Pharmacokinetics and safety of TBAJ-876, a novel antimycobacterial diarylquinoline, in healthy subjects.

TBAJ-876, a second-generation diarylquinoline with greater antimycobacterial activity and a potentially better safety profile compared with bedaquiline, is under development for the treatment of drug-susceptible and drug-resistant tuberculosis (TB). A phase 1, first-in-human study of TBAJ-876, comprising a single-ascending dose (SAD) part including a food effect cohort, a multiple-ascending dose (MAD) part, and a relative bioavailability part of tablets versus oral suspension, was conducted on 137 healthy adults. A drug-drug interaction study was conducted on 28 healthy adults to evaluate the effects of TBAJ-876 on a cytochrome P450 3A4 substrate (midazolam) and a P-glycoprotein substrate (digoxin). TBAJ-876 was well-tolerated at single doses up to 800 mg and multiple doses up to 200 mg for 14 days. No deaths or serious adverse events occurred. No episodes of clinically significant prolongation of the QTc interval were observed. TBAJ-876 exposures were dose proportional in the SAD and MAD studies. TBAJ-876 exhibited multicompartmental pharmacokinetics (PK) with a long terminal half-life yielding quantifiable concentrations up to the longest follow-up of 10 weeks after a single dose and resulting in accumulation with multiple dosing. In the fed state, TBAJ-876 exposures approximately doubled with the tablet formulation, whereas M3 metabolite exposures decreased by approximately 20%. The relative bioavailability of TBAJ-876 was similar between tablets and the oral suspension at 100-mg doses. With co-administration of TBAJ-876, the AUC0-inf of midazolam was unchanged and the Cmax was reduced by 14%; the AUC0-last of digoxin was increased by 51%, and the Cmax was increased by 18%. These results support further investigation of TBAJ-876 for the treatment of tuberculosis.

Fed- and Fasted-State Performance of Pretomanid Amorphous Solid Dispersions Formulated with an Enteric Polymer.

Weakly acid polymers with pH-responsive solubility are being used with increasing frequency in amorphous solid dispersion (ASD) formulations of drugs with low aqueous solubility. However, drug release and crystallization in a pH environment where the polymer is insoluble are not well understood. The aim of the current study was to develop ASD formulations optimized for release and supersaturation longevity of a rapidly crystallizing drug, pretomanid (PTM), and to evaluate a subset of these formulations in vivo. Following screening of several polymers for their ability to inhibit crystallization, hypromellose acetate succinate HF grade (HPMCAS-HF; HF) was selected to prepare PTM ASDs. In vitro release studies were conducted in simulated fasted- and fed-state media. Drug crystallization in ASDs following exposure to dissolution media was evaluated by powder X-ray diffraction, scanning electron microscopy, and polarized light microscopy. In vivo oral pharmacokinetic evaluation was conducted in male cynomolgus monkeys (n = 4) given 30 mg PTM under both fasted and fed conditions in a crossover design. Three HPMCAS-based ASDs of PTM were selected for fasted-state animal studies based on their in vitro release performance. Enhanced bioavailability was observed for each of these formulations relative to the reference product that contained crystalline drug. The 20% drug loading PTM-HF ASD gave the best performance in the fasted state, with subsequent dosing in the fed state. Interestingly, while food improved drug absorption of the crystalline reference product, the exposure of the ASD formulation was negatively impacted. The failure of the HPMCAS-HF ASD to enhance absorption in the fed state was hypothesized to result from poor release in the reduced pH intestinal environment resulting from the fed state. In vitro experiments confirmed a reduced release rate under lower pH conditions, which was attributed to reduced polymer solubility and an enhanced crystallization tendency of the drug. These findings emphasize the limitations of in vitro assessment of ASD performance using standardized media conditions. Future studies are needed for improved understanding of food effects on ASD release and how this variability can be captured by in vitro testing methodologies for better prediction of in vivo outcomes, in particular for ASDs formulated with enteric polymers.

International Guideline Adherence in Girls with Turner Syndrome: Multiple Subspecialty Clinics Versus Coordinated Multidisciplinary Clinic.

