Informed consent and assent guide for paediatric clinical trials in Europe.

OBJECTIVE: Clinical trial sponsors spend considerable resources preparing informed consent (IC) and assent documentation for multinational paediatric clinical trial applications in Europe due to the limited and dispersed patient populations, the variation of national legal and ethical requirements, and the lack of detailed guidance. The aim of this study was to design new easy-to-use guide publicly available on European Medicines Agency's, Enpr-EMA website for all stakeholders. METHODS: Current EU legal, ethical and regulatory guidance for paediatric clinical trials were collated, analysed and divided into 30 subject elements in two tables. The European Network of Young Person's Advisory Group reviewed the data and provided specific comments. A three-level recommendation using 'traffic light' symbols was designed for four age groups of children, according to relevance and the requirements. RESULTS: A single guide document includes two tables: (1) general information and (2) trial-specific information. In the age group of 6-9 years old, 92% of the trial-specific subject elements can be or should be included in the IC discussion. Even in the youngest possible age group (2-5 years old children), the number of elements considered was, on average, 52%. CONCLUSION: The EU Clinical Trial Regulation (2014) does not contain specific requirements exclusively for paediatric clinical trials. This work is the first to extensively collate all the current legal, regulatory and ethical documentation on the IC process, together with input from adolescents. This guide may increase the ethical standards in paediatric clinical trials.

Safety and efficacy of delayed release rabeprazole in 1- to 11-month-old infants with symptomatic GERD.

AIM: : The efficacy and safety of rabeprazole, a proton pump inhibitor, were studied in infants with gastroesophageal reflux disease (GERD). METHODS: Infants ages 1 to 11 months, with symptomatic GERD resistant to conservative therapy and/or previous exposure to acid-suppressive medications, were screened. After scoring >16 on a GERD symptom score (Infant Gastroesophageal Reflux Questionnaire-Revised [I-GERQ]), 344 infants were enrolled in a 1- to 3-week open-label (OL) phase and received rabeprazole 10 mg/day. Following caregiver-rated clinical improvement during the OL phase, patients were randomized to placebo, rabeprazole 5 mg, or rabeprazole 10 mg in the ensuing 5-week double-blind (DB) withdrawal phase. Primary endpoints evaluated from DB baseline to the end of the DB withdrawal phase included frequency of regurgitation, weight-for-age z score, and daily and weekly GERD symptom scores. RESULTS: Overall, 231 (86%) of the 268 randomized infants (placebo: 90; rabeprazole 5 mg: 90; rabeprazole 10 mg: 88) completed the study. Efficacy endpoints were similarly improved during the OL phase in all of the groups, and continued improving during the DB withdrawal phase with no difference between the placebo and combined rabeprazole groups. Mean decrease in frequency of regurgitation (-0.79 vs -1.20 times per day; P = 0.168), in I-GERQ-Revised scores (-3.6 [-25%] vs -3.9 points [-27%]; P = 0.960), in I-GERQ-Daily Diary scores (-1.87 [-19%] vs -1.85 [-19%]; P = 0.968), and increase in weight-for-age z scores (mean [standard deviation]: 0.11 [0.329] vs 0.14 [0.295]; P = 0.440) indicated equal improvement. Equal percentages (47%) reported adverse events in placebo and combined rabeprazole groups, with no new safety signals emerging. CONCLUSIONS: In those infants with GERD who improved with rabeprazole during the OL phase, improvements in symptoms and weight were similar in those who continued rabeprazole and those withdrawn to placebo during a 5-week DB phase.

The newly developed CRF1-receptor antagonists, NGD 98-2 and NGD 9002, suppress acute stress-induced stimulation of colonic motor function and visceral hypersensitivity in rats.

