minimal impact on sleep quality and tics. There were no clinically meaningful changes in blood pressure, pulse, or height. The apparent absence of meaningful changes is tempered by the fact that children were MPH responders and were medicated at baseline, most for extended periods prior to enrollment. CONCLUSION: In this open-label study, once-daily OROS MPH treatment appears to be well tolerated and effectiveness was maintained for up to 12 months in these children with ADHD.

Emergence of tics in children with ADHD: impact of once-daily OROS methylphenidate therapy.

OBJECTIVES: While stimulants are the recognized first-line choice of pharmacotherapy for ADHD, reports that they may induce or exacerbate tics have tended to limit their use in ADHD children who have a history of tics or a family history of Tourette's syndrome. This study analyzes the incidence of tics reported across five studies of children with ADHD who received methylphenidate (MPH)-based therapy as part of the clinical development program for once-daily OROS MPH (CONCERTA McNeil Consumer & Specialty Pharmaceuticals, Fort Washington, PA). METHODS: Data were analyzed from three placebo-controlled, active-controlled studies (studies 1-3) lasting 1-4 weeks, and two open-label studies lasting 2 years (study 4) and 9 months (study 5), respectively. During the course of the studies, parents were asked at the end of each week of treatment (studies 1 and 2), biweekly (study 3), or monthly (for the first year of study 4, then at 3-month intervals thereafter) whether their child had experienced tics. Tics could also be reported as adverse events in the two open-label studies. RESULTS: Pooled data from the three placebo-controlled studies showed that the incidence of tics was not significantly different across all three treatment groups (OROS MPH, 4.0%; MPH tid, 2.3%; placebo, 3.7%, p = 0.5249). During the first year of the 2-year open-label study, the monthly incidence of tics remained constant, at approximately 5%. Analysis of tic episodes per patient in this study found no correlation between an OROS MPH dose and the frequency of tic episodes. The risk of tic episodes was higher in patients with a history of tics than in those with no history of tics (33% versus 7%, p < 0.0001). However, only 2 children with a history of tics (4%) withdrew from therapy because of their tics. CONCLUSIONS: These data suggest that MPH-based therapy does not significantly induce or exacerbate tics in children with ADHD.