OBJECTIVE: To evaluate the 2016 Cincinnati International Turner syndrome (TS) consensus guideline adherence within our pediatric tertiary referral center and determine if patients managed in our single-day, coordinated multidisciplinary clinic (MDC) format showed superior adherence rates when compared with those managed outside our MDC format. METHODS: We retrospectively reviewed the charts of patients with TS followed at our center from January 1, 2018, to April 30, 2020. The individual and overall adherence rates of 9 age-appropriate screening recommendations were evaluated along with rates of TS comorbidities within our cohort. RESULTS: A total of 111 girls met the study criteria. Sixty-eight were managed in the MDC and 43 were managed outside the MDC. Only 42% of all the girls met all 9 evaluated age-appropriate screening recommendations, of 47 girls, 33 (70%) were managed in MDC compared with 14 (30%) who were managed in the non-MDC. Girls managed in the MDC had higher screening adherence rates versus non-MDC girls for 7 of the 9 evaluated screenings with especially large differences noted for thyroid stimulating hormone (95% vs 78%, P = .034), auditory evaluation (97% vs 65%, P < .001), and HgA1c levels (82% vs 54%, P = .014). CONCLUSION: Girls managed in the MDC format showed higher rates of screening guideline adherence, both overall and with multiple specific screening tests, than those managed outside the MDC format. Overall guideline adherence remained low (42%), highlighting the need for continued optimization and improvement in guideline adherence in this unique subset of the population.

Evaluation of in vitro absorption, distribution, metabolism, and excretion and assessment of drug-drug interaction of rucaparib, an orally potent poly(ADP-ribose) polymerase inhibitor.

1. The absorption, distribution, metabolism, elimination, and drug-drug interaction (DDI) potential of the poly(ADP-ribose) polymerase (PARP) inhibitor rucaparib was characterised in vitro.2. Rucaparib showed moderate cellular permeability, moderate human plasma protein binding (70.2%), and slow metabolism in human liver microsomes (HLMs). In HLMs, cytochrome P450 (CYP) 1A2 and CYP3A contributed to the metabolism of rucaparib to its major metabolite M324 with estimated fractions of metabolism catalysed by CYP (fm,CYP) of 0.27 and 0.64, respectively. Rucaparib reversibly inhibited CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3As (IC50, 3.55, 12.9, 5.42, 41.6, and 17.2-22.9 µM [2 substrates], respectively), but not CYP2B6 or CYP2C8 (>190 µM). No time-dependent inhibition of any CYP was observed. In cultured human hepatocytes, rucaparib showed concentration-dependent induction of CYP1A2 mRNA and downregulation of CYP3A4 and CYP2B6 mRNA. In transfected cells expressing drug transporters, rucaparib was a substrate for P-gp and BCRP, but not for OATP1B1, OATP1B3, OAT1, OAT3, or OCT2. Rucaparib inhibited P-gp and BCRP (IC50, 169 and 55 µM, respectively) and slightly inhibited OATP1B1, OATP1B3, OAT1, and OAT3 (66%, 58%, 58%, and 42% inhibition, respectively) at 300 µM. Rucaparib inhibited OCT1, OCT2, MATE1, and MATE2-K (IC50, 4.3, 31, 0.63, and 0.19 µM, respectively).3. DDI risk assessment using static models suggested potential CYP-related DDIs, with rucaparib as a perpetrator. Caution is advised when co-administering rucaparib with sensitive substrates of MATEs, OCT1, and OCT2.

Rociletinib in EGFR-mutated non-small-cell lung cancer.

BACKGROUND: Non-small-cell lung cancer (NSCLC) with a mutation in the gene encoding epidermal growth factor receptor (EGFR) is sensitive to approved EGFR inhibitors, but resistance develops, mediated by the T790M EGFR mutation in most cases. Rociletinib (CO-1686) is an EGFR inhibitor active in preclinical models of EGFR-mutated NSCLC with or without T790M. METHODS: In this phase 1-2 study, we administered rociletinib to patients with EGFR-mutated NSCLC who had disease progression during previous treatment with an existing EGFR inhibitor. In the expansion (phase 2) part of the study, patients with T790M-positive disease received rociletinib at a dose of 500 mg twice daily, 625 mg twice daily, or 750 mg twice daily. Key objectives were assessment of safety, side-effect profile, pharmacokinetics, and preliminary antitumor activity of rociletinib. Tumor biopsies to identify T790M were performed during screening. Treatment was administered in continuous 21-day cycles. RESULTS: A total of 130 patients were enrolled. The first 57 patients to be enrolled received the free-base form of rociletinib (150 mg once daily to 900 mg twice daily). The remaining patients received the hydrogen bromide salt (HBr) form (500 mg twice daily to 1000 mg twice daily). A maximum tolerated dose (the highest dose associated with a rate of dose-limiting toxic effects of less than 33%) was not identified. The only common dose-limiting adverse event was hyperglycemia. In an efficacy analysis that included patients who received free-base rociletinib at a dose of 900 mg twice daily or the HBr form at any dose, the objective response rate among the 46 patients with T790M-positive disease who could be evaluated was 59% (95% confidence interval [CI], 45 to 73), and the rate among the 17 patients with T790M-negative disease who could be evaluated was 29% (95% CI, 8 to 51). CONCLUSIONS: Rociletinib was active in patients with EGFR-mutated NSCLC associated with the T790M resistance mutation. (Funded by Clovis Oncology; ClinicalTrials.gov number, NCT01526928.).