Corticotropin releasing factor receptor 1 (CRF1) is the key receptor that mediates stress-related body responses. However to date there are no CRF1 antagonists that have shown clinical efficacy in stress-related diseases. We investigated the inhibitory effects of a new generation, topology 2 selective CRF1 antagonists, NGD 98-2 and NGD 9002 on exogenous and endogenous CRF-induced stimulation of colonic function and visceral hypersensitivity to colorectal distension (CRD) in conscious rats. CRF1 antagonists or vehicle were administered orogastrically (og) or subcutaneously (sc) before either intracerebroventricular (icv) or intraperitoneal (ip) injection of CRF (10 µg/kg), exposure to water avoidance stress (WAS, 60 min) or repeated CRD (60 mmHg twice, 10 min on/off at a 30 min interval). Fecal pellet output (FPO), diarrhea and visceromotor responses were monitored. In vehicle (og)-pretreated rats, icv CRF stimulated FPO and induced diarrhea in >50% of rats. NGD 98-2 or NGD 9002 (3, 10 and 30 mg/kg, og) reduced the CRF-induced FPO response with an inhibitory IC50 of 15.7 and 4.3 mg/kg respectively. At the highest dose, og NGD 98-2 or NGD 9002 blocked icv CRF-induced FPO by 67-87% and decreased WAS-induced-FPO by 23-53%. When administered sc, NGD 98-2 or NGD 9002 (30 mg/kg) inhibited icv and ip CRF-induced-FPO. The antagonists also prevented the development of nociceptive hyper-responsivity to repeated CRD. These data demonstrate that topology 2 CRF1 antagonists, NGD 98-2 and NGD 9002, administered orally, prevented icv CRF-induced colonic secretomotor stimulation, reduced acute WAS-induced defecation and blocked the induction of visceral sensitization to repeated CRD.

Pregabalin is a potent and selective ligand for α(2)δ-1 and α(2)δ-2 calcium channel subunits.

Pregabalin, a synthetic branched chain γ-amino acid with anticonvulsant, anxiolytic, and analgesic activities, has been shown to bind with high affinity to the voltage-gated calcium channel α(2)δ subunit. Given the broad therapeutic utility of pregabalin, a series of experiments was undertaken to determine the potency, selectivity, and specificity of pregabalin's receptor-binding profile at α(2)δ-1 and α(2)δ-2 subunits of voltage-gated calcium channels along with 38 widely studied receptors and channels. Receptor autoradiography was used to assess regional-binding density of pregabalin throughout the rat spinal cord and brain. In addition, a series of studies using in vivo electrophysiological recordings of γ-aminobutyric acid (GABA)(A)- and GABA(B)-evoked currents was undertaken to determine the interaction of pregabalin with GABAergic receptor subtypes. Together, the results of these studies demonstrate potent and selective binding of pregabalin to α(2)δ-1 and α(2)δ-2 subunits in native and recombinant human and porcine systems. Pregabalin did not interact with any of the 38 receptors and ion channels evaluated, and a variety of central nervous system (CNS)-targeted therapeutic drugs did not show activity at the α(2)δ subunits of voltage-gated calcium channels. Receptor autoradiography demonstrated extensive [(3)H]-pregabalin binding throughout the CNS, with high-level binding in the cortex, hippocampus, cerebellum, dorsal horn of the spinal cord, and amygdala. Finally, receptor-binding and electrophysiological techniques failed to show evidence of an interaction between pregabalin and GABA(A) or GABA(B) receptors. These studies suggest that the clinical effects of pregabalin are likely due to direct and selective interactions with α(2)δ-1 and α(2)δ-2 subunits of voltage-gated calcium channels.

Discovery of N-(1-ethylpropyl)-[3-methoxy-5-(2-methoxy-4-trifluoromethoxyphenyl)-6-methyl-pyrazin-2-yl]amine 59 (NGD 98-2): an orally active corticotropin releasing factor-1 (CRF-1) receptor antagonist.

The design, synthesis, and structure-activity relationships of a novel series of pyrazines, acting as corticotropin releasing factor-1 (CRF-1) receptor antagonists, are described. Synthetic methodologies were developed to prepare a number of substituted pyrazine cores utilizing regioselective halogenation and chemoselective derivatization. Noteworthy, an efficient 5-step synthesis was developed for the lead compound 59 (NGD 98-2), which required no chromatography. Compound 59 was characterized as an orally bioavailable, brain penetrant, and highly selective CRF-1 receptor antagonist. Occupancy of rat brain CRF-1 receptors was quantified using ex vivo receptor occupancy assays, using both brain tissue homogenates as well as brain slices receptor autoradiography. Behaviorally, oral administration of 59 significantly antagonized CRF-induced locomotor activity at doses as low as 10 mg/kg and dose-dependently reduced the restraint stress-induced ACTH increases.

