UX007 for the treatment of long chain-fatty acid oxidation disorders: Safety and efficacy in children and adults following 24weeks of treatment

BACKGROUND

Long-chain fatty acid oxidation disorders (LC-FAOD) lead to accumulation of high concentrations of potentially toxic fatty acid intermediates. Newborn screening and early intervention have reduced mortality, but most patients continue to experience frequent hospitalizations and significant morbidity despite treatment. The deficient energy state can cause serious liver, muscle, and heart disease, and may be associated with an increased risk of sudden death. Triheptanoin is a medium odd-chain fatty acid. Anaplerotic metabolites of triheptanoin have the potential to replace deficient tricarboxylic acid (TCA) cycle intermediates, resulting in net glucose production as a novel energy source for the treatment of LC-FAOD.

STUDY DESIGN

A single-arm, open-label, multicenter Phase 2 safety and efficacy study evaluated patients with severe LC-FAOD evidenced by ongoing related musculoskeletal, cardiac, and/or hepatic events despite treatment. After a four-week run-in on current regimen, investigational triheptanoin (UX007) was titrated to a target dose of 25-35% of total daily caloric intake. Patients were evaluated on several age/condition-eligible endpoints, including submaximal exercise tests to assess muscle function/endurance (12-minute walk test; 12MWT) and exercise tolerance (cycle ergometry), and health related quality of life (HR-QoL). Results through 24weeks of treatment are presented; total study duration is 78weeks.

RESULTS

Twenty-nine patients (0.8 to 58years) were enrolled; most qualified based on severe musculoskeletal disease. Twenty-five patients (86%) completed the 24-week treatment period. At Week 18, eligible patients (n=8) demonstrated a 28% increase (LS mean=+181.9 meters; p=0.087) from baseline (673.4meters) in 12MWT distance. At Week 24, eligible patients (n=7) showed a 60% increase in watts generated (LS mean=+409.3W; p=0.149) over baseline (744.6W) for the exercise tolerance test. Improvements in exercise tests were supported by significant improvements from baseline in the adult (n=5) self-reported SF-12v2 physical component summary score (LS mean=+8.9; p<0.001). No difference from baseline was seen in pediatric parent-reported (n=5) scores (SF-10) at Week 24. Eighteen patients (62%) had treatment-related adverse events, predominantly gastrointestinal (55%), mild-to-moderate in severity, similar to that seen with prior treatment with medium chain triglyceride (MCT) oil. One patient experienced a treatment-related serious adverse event of gastroenteritis. One patient discontinued from study due to diarrhea of moderate severity; the majority of patients (25/29; 86%) elected to continue treatment in the extension period.

CONCLUSIONS

In patients with severe LC-FAOD, UX007 interim study results demonstrated improved exercise endurance and tolerance, and were associated with positive changes in self-reported HR-QoL.

Mitigation of Acetylcholine Esterase Activity in the 1,7-Diazacarbazole Series of Inhibitors of Checkpoint Kinase 1

Checkpoint kinase 1 (ChK1) plays a key role in the DNA damage response, facilitating cell-cycle arrest to provide sufficient time for lesion repair. This leads to the hypothesis that inhibition of ChK1 might enhance the effectiveness of DNA-damaging therapies in the treatment of cancer. Lead compound 1 (GNE-783), the prototype of the 1,7-diazacarbazole class of ChK1 inhibitors, was found to be a highly potent inhibitor of acetylcholine esterase (AChE) and unsuitable for development. A campaign of analogue synthesis established SAR delineating ChK1 and AChE activities and allowing identification of new leads with improved profiles. In silico docking using a model of AChE permitted rationalization of the observed SAR. Compounds 19 (GNE-900) and 30 (GNE-145) were identified as selective, orally bioavailable ChK1 inhibitors offering excellent in vitro potency with significantly reduced AChE activity. In combination with gemcitabine, these compounds demonstrate an in vivo pharmacodynamic effect and are efficacious in a mouse p53 mutant xenograft model.

Minor Structural Change to Tertiary Sulfonamide RORc Ligands Led to Opposite Mechanisms of Action

A minor structural change to tertiary sulfonamide RORc ligands led to distinct mechanisms of action. Co-crystal structures of two compounds revealed mechanistically consistent protein conformational changes. Optimized phenylsulfonamides were identified as RORc agonists while benzylsulfonamides exhibited potent inverse agonist activity. Compounds behaving as agonists in our biochemical assay also gave rise to an increased production of IL-17 in human PBMCs whereas inverse agonists led to significant suppression of IL-17 under the same assay conditions. The most potent inverse agonist compound showed >180-fold selectivity over the ROR isoforms as well as all other nuclear receptors that were profiled.

