Executive functioning profiles from the BRIEF across pediatric medical disorders: Age and diagnosis factors.

OBJECTIVE: To compare Executive Functioning (EF) profiles across several pediatric medical conditions and explored the influence of age of diagnosis and evaluation. METHODS: This was a retrospective, cross sectional study of 734 children ages 5-18 across five medical groups [brain tumor, leukemia (ALL), epilepsy (EPI), Neurofibromatosis Type 1 (NF1), and Ornithine Transcarbamylase Deficiency (OTC-D)], ADHD controls, and matched healthy controls. We compared groups across the subscales of a parent completed Behavior Rating Inventory of Executive Functioning (BRIEF) using MANOVA. Separate MANOVAs were conducted to look at age factors. RESULTS: The ADHD group differed from all other groups and had the highest level of reported EF problems. The NF1 and OTC-D groups differed significantly from the healthy comparison group for overall EF problems, while the EPI and cancer groups did not. Working Memory was the most elevated subscale across medical groups, followed by Plan/Organize. Children with medical disorders were two to four times as likely as healthy controls to have clinically significant problems in several EF domains. There was a main effect for age at diagnosis and age at evaluation.. CONCLUSIONS: A subset of children with medical disorders were found to have parent reported EF difficulties, with particular vulnerability noted in working memory and organizational/planning skills. This has relevance for the development of interventions that may be helpful across disorders. Children with particular diagnoses and earlier age of diagnosis and evaluation had greater reported EF problems

Establishing a consortium for the study of rare diseases: The Urea Cycle Disorders Consortium

The Urea Cycle Disorders Consortium (UCDC) was created as part of a larger network established by the National Institutes of Health to study rare diseases. This paper reviews the UCDC's accomplishments over the first 6years, including how the Consortium was developed and organized, clinical research studies initiated, and the importance of creating partnerships with patient advocacy groups, philanthropic foundations and biotech and pharmaceutical companies

Ammonia control and neurocognitive outcome among urea cycle disorder patients treated with glycerol phenylbutyrate

UnlabelledGlycerol phenylbutyrate is under development for treatment of urea cycle disorders (UCDs), rare inherited metabolic disorders manifested by hyperammonemia and neurological impairment. We report the results of a pivotal Phase 3, randomized, double-blind, crossover trial comparing ammonia control, assessed as 24-hour area under the curve (NH3 -AUC0-24hr ), and pharmacokinetics during treatment with glycerol phenylbutyrate versus sodium phenylbutyrate (NaPBA) in adult UCD patients and the combined results of four studies involving short- and long-term glycerol phenylbutyrate treatment of UCD patients ages 6 and above. Glycerol phenylbutyrate was noninferior to NaPBA with respect to ammonia control in the pivotal study, with mean (standard deviation, SD) NH3 -AUC0-24hr of 866 (661) versus 977 (865) μmol·h/L for glycerol phenylbutyrate and NaPBA, respectively. Among 65 adult and pediatric patients completing three similarly designed short-term comparisons of glycerol phenylbutyrate versus NaPBA, NH3 -AUC0-24hr was directionally lower on glycerol phenylbutyrate in each study, similar among all subgroups, and significantly lower (P < 0.05) in the pooled analysis, as was plasma glutamine. The 24-hour ammonia profiles were consistent with the slow-release behavior of glycerol phenylbutyrate and better overnight ammonia control. During 12 months of open-label glycerol phenylbutyrate treatment, average ammonia was normal in adult and pediatric patients and executive function among pediatric patients, including behavioral regulation, goal setting, planning, and self-monitoring, was significantly improved.ConclusionGlycerol phenylbutyrate exhibits favorable pharmacokinetics and ammonia control relative to NaPBA in UCD patients, and long-term glycerol phenylbutyrate treatment in pediatric UCD patients was associated with improved executive function (ClinicalTrials.gov NCT00551200, NCT00947544, NCT00992459, NCT00947297). (HEPATOLOGY 2012)

Ammonia control and neurocognitive outcome among urea cycle disorder patients treated with glycerol phenylbutyrate

BACKGROUND: Glycerol phenylbutyrate is under development for treatment of urea cycle disorders (UCDs), rare inherited metabolic disorders manifested by hyperammonemia and neurological impairment. METHODS: We report the results of a pivotal phase 3, randomized, double-blind, crossover trial comparing ammonia control, assessed as 24-hour area under the curve (NH(3)-AUC(0-24hr)), and pharmacokinetics during treatment with glycerol phenylbutyrate versus sodium phenylbutyrate (NaPBA) in adult UCD patients and the combined results of 4 studies involving short- and long-term glycerol phenylbutyrate treatment of UCD patients ages 6 and above. RESULTS: Glycerol phenylbutyrate was non-inferior to NaPBA with respect to ammonia control in the pivotal study, with mean (SD) NH(3)-AUC(0-24hr) of 866 (661) versus 977 (865) μmol·h/L for glycerol phenylbutyrate and NaPBA, respectively. Among 65 adult and pediatric patients completing 3 similarly designed short term comparisons of glycerol phenylbutyrate versus NaPBA, NH(3)-AUC(0-24hr) was directionally lower on glycerol phenylbutyrate in each study, similar among all subgroups, and significantly lower (p<0.05) in the pooled analysis, as was plasma glutamine. The 24-hour ammonia profiles were consistent with slow release behavior of glycerol phenylbutyrate and better overnight ammonia control. During 12 months of open label glycerol phenylbutyrate treatment, average ammonia was normal in adult and pediatric patients and executive function among pediatric patients, including behavioral regulation, goal setting, planning and self-monitoring, was significantly improved. CONCLUSIONS: Glycerol phenylbutyrate exhibits favorable pharmacokinetics and ammonia control relative to NaPBA in UCD patients, and long-term glycerol phenylbutyrate treatment in pediatric patients was associated with improved executive function (ClinicalTrials.gov NCT00551200, NCT00947544, NCT00992459, NCT00947297)