Active clinical trials for "Fructose Intolerance"

Hereditary fructose intolerance (HFI) is a rare inborn error of metabolism. Patients with HFI develop acute abdominal pain, nausea, vomiting, hypoglycemia and proximal tubular dysfunction upon consumption of a fructose containing food product. In rare cases, (prolonged) fructose consumption can even lead to liver and kidney failure. Patients with HFI are therefore treated with a lifelong fructose-restricted diet. Animal studies have shown that the clinical manifestations of HFI are abrogated upon inhibition of ketohexokinase (KHK), the enzyme that catalyses the first step in fructose metabolism. Recently, PF-06835919, a KHK inhibitor (KHKi), was developed as a new treatment for non-alcoholic fatty liver disease. The compound was well