A randomized, placebo-controlled, double-blind study of sapropterin to treat ADHD symptoms and executive function impairment in children and adults with sapropterin-responsive phenylketonuria

Symptoms of attention deficit-hyperactivity disorder (ADHD), particularly inattention, and impairments in executive functioning have been reported in early and continuously treated children, adolescents, and adults with phenylketonuria (PKU). In addition, higher blood phenylalanine (Phe) levels have been correlated with the presence of ADHD symptoms and executive functioning impairment. The placebo-controlled PKU ASCEND study evaluated the effects of sapropterin therapy on PKU-associated symptoms of ADHD and executive and global functioning in individuals who had a therapeutic blood Phe response to sapropterin therapy. The presence of ADHD inattentive symptoms and executive functioning deficits was confirmed in this large cohort of 206 children and adults with PKU, of whom 118 responded to sapropterin therapy. In the 38 individuals with sapropterin-responsive PKU and ADHD symptoms at baseline, sapropterin therapy resulted in a significant improvement in ADHD inattentive symptoms in the first 4 weeks of treatment, and improvements were maintained throughout the 26 weeks of treatment. Sapropterin was well-tolerated with a favorable safety profile. The improvements in ADHD inattentive symptoms and aspects of executive functioning in response to sapropterin therapy noted in a large cohort of individuals with PKU indicate that these symptoms are potentially reversible when blood Phe levels are reduced.

Abstract 5137: Parallel approaches to the discovery of novel BRD4 inhibitors

Epigenetic signalling is essential for the regulation of gene expression and cellular development, and disruption of these pathways has been identified in a wide range of tumours. The ϵ-N-acetylation of lysine residues (Kac) within histone tails is one of the most abundant epigenetic modifications and bromodomain containing proteins (BRD) represent an important class of reader protein that recognize and bind such residues. BRD4 is a critical mediator of transcription, functioning to recruit the positive transcription elongation factor complex (P-TEFb) and resulting in increased expression of growth-promoting genes. Inhibition of BRD4 has been shown to result in tumour growth inhibition both in vitro and in vivo. In addition, BRD4 has been shown to be a proto-oncogene which is mutated by chromosomal translocations in the rare form of NUT midline carcinoma.

Although the interaction between bromodomains and acetylated histone represents a protein-protein interaction, co-crystal structures have demonstrated that Kac is recognized by a central deep hydrophobic cavity, which represents “an attractive druggable pocket”. We performed a virtual screen based on modelling known BRD4 inhibitors in crystal structures of both BRD4 domain 1 and domain 2. The virtual screen used a combination of substructure, shape, electrostatic and docking methods combining the strengths of each of these approaches to select compounds from commercially available sources. In addition, we screened BRD4 binding domain 1 against an Argenta fragment library using surface plasmon resonance. A number of novel hits were identified from these screening approaches (up to 18µM in potency) and crystal structures obtained for key hits.

We developed a comprehensive screening cascade validated with tool compounds for profiling hits, starting with an in vitro Brd4 AlphaScreen binding assay and comprising a number of cellular pharmacodynamic assays evaluating effects on established biomarkers of BRD4 inhibition. These screening assays included mRNA analyses for c-myc, p21 and bcl2, a c-myc promoter reporter assay and were confirmed by Western analyses. Phenotypic assays based on growth inhibition of multiple myeloma and acute myeloid leukemia cell lines were also established.

Citation Format: David H. Jones, Marcel J. de Groot, Robert Heald, Ebenezer Arhin, Ria Goodwin, Brenda Burton, Jan Kulagowski, David Brown, Steven Irving, Richard Bazin, Deborah Bruce, Rene Devos, Steven Price, Nick Ray, Peter Lockey, John Montana, Mark R. Albertella, Simon R. Green. Parallel approaches to the discovery of novel BRD4 inhibitors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5137. doi:10.1158/1538-7445.AM2014-5137

Discovery of novel allosteric mitogen-activated protein kinase kinase (MEK) 1,2 inhibitors possessing bidentate Ser212 interactions

Using structure-based design, two novel series of highly potent biaryl amine mitogen-activated protein kinase kinase (MEK) inhibitors have been discovered. These series contain an H-bond acceptor, in a shifted position compared with previously disclosed compounds, and an adjacent H-bond donor, resulting in a bidentate interaction with the Ser212 residue of MEK1. The most potent compound identified, 1 (G-894), is orally active in in vivo pharmacodynamic and tumor xenograft models.

