Active clinical trials for "Phenylketonurias"

The PICO-Study is a randomized, placebo-controlled, crossover, non-inferiority trial conducted to add evidence to the current European treatment guidelines for adult patients with phenylketonuria.

The study has shown that the strengthening program applied to the families of children diagnosed with phenylketonuria (PKU) and the education given; It will be conducted in order to examine the effect of the family's coping attitudes, knowledge scores about the disease and its management. The research is of the randomized controlled experimental type. Children from PKU constitute the universe in the city center of Van. The families of children between the ages of 0-3 who were diagnosed with PKU will form the sample of the study. A nursing strengthening program will be applied to families in the experimental group for 10 weeks. The scope of this program; It consists of face-to-face training on disease management, giving the educational guide (booklet) for the families of babies diagnosed with PKU, telephone calls during the education process and counseling services. No application will be made to the families in the control group. After the application of the last tests to the control group; Face-to-face training and a booklet will be given to the experimental group. Data; It will be collected with 'Child and Family Introductory Information Form', 'Parents' Information Level Assessment Form about Phenylketonuria' and 'Coping Attitudes Assessment Scale'. In the literature, there is no study showing the effect of the education given to the families of babies diagnosed with PKU on their coping attitudes. Based on the need to fill this knowledge gap in the literature, it is thought that the study will contribute to the field of child health and disease nursing.

20 participants with PKU will build-up their dietary intake of PKU sphere over 2-16 weeks, depending on their level of metabolic control whilst doing so. Participants will complete a gastrointestinal specific and PKU specific questionnaire at the Baseline clinic visit and record the amount of PKU sphere taken each day. Dried blood spots are taken twice per week. Once built up to a clinically appropriate intake of PKU sphere, or after 16 weeks, participants enter a 4-week Evaluation Period. The amount of PKU sphere taken per day continues to be recorded by participants. Gastrointestinal tolerance over the preceding seven days is recorded at the end of each week. Evaluations of PKU sphere's palatability are made at the end of weeks two and four of the Evaluation Period. Dried blood spots are taken once per week. The participant attends an End of Study Visit at the clinic and the investigator decides whether they should continue taking PKU sphere.

This study centres around a new one-a-day phenylalanine-free protein substitute for phenylketonuria patients. Fifty eligible adults (≥ 16 years) with proven phenylketonuria or hyperphenylalaninemia will be recruited and randomly allocated to one of two intervention arms (n = 25 per arm). Following a 3-day baseline period, and in addition to routine nutritional management, patients will receive either one sachet of the new protein substitute daily (intervention) or continue their usual dietary and/or protein substitute regimen (maximum of 1 protein substitute per day (equal to 20g protein equivalent) control) for 28 days.

This study will evaluate the safety, gastrointestinal (GI) tolerance, acceptability and compliance of a Glycomacropeptide-based protein substitute for patients with Phenylketonuria (PKU).

Low-phenylalanine diets are commonly prescribed to people with phenylketonuria (PKU), an inborn disease which causes accumulation of amino acid phenylalanine (Phe) in the blood. High blood Phe levels can cause mental, behavioural, neurological, and physical problems. Thus, low-phenylalanine diets help patients to manage their condition but it is not clear whether they have an impact on appetite, energy intake and changes in body weight. This is important to explore as prevalence of obesity in this population is rising high. This study aims to find out the effect of PKU-type meals on appetite, appetite biomarkers, and post-meal energy expenditure. The investigators will recruit 26 healthy adults and ask them to participate in two experimental trials. On one occasion the participants will be asked to consume a PKU-supplemented drink followed by a PKU type-lunch and on another occasion the supplement and lunch will be based on normally consumed foods. Series of blood samples will be taken and appetite will be assessed during both experiments. Both experimental trials will finish with consuming an "all-you-can-eat" buffet.

Most forms of Phenylketonuria and hyperphenylalanemia are caused by mutations in the PAH gene (phenylalanine hydroxylase) which is responsible for the conversion of Phe into tyrosine, in the presence of the molecular oxygen and cofactor tetrahydrobiopterin (BH4). To prevent mental retardation due to the buildup of neurotoxic metabolites of Phe, patients with severe PKU must be treated with a low-Phe diet starting early in their life [1]. Although Phe-restricted diet control is essential for avoiding neurological impairment, the life-long compliance with this dietary control is not optimally maintained, particularly in adulthood and adolescence [2]. Non-adherence to dietary control after successful treatment in early childhood may contribute to lower intelligence quotient (IQ), emotional and behavioral disorders, including attention deficit disorders, depression, anxiety, and agoraphobia. In recent years, another therapeutic approach for managing PKU is to supplement a synthetic form of BH4 along with diet control. Kure et al. and several other research teams had indicated that treatment with BH4 might lower down the Phe level in a subset of PKU patients [3-7]. BH4 acts as a pharmacological chaperone to stabilize mutant enzymes with disrupted tetramer assembly and increased sensitivity to proteolytic cleavage and aggregation. The BH4-supplementation therapy (Kuvan) can be used to loosen or even replace burdensome dietary treatment of PKU patients. Correct and efficient identification of BH4-responsive patients is important, both to improve the fast assessment, as well as to avoid false expectations and unnecessary costs. Unfortunately, there is still no golden standard on how to assess BH4 responsiveness most efficiently. In Taiwan, high-dose BH4 [20mg/kg] loading is the standard test to identify patients who are responsible to BH4 treatment, for PAH deficiency PKU patients with more than 30% decrease in Phe level within 24 hours after BH4 challenge were BH4-responsive patients and eligible for national health insurance coverage of continuous BH4 treatment. In clinical studies, blood Phe levels in patients who are BH4-responsive typically decrease within 24 hours after a single administration of Kuvan, although the maximal effect on blood Phe levels may take up to a month. A Phase IV open-label trial showed that of 64% of patients responded to Kuvan within 7 days whereas 10% responded between 8-28 days. To the best of our knowledge, there's no previous study which evaluated longer than 7 days BH4 response test in Asian countries, and for the purpose to help PAH deficiency PKU patients achieve optimal Phe control and neurocognitive outcomes, it's definitely worthy to extend the period of BH4 response test to identity more patients who can benefit from Kuvan treatment.

The purpose of this study is to determine whether improvements in behavior occur in children with phenylketonuria (PKU) who are taking Kuvan.

The investigators will use different types of brain imaging (MRI) in patients with Phenylketonuria (PKU) who are currently not on a strict diet to test the hypothesis that there is improvement in brain circuitry and biochemistry after return to diet and/or sapropterin dihydrochloride (Kuvan).

The purpose of this study is to see how tetrahydrobiopterin therapy (BH4; also known as sapropterin dihydrochloride or Kuvan) affects measures of oxidative stress and endothelial function in patients with Phenylketonuria (PKU).