A phase I study of intravenous and oral rucaparib in combination with chemotherapy in patients with advanced solid tumours.

BACKGROUND: This study evaluated safety, pharmacokinetics, and clinical activity of intravenous and oral rucaparib, a poly(ADP-ribose) polymerase inhibitor, combined with chemotherapy in patients with advanced solid tumours. METHODS: Initially, patients received escalating doses of intravenous rucaparib combined with carboplatin, carboplatin/paclitaxel, cisplatin/pemetrexed, or epirubicin/cyclophosphamide. Subsequently, the study was amended to focus on oral rucaparib (once daily, days 1-14) combined with carboplatin (day 1) in 21-day cycles. Dose-limiting toxicities (DLTs) were assessed in cycle 1 and safety in all cycles. RESULTS: Eighty-five patients were enrolled (22 breast, 15 ovarian/peritoneal, and 48 other primary cancers), with a median of three prior therapies (range, 1-7). Neutropenia (27.1%) and thrombocytopenia (18.8%) were the most common grade ⩾3 toxicities across combinations and were DLTs with the oral rucaparib/carboplatin combination. Maximum tolerated dose for the combination was 240 mg per day oral rucaparib and carboplatin area under the curve 5 mg ml-1 min-1. Oral rucaparib demonstrated dose-proportional kinetics, a long half-life (≈17 h), and good bioavailability (36%). Pharmacokinetics were unchanged by carboplatin coadministration. The rucaparib/carboplatin combination had radiologic antitumour activity, primarily in BRCA1- or BRCA2-mutated breast and ovarian/peritoneal cancers. CONCLUSIONS: Oral rucaparib can be safely combined with a clinically relevant dose of carboplatin in patients with advanced solid tumours (Trial registration ID: NCT01009190).

Implementing motivational interviewing in a pediatric hospital.

Motivational Interviewing is a collaborative style of communication designed to strengthen a person's own motivation and commitment to change. We report on our ongoing efforts to implement motivational interviewing to address health behavior change among several patient populations in our pediatric hospital, including sexual risk reduction among adolescents, increased self-care for patients with spina bifida, increased adherence for adolescents with Type 1 diabetes, and facilitation with transition from pediatric to adult care among gastroenterology patients.

SNARE-ing the Reason for Post-Cardiac Surgery Critical Illness-Related Corticosteroid Insufficiency.

Critical illness-related corticosteroid insufficiency (CIRCI) can cause hemodynamic instability in neonates after congenital heart surgery with manifestations that increase morbidity and potential mortality. We retrospectively reviewed neonates who underwent cardiac surgery between August 2018 and July 2020 at a freestanding children's hospital, had next-generation sequencing performed, and had their cortisol levels drawn as standard clinical care after cardiac surgery. The groups were defined as CIRCI (with a cortisol level ≤ 4.5 mcg/dL) and non-CIRCI (level > 4.5 mcg/dL). The CIRCI group (n = 8) had a 100% incidence of heterozygous gene mutation on STX1A with splicing or loss of function, and this mutation was not found in the non-CIRCI group (n = 8). Additional gene mutations were found in the CIRCI group on RAB6A, ABCA3, SIDT2, and LILRB3, with no incidence in the non-CIRCI group. Three additional mutations were found across the CIRCI group in INPPL1 and FAM189A2 (both splicing and missense), with 12-25% of patients in the non-CIRCI group also displaying these mutations. Novel genetic abnormalities were seen in neonates with symptoms of CIRCI with potential cardiac implications from a gene mutation for STX1A. Compounding effects of additional gene mutations need to be confirmed and explored for potential predisposition to hemodynamic instability during times of stress.

Recognizing Complications in Youth With Diabetes Admitted With Diabetic Ketoacidosis Versus Hyperglycemic Hyperosmolar State.

INTRODUCTION: We compare in-hospital complications in youth with isolated diabetic ketoacidosis (DKA) to youth with hyperosmolarity. METHOD: We reviewed medical records of youth (1-20 years) admitted over two years with DKA, hyperglycemic hyperosmolar state (HHS), and hyperosmolar DKA. We evaluated outcomes, including hospital length of stay, altered mental status (AMS), and acute kidney injury (AKI). RESULTS: Of 369 admissions, 334 had isolated DKA, 32 had hyperosmolar DKA, and three had isolated HHS. Hyperosmolar youth had longer length of stay, larger initial fluid boluses, more frequent pediatric intensive care unit admissions, and increased risk of AKI and AMS. The odds of AKI were positively associated with serum osmolality and negatively associated with new-onset diabetes mellitus (DM) compared with established DM. CONCLUSIONS: In youth with DM, hyperosmolarity increases acute complications compared with isolated DKA. Larger-scale studies are needed to identify ways to prevent acute complications in youth experiencing hyperglycemic emergencies.

A novel class of 3-(phenoxy-phenyl-methyl)-pyrrolidines as potent and balanced norepinephrine and serotonin reuptake inhibitors: synthesis and structure-activity relationships.

A series of 3-(phenoxy-phenyl-methyl)-pyrrolidine analogues were discovered to be potent and balanced norepinephrine (NE) and serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors. Several of these compounds were identified to have suitable in vitro pharmacokinetic properties for an orally dosed and CNS-targeted drug. Compound 39b, in particular, was identified as a potent NET and SERT reuptake inhibitor (NSRI) with minimal off-target activity and demonstrated robust efficacy in the spinal nerve ligation model of pain behavior.

Hyperinsulinemic Hypoglycemia and Growth Hormone Deficiency Secondary to 20p11 Deletion.

Hypoglycemia is concerning for neurological complications in infants and children. Determining the cause of hypoglycemia is essential in providing appropriate treatment. Hyperinsulinism and growth hormone deficiency are known causes of hypoglycemia but are not commonly found together. We report a 4-month-old boy who presented with severe hypoglycemia and was found to have both hyperinsulinism and growth hormone deficiency. Treatment with both recombinant human growth hormone and diazoxide led to blood glucose normalization. Subsequently, he was found to have a genetic diagnosis of 20p11.22p11.21 deletion. 20p11 deletions have been associated with hypopituitarism, most commonly seen in growth hormone deficiency causing hypoglycemia. This case is one of a few to report hyperinsulinism as a manifestation of this deletion.

AZD-3043: a novel, metabolically labile sedative-hypnotic agent with rapid and predictable emergence from hypnosis.

BACKGROUND: Propofol can be associated with delayed awakening after prolonged infusion. The aim of this study was to characterize the preclinical pharmacology of AZD-3043, a positive allosteric modulator of the γ-aminobutyric acid type A (GABA(A)) receptor containing a metabolically labile ester moiety. The authors postulated that its metabolic pathway would result in a short-acting clinical profile. METHODS: The effects of AZD-3043, propofol, and propanidid were studied on GABA(A) receptor-mediated chloride currents in embryonic rat cortical neurons. Radioligand binding studies were also performed. The in vitro stability of AZD-3043 in whole blood and liver microsomes was evaluated. The duration of the loss of righting reflex and effects on the electroencephalograph evoked by bolus or infusion intravenous administration were assessed in rats. A mixed-effects kinetic-dynamic model using minipigs permitted exploration of the clinical pharmacology of AZD-3043. RESULTS: AZD-3043 potentiated GABA(A) receptor-mediated chloride currents and inhibited [(35)S]tert-butylbicyclophosphorothionate binding to GABA(A) receptors. AZD-3043 was rapidly hydrolyzed in liver microsomes from humans and animals. AZD-3043 produced hypnosis and electroencephalograph depression in rats. Compared with propofol, AZD-3043 was shorter acting in rats and pigs. Computer simulation using the porcine kinetic-dynamic model demonstrated that AZD-3043 has very short 50 and 80% decrement times independent of infusion duration. CONCLUSIONS: AZD-3043 is a positive allosteric modulator of the GABA(A) receptor in vitro and a sedative-hypnotic agent in vivo. The esterase dependent metabolic pathway results in rapid clearance and short duration of action even for long infusions. AZD-3043 may have clinical potential as a sedative-hypnotic agent with rapid and predictable recovery.