Chronic relapsing inflammatory optic neuropathy (CRION)

We describe the clinical characteristics and early natural history of a form of inflammatory optic neuropathy which is frequently bilateral and often painful, and is characterized by relapses and remissions. MRI scans of the brain are normal and those of the optic nerves often, but not always, show high signal abnormalities which enhance. The symptoms and signs respond well to corticosteroid treatment, although long-term immuno suppression is often necessary. The syndrome behaves in a way which is typical of the condition known as granulomatous optic neuropathy, but during a median follow-up of 8 (2-26) years in no case has evidence for systemic sarcoidosis been identified. We suggest that the disorder be named chronic relapsing inflammatory optic neuropathy (CRION).

Phenylketonuria in adulthood: a collaborative study

During 1967-1983, the Maternal and Child Health Division of the Public Health Services funded a collaborative study of 211 newborn infants identified on newborn screening as having phenylketonuria (PKU). Subsequently, financial support was provided by the National Institute of Child Health and Human Development (NICHD). The infants were treated with a phenylalanine (Phe)-restricted diet to age 6 years and then randomized either to continue the diet or to discontinue dietary treatment altogether. One hundred and twenty-five of the 211 children were then followed until 10 years of age. In 1998, NICHD scheduled a Consensus Development Conference on Phenylketonuria and initiated a study to follow up the participants from the original Collaborative Study to evaluate their present medical, nutritional, psychological, and socioeconomic status. Fourteen of the original clinics (1967-1983) participated in the Follow-up Study effort. Each clinic director was provided with a list of PKU subjects who had completed the original study (1967-1983), and was asked to evaluate as many as possible using a uniform protocol and data collection forms. In a subset of cases, magnetic resonance imaging and spectroscopy (MRI/MRS) were performed to study brain Phe concentrations. The medical evaluations revealed that the subjects who maintained a phenylalanine-restricted diet reported fewer problems than the diet discontinuers, who had an increased rate of eczema, asthma, mental disorders, headache, hyperactivity and hypoactivity. Psychological data showed that lower intellectual and achievement test scores were associated with dietary discontinuation and with higher childhood and adult blood Phe concentrations. Abnormal MRI results were associated with higher brain Phe concentrations. Early dietary discontinuation for subjects with PKU is associated with poorer outcomes not only in intellectual ability, but also in achievement test scores and increased rates of medical and behavioural problems.

The discovery of RPR 200765A, a p38 MAP kinase inhibitor displaying a good oral anti-arthritic efficacy

RPR132331, a 2-(2-dioxanyl)imidazole, was identified as an inhibitor of tumour necrosis factor (TNF)alpha release from lipopolysaccharide (LPS)-stimulated human monocytes. An intensive programme of work exploring the biology, toxicity and physical chemistry of a novel series of inhibitors, derived from RPR132331, has led to the identification of RPR200765A, a development candidate for the treatment of rheumatoid arthritis (RA). RPR200765A is a potent and selective inhibitor of p38 MAP kinase (IC50 = 50 nM). It inhibits LPS-stimulated TNFalpha release both in vitro, from human monocytes (EC50 = 110 nM), and in vivo in Balb/c mice (ED50 = 6 mg/kg). At oral doses between 10 and 30 mg/kg/day it reduces the incidence and progression in the rat streptococcal cell wall (SCW) arthritis model when administered in either prophylactic or therapeutic dosing regimens. The compound, which is a mesylate salt and exists as a stable monohydrate, shows good oral bioavailabiltiy (F = 50% in the rat) and excellent chemical stability. The data from the SCW disease model suggests that RPR200765A could exhibit a profile of disease modifying activity in rheumatoid arthritis (RA) patients which is not observed with current drug therapies.

Cervical spine injury in child abuse: report of two cases

Pediatric cervical spine injuries have rarely been reported in the setting of child abuse. We report two cases of unsuspected lower cervical spine fracture-dislocation in twin infant girls who had no physical examination findings to suggest cervical spine injury. Classic radiographic findings of child abuse were noted at multiple other sites in the axial and appendicular skeleton. Magnetic resonance (MR) imaging proved to be valuable in both the initial evaluation of the extent of cervical spine injury and in following postoperative changes. The unexpected yet devastating findings in these two cases further substantiate the importance of routine evaluation of the cervical spine in cases of suspected child abuse.

