View clinical trials related to Urea Cycle Disorders.
Filter by:Urea cycle disorders (UCDs) are dramatic congenital inherited metabolic disorders. There is no cure. Many novel therapeutic approaches are currently being developed, which hopefully will change the current situation. Testing the efficacy of such new therapies in patients is a challenge, because many clinical parameters are influenced by several disturbances and biochemical parameters are often not very specific. The measurement of ureagenesis is a tool to analyze the entire function of the urea cycle in a single test. This is more meaningful for the characterization of UCD patients than the analysis of single metabolites or enzymes. Therefore, the test will be important to evaluate current and future novel therapies. The term "ureagenesis" means "production of urea", which is the main task of the urea cycle. This total urea production can be measured with a "tracer" (in this case a stable ammonium chloride isotope). This tracer is non-radioactive and non-toxic. It is for example used as an unmarked substance in cough syrup, diuretic drugs and as food additive. Thus, the tracer does not pose a risk to the participant, especially since only a very low dose is applied. The investigators will analyze specific substances from the urea cycle (namely [15N, 14N] urea and several [15N] amino acids) that are produced during the test and compare them with results from healthy people. The maximum test duration is 5 hours. This project is being carried out at one site, namely the University Children's Hospital in Zurich. This project is being carried out under Swiss law. The responsible Ethics Committee has reviewed and approved the study.
This clinical food study aims to explore the effect of KB195, a novel mixture of oligosaccharides, on the metabolism of nitrogen by the microbiome in patients with urea cycle disorders (UCDs). This will be done using a stable isotope to assess nitrogen metabolism in the blood, urine, and stool. The study will also assess the safety and tolerability of KB195 in patients with UCDs.
In proximal urea cycle disorders (UCD), particularly ornithine transcarbamylase deficiency (OTCD), hyperammonemia (HA) causes increased brain glutamine (Gln) which perturbation is thought to be at the core of the neurological injury. In contrast, in distal UCD such as citrullinemia (argininosuccinate synthetase deficiency; (ASSD) and argininosuccinic aciduria (argininosuccinate lyase deficiency); (ASLD) cognitive impairment and neuropsychiatric disease are common even in the absence of acute HA. As a consequence, both citrulline and argininosuccinate (ASA) or their metabolic products have been implicated as neurotoxic. In this project the investigators will use state-of- the-art neuroimaging and neuropsychological methods to investigate whether patients with OTCD have chronically elevated brain Gln and reduced myo-inositol (mI) levels that correlate with regional brain structural abnormalities and neurocognitive dysfunction. The researchers will further investigate whether during an acute episode of HA elevated brain Gln and decreased mI levels correlate with the magnitude of cytotoxic edema and whether a Gln/mI ratio threshold can be identified at which the cytotoxic edema is followed by cell loss. Finally, the researchers will investigate whether regions of brain damage in ASSD and/or ASLD are distinct from those in OTCD and compare brain Gln levels in ASSD and ASLD in the absence of HA to those in OTCD. The investigators will also seek to determine if brain citrulline and ASA can be identified in the brains of patients with distal UCD and whether they correlate with brain abnormalities seen in MRI and neuropsychological testing. This project will elucidate the chronology of brain pathology both in acute hyperammonemia and chronic UCD and whether, proximal and distal UCD differ in their pathophysiology of brain damage.
Urea cycle disorders (UCD) are genetic disorders caused by the liver's inability to break down ammonia from proteins; ammonia then accumulates and is toxic to the brain. UCD cause brain damage and intellectual and developmental disabilities and even death. Treatment for UCD is either conservative management which involves a low-in-protein diet, drugs, and amino acid supplements or liver transplantation; each carries their own risks. This study aims to help patients to make the decision about different management alternatives by providing them with scientific information that is currently lacking. Aim 1 of this study will compare survival, neurocognitive function, and patient-reported quality of life.
The aim of the study is to assess the efficacy of HepaStem treatment in paediatric patients suffering from urea cycle disorders.
The purpose of this study is to determine if patients participating in "The Longitudinal Study of Urea Cycle Disorders" are different than participants in the Urea Cycles Disorders Consortium (UCDC) Rare Diseases Clinical Research Network (RDCRN) Contact Registry and to determine if patients are a good source of medical information.
This is a study involving a dietary supplement. Patients with argininosuccinic aciduria will be randomly assigned to receive either a nitric oxide dietary supplement or placebo for 2 weeks, and then crossed-over to receive the other treatment for two weeks. The investigators expect to see that : 1) Patients with ASA will have a decreased ability for their arteries to dilate due to nitric oxide deficiency, 2) Treatment of ASA with the nitric oxide supplement will improve the ability of their arteries to dilate, and 3) Through the testing of subjects' fibroblasts (cells in connective tissue that produce collagen and other fibers), the investigators hope to predict which patients may respond NO supplementation.
The purpose of this study is to assess the long-term safety follow-up of patients having been treated with HepaStem.
The purpose of this study is to assess the safety and to appraise the efficacy of one cycle of Hepastem (Heterologous Human Adult Liver-derived Progenitor Cells, HHALPC) infusions in paediatric patients suffering from CN or UCD. The study duration: 12 months starting from the day of treatment: 6 months active surveillance and 6 months observation post-infusion.
This is a pilot study which will test the safety and feasibility of hypothermia treatment as adjunct therapy to conventional treatment of hyperammonemic encephalopathy (HAE) in neonates versus conventional treatment (dialysis, nutritional therapy, and ammonia scavenging drugs) only. The endpoint of the pilot study will be reached when either 24 patients have been enrolled and no serious adverse events were observed, when no patient has been enrolled in 5 years, or when serious adverse events occur which are clearly linked to the use of hypothermia. These would be serious complications not seen in patients on conventional therapy (dialysis , nutritional therapy, ammonia scavenging drugs) for HAE.