A retrospective review of pituitary MRI findings in children on growth hormone therapy.

BACKGROUND: Patients with congenital hypopituitarism might have the classic triad of pituitary stalk interruption syndrome, which consists of: (1) an interrupted or thin pituitarys talk, (2) an absent or ectopic posterior pituitary (EPP), and (3) anterior pituitary hypoplasia or aplasia. OBJECTIVE: To examine the relationship between pituitary anatomy and the degree of hormonal dysfunction. MATERIALS AND METHODS: This study involved a retrospective review of MRI findings in all children diagnosed with congenital growth hormone deficiency from 1988 to 2010 at a tertiary-level pediatric hospital. RESULTS: Of the 52 MRIs reviewed in 52 children, 26 children had normal pituitary anatomy and 26 had one or more elements of the classic triad. Fourteen of fifteen children with multiple pituitary hormone deficiencies had structural anomalies on MRI. Twelve of 37 children with isolated growth hormone deficiency had an abnormal MRI. CONCLUSION: Children with multiple pituitary hormone deficiencies were more likely to have the classic triad than children with isolated growth hormone deficiency. A normal MRI was the most common finding in children with isolated growth hormone deficiency.

Hyperglycemic hyperosmolar syndrome at the onset of type 2 diabetes mellitus in an adolescent male.

Hyperglycemic hyperosmolar state (HHS) is rare in the paediatric population. The diagnosis and management of HHS presents a challenge in paediatric patients who may present with a mixed picture of HHS and diabetic ketoacidosis (DKA).A 15-year-old obese African American male was brought to the emergency department following a two-day history of feeling unwell. The patient was obtunded, hypotensive and tachypneic. Initial investigations revealed the following: pH 6.97 (normal 7.35 to 7.41), HCO(3) (-) 5 mEq/L (normal 20 mEq/L to 25 mEq/L), glucose 90.9 mmol/L (normal 3.4 mmol/L to 6.3 mmol/L), serum osmolality 454 mOsm/kg (normal 275 mOsm/kg to 295 mOsm/kg), Na(+) 141 mEq/L (normal 135 mEq/L to 145 mEq/L), corrected Na(+) 165 mEq/L, K(+) 8.4 mEq/L (normal 3.5 mEq/L to 5.0 mEq/L), urinalysis revealed 1+ ketones and 4+ glucose. The patient's clinical course was complicated by severe hyperkalemia, acute renal failure, refractory status epilepticus, rhabdomyolysis, pancreatitis and hypertension.The present case emphasizes the complexity of managing patients with a mixed DKA/HHS presentation and associated morbidities. It is very important to disseminate and implement screening guidelines for type 2 diabetes mellitus, so as to prevent this potentially devastating complication.

An interspecies extrapolation of the pharmacokinetics of telavancin, a rapidly bactericidal, concentration-dependent antibiotic.

Telavancin is an intravenous lipoglycopeptide antibiotic active against many Gram-positive pathogens via inhibition of bacterial cell wall synthesis and disruption of bacterial membrane function. Non-compartmental pharmacokinetic parameters of telavancin (clearance [Cl], steady-state volume of distribution [Vss], area under the concentration curve [AUC], and elimination half-life [t(1/2)]) were determined for five preclinical species (mice, rats, rabbits, dogs, and monkeys). Interspecies scaling was applied to predict the corresponding parameters in humans and compare retrospectively with observed values. Plasma concentrations of single doses of telavancin declined monoexponentially in all species with half-lives between 1.2 and 2.4 h. The pharmacokinetics of telavancin was demonstrated to be dose-proportional in rabbits and gender-independent in monkeys. Application of the simple allometric equation (Y = aW(b)) resulted in a good correlation between predicted and observed values of Vss in humans. Application of a modified allometric equation that includes brain weight (Cl × BW = aW(b)) resulted in a good correlation between predicted and observed values of Cl, AUC, and t(1/2) in humans. These data suggest that interspecies scaling may be useful to predict pharmacokinetic parameters of telavancin in humans.