Phaeochromocytoma with central nervous system manifestations

A 35-year-old Samoan male presented with intermittent headaches and hypertensive episodes for several months. A subsequent left adrenal gland phaeochromocytoma was discovered and surgically excised. An MRI of his brain demonstrated periventricular, basal ganglia, and centrum semi-ovale infarction. We suggest that catecholamine excess and neuropeptide Y may contribute to intracerebral haemorrhage and infarcts associated with phaeochromocytomas. Additionally, our surgical approach in removing the phaeochromocytoma is discussed.

Outsourcing inpatient i.v. compounding: expense and medication error implications

A quasi-experiment was conducted to evaluate differences in intravenous (i.v.) drug compounding costs and frequency of medication administration errors of omission before and after outsourcing the hospital's i.v. admixture refill program to an alternate site home i.v. infusion pharmacy. As part of the outsourcing changes, the pharmacy redeployed an i.v. admixture technician to do i.v. recycling on the nursing units. The study was a single subject, pretest, posttest (within subjects) design using an observer. The independent variables were outsourcing and having an i.v. recycling technician. The dependent variables were medication errors of omission and costs directly associated with the two i.v. programs. A statistically significant reduction in the frequency of medication administration errors of omission was associated with implementation of the outsourcing program. In addition, first year expenses were reduced by an estimated $86,356.

Clinical and research applications of real-time ultrasonography in bovine reproduction: a review

Transrectal real-time ultrasonography has proved to be a rapid and reliable technique for studying reproductive functions in cattle. Through ultrasonography it is now established that follicular growth occurs in wave-like patterns during each estrous cycle. It has been shown that follicular growth and regression continue during early pregnancy, as well as in the postpartum anestrous period. Ultrasound has also helped us to understand the influence of dominant follicles on medium and small follicles. Among the numerous demonstrated applications of ultrasonography, early pregnancy diagnosis, fetal sexing, and postpartum reproductive management appear to be promising areas for immediate application. The new information that has been generated through ultrasound has thrown light on hitherto poorly understood areas of ovarian follicular dynamics, corpus luteum function, pregnancy establishment, and embryonic development in cattle, thereby opening newer areas for research. Still there is great potential for the continued application of this technology to further our understanding of the reproductive processes and to maximize reproductive efficiency of the bovine species. The significant contributions of real-time ultrasonography to the study of bovine reproduction in general and its practical applications in particular are discussed in this paper. The need for taking up technology assessment studies and for the introduction of low-cost portable equipment are stressed. Literature search for this review was done by scanning Current Contents Series 1991-92, AGRICOLA 1980-92, and MEDLINE 1990-92.

The development of a simple fecal immunoreactive progestin assay to monitor reproductive function in swine

The objectives of the study were to (a) develop a simple fecal progestin extraction and radioimmunoassay method to measure immunoreactive progestin in porcine feces and (b) to characterize fecal progestin profiles during the estrous cycle and postpartum. A simple extraction method was developed in trial 1 and the mean (+/- SD) progestin recovery of the method was 84.3 +/- 3.5%. Progesterone levels measured at five different spiked concentrations (50, 100, 200, 400, and 500 ng/0.5 g feces) showed no systematic error. The sensitivity of the assay was 0.16 nmol/L of the extract. Trial 2 involved collecting fecal samples from six cycling sows every second or third day, beginning on the day of estrus (day 0) and continuing until day 22. The mean (+/- SD) fecal progestin concentrations of these sows determined by the above assay during days 0-5, days 6-10, days 11-15, and days 16-21 were 87.1 +/- 17.5, 262.6 +/- 102.1, 1188.2 +/- 454.1, and 897.3 +/- 274.1 x 10(-3) nmol/g feces, respectively. In trial 3, fecal samples from six postpartum sows were collected at weekly intervals beginning from day 7 after farrowing until day 50. The mean (+/- SD) fecal progestin concentrations were 111.0 +/- 61.1, 74.1 +/- 21.3, 66.5 +/- 26.1, 122.7 +/- 58.8 and 533.5 +/- 244.2 x 10(-3) nmol/g feces, during days 7-10, days 11-20, days 21-30, days 31-40, and days 41-50 postpartum, respectively. The results indicate that simple fecal progestin extraction and assay are feasible alternatives to the standard blood progesterone assays for monitoring reproductive function in swine.