The dopamine D(2) receptor partial agonist aplindore improves motor deficits in MPTP-treated common marmosets alone and combined with L-dopa.

Dopamine replacement therapy in Parkinson's disease (PD) using L-dopa is invariably associated with a loss of drug efficacy ("wearing off") and the onset of dyskinesia. The use of dopamine receptor partial agonists might improve therapeutic benefit without increased dyskinesia expression but may antagonise the effects of L-dopa. We now examine the effects of the novel high affinity, dopamine D(2) receptor partial agonist, aplindore alone and in combination with L-dopa in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated common marmoset. In non-dyskinetic MPTP treated animals, aplindore (0.05-1.0 mg/kg p.o.) produced a dose-dependent reversal of motor disability and an increase in locomotor activity that was maximal at doses of 0.2 mg/kg and above. In animals previously exposed to L: -dopa to induce dyskinesia, escalating and repeated dosing of aplindore (0.05-0.5 mg/kg p.o.) produced a sustained, dose-related improvement in motor disability and an increase in locomotor activity. The effects were maximal at a dose of 0.1 mg/kg and above and not different from those produced by L-dopa (12.5 mg/kg plus carbidopa 12.5 mg/kg p.o.). Aplindore administration also led to dose-dependent expression of dyskinesia but at 0.1 mg/kg, this was significantly less intense than that produced by L-dopa. Administration of aplindore (1.0 mg/kg p.o.) in combination with L-dopa (2.5 mg/kg plus carbidopa 12.5 mg/kg p.o.) did not inhibit the reversal of motor deficits but improved motor disability and increased both locomotor activity and dyskinesia expression equivalent to that produced by L-dopa (12.5 mg/kg plus carbidopa 12.5 mg/kg p.o.). These data suggest that dopamine receptor partial agonists would be effective in the treatment of Parkinson's disease and would not inhibit the beneficial actions of L-dopa.

2-Arylpyrimidines: novel CRF-1 receptor antagonists.

The design, synthesis and structure-activity relationship studies of a novel series of CRF-1 receptor antagonists, the 2-arylpyrimidines, are described. The effects of substitution on the aromatic ring and the pyrimidine core on CRF-1 receptor binding were investigated. A number of compounds with K(i) values below 10 nM and lipophilicity in a minimally acceptable range for a CNS drug (cLogP<5) were discovered.

The design, synthesis and structure-activity relationships of 1-aryl-4-aminoalkylisoquinolines: a novel series of CRF-1 receptor antagonists.

The design, synthesis and structure-activity relationships of a novel series of CRF-1 receptor antagonist, the 1-aryl-4-alkylaminoisoquinolines, is described. The effects of substitution on the aromatic ring, the amino group and the isoquinoline core on CRF-1 receptor binding were investigated.

Indoline and piperazine containing derivatives as a novel class of mixed D(2)/D(4) receptor antagonists. Part 2: asymmetric synthesis and biological evaluation.

A series of chiral benzylpiperazinyl-1-(2,3-dihydro-indol-1-yl)ethanone derivatives were prepared and examined for their affinity at dopamine D(2) and D(4) receptors. Three compounds having D(2)/D(4) affinity ratios approximating that found for the atypical neuroleptic clozapine were further evaluated in behavioral tests of antipsychotic efficacy and motor side effects.

A multicenter, randomized, double-blind, placebo-controlled trial of adjuvant methotrexate treatment for giant cell arteritis.

OBJECTIVE: To evaluate treatment with methotrexate (MTX) in patients with newly diagnosed giant cell arteritis (GCA) to determine if MTX reduces GCA relapses and cumulative corticosteroid (CS) requirements and diminishes disease- and treatment-related morbidity. METHODS: This was a multicenter, randomized, double-blind study. Over 4 years, 16 centers from the International Network for the Study of Systemic Vasculitides enrolled patients with unequivocal GCA. The initial treatment was 1 mg/kg/day (