The Severity of Growth Hormone Deficiency Does Not Predict the Presence or Absence of Brain Magnetic Resonance Imaging Abnormalities - A Retrospective Review.

BACKGROUND: The Growth Hormone Research Society recommends that all patients diagnosed with growth hormone deficiency (GHD) should undergo brain magnetic resonance imaging (MRI). This is still a point of controversy in patients with mild GHD, as the level of peak growth-hormone (GH) as a predictor of brain MRI abnormality has not yet been established. The objective of this study was to determine if peak GH level, determined by stimulation tests, can predict the presence or absence of brain MRI abnormality. METHODS: This study was a retrospective chart review from 2008-2015. Patients were aged 2-18 years, and had growth failure and GHD as determined by stimulation test. Patients with history of brain tumour, chemotherapy and brain surgery, prior to the diagnosis of GHD, were excluded. RESULTS: A total of 386 patients were included. GH values (mild versus severe GHD) did not predict brain MRI abnormality with any agent (clonidine: p=0.07; arginine: p=0.17; glucagon: p=0.42). Abnormal MRI was apparent in 19.2% of the patients with mild GHD and 24.8% of the patients with severe GHD (p=0.17). Severe MRI abnormality was seen in 6.1% of the patients with mild GHD and 15.0% of the patients with severe GHD (p=0.009). CONCLUSIONS: The severity of GHD based on peak GH levels on stimulation tests did not predict the presence or absence of brain MRI abnormalities in our study population; however, severe GHD was more strongly associated with severe brain MRI abnormalities. Based on these results we recommend obtaining brain MRI in all patients with GHD.

Variations in Morning Serum Cortisol Levels Based on Sex and Pubertal Status.

INTRODUCTION: Patients with suspected adrenal insufficiency undergo screening with a serum morning cortisol level and confirmatory testing with an adrenocorticotropic hormone (ACTH) stimulation test. However, much of the data collected to determine appropriate values for morning cortisol levels are derived from adult populations and may not accurately represent pediatric physiology. The purpose of this study was to evaluate the mean morning cortisol level in the pediatric population based on pubertal status and sex in order to better understand such influences on laboratory evaluation of adrenal insufficiency. METHODS: A retrospective chart review was conducted using electronic medical records of patients seen at Children's Mercy Kansas City from 11/01/2007 to 11/01/2017. Patients between 2 and 18 years of age who had pubertal staging assessed by a pediatric endocrinologist and confirmed adrenal sufficiency by high-dose ACTH stimulation testing were included. Two-sample Wilcoxon rank sum (Mann-Whitney) tests or t tests were used to compare morning cortisol levels between females and males - both independent of Tanner stage and by Tanner stage. Multivariable regression models were used to evaluate associations among covariates on two outcomes: morning cortisol levels and peak cortisol values with ACTH stimulation. RESULTS: Morning cortisol levels were greater in females than males independent of Tanner staging (p = 0.0054) and also in Tanner stage 1 (p = 0.0042). No differences in mean morning cortisol levels between Tanner stage 2-5 females and males were found (p = 0.4652). Morning cortisol levels were not significantly different between Tanner 1 patients and Tanner 2-5 patients independent of sex (p = 0.0575). Sex was predictive of serum morning cortisol levels (p = 0.015), and morning cortisol levels were predictive of peak cortisol levels during ACTH stimulation testing (p < 0.001). CONCLUSIONS: These data suggest that different normative cortisol values may need to be established for pediatric females and males, and by pubertal status. Larger prospective studies are needed to evaluate the role of sex and pubertal status in identifying adrenal insufficiency in the -pediatric population.

A New Paediatric Diabetes Knowledge Test - M-WIKAD Development and Factor Analysis.

Purpose: The purpose of this study was to develop a measure of type 1 diabetes mellitus (T1DM) knowledge that is aimed at youth and is based on contemporary management standards. Methods: An 88-item test was derived from the American Association of Diabetes Educators 7 Self-Care Behaviors. Results: A multidisciplinary team selected the best 49 items which were piloted in a sample of 119 youths (59 males, aged 12-18, having a mean ± standard deviation glycated haemoglobin (A1C) of 9.9%±1.80 (84.7±19.7 mmol/mol). A minimum absolute point-biserial correlation coefficient of 0.250 was used to choose 49 items from the original 88 questions. Categorical principal component analysis was then used to identify the best factor analytical model that consisted of five factors composed of 19 items. These five factors explained 57% of item variances. Factors were associated with the latent variables: advanced problem-solving, hypoglycaemia prevention and management, taking insulin/medication administration, daily management and healthy active living. Conclusion: A new T1D knowledge test for youth was refined from 88 to 49 questions based on expert opinion and empirical test construction. The instrument was then refined to 19 items based on exploratory factor analysis. Future goals are to validate this factor model with another cohort and confirm concurrent validity based on youth's glycated haemoglobin and adherence behaviours. Our new T1DM knowledge measure initially appears valid and promising as a new clinical and research tool.

Pharmacokinetic Study of Rucaparib in Patients With Advanced Solid Tumors.

The phase 1-2 study CO-338-010 (Study 10; NCT01482715) is evaluating single-agent rucaparib, a poly(ADP-ribose) polymerase inhibitor, administered orally to patients with an advanced solid tumor. In the dose escalation phase (Part 1), we characterized the single-dose and steady-state pharmacokinetic profiles of rucaparib administered once daily (QD; dose range, 40-500 mg; n = 16) or twice daily (BID; dose range, 240-840 mg; n = 30). Across all dosing schedules examined, the plasma exposure of rucaparib was approximately dose proportional; half-life was approximately 17 hours, and median time to maximum concentration (tmax ) ranged from 1.5 to 6.0 hours after a single dose and 1.5 to 4.0 hours following repeated dosing. The steady-state accumulation ratio ranged from 1.60 to 2.33 following QD dosing and 1.47 to 5.44 following BID dosing. No effect of food on rucaparib pharmacokinetics was observed with a single dose of 40 mg (n = 3) or 300 mg (n = 6). In a phase 2 portion of the study (Part 3), the pharmacokinetic profile of rucaparib was further evaluated at the recommended phase 2 dose of 600 mg BID (n = 26). The mean (coefficient of variation) steady-state maximum concentration (Cmax ) and area under the concentration-time curve from time zero to 12 hours (AUC0-12h ) were 1940 ng/mL (54%) and 16 900 ng ⋅ h/mL (54%), respectively. A high-fat meal moderately increased rucaparib exposure. The fed-to-fasted geometric mean ratios (90% confidence interval [CI]) for AUC0-24h and Cmax were 138% (117%-162%) and 120% (99.1%-146%); the median (90%CI) tmax delay was 2.5 (0.5-4.4) hours.

Pharmacological analysis of the interaction of antimuscarinic drugs at M(2) and M(3) muscarinic receptors in vivo using the pithed rat assay.

Muscarinic receptor antagonists form the mainstay of the therapeutic options for airway, bladder, and gastrointestinal smooth muscle disorders. Both M(2) and M(3) muscarinic receptors are involved in mediating smooth muscle contractility, although the relative functional contribution of each subtype, especially in the disease state, is unclear. Because the potency and selectivity of compounds for a given receptor in an in vivo setting can be dissimilar to that observed in an in vitro system, we developed an in vivo assay to simultaneously determine the absolute potency and selectivity of muscarinic receptor antagonists at M(2) and M(3) receptors using the pithed rat. Methacholine (MCh)-induced bradycardia and depressor responses were used as surrogate functional endpoints for M(2) and M(3) receptor activation, respectively. The influence of the muscarinic antagonists, tolterodine, oxybutynin, darifenacin, Ro 320-6206, solifenacin, or tiotropium on the MCh-induced responses were studied. The estimated DR(10) values (dose producing a tenfold shift in the MCh curve) of tolterodine, oxybutynin, darifenacin, Ro 320-6206, solifenacin, and tiotropium for the M(2) muscarinic receptor-mediated bradycardia were 0.22, 1.18, approximately 2.6, 0.025, 0.40, and 0.0026 mg/kg, respectively, and 0.14, 0.18, 0.11, 3.0, 0.18, and 0.0017 mg/kg, respectively, for the M(3) muscarinic receptor-mediated depressor response. In a separate set of experiments, a single intravenous dose of tiotropium was administered before a MCh curve at 1, 3, 6, or 9 h to determine if tiotropium exhibited time-dependent selectivity for the M(3) receptor as has been reported from in vitro studies. The results indicate a slight preference of tiotropium for the M(3) receptor at later time points. The pithed rat assay may serve useful for elucidating the functional contribution of M(2) and M(3) receptors to the in vivo pharmacological effects of antagonists in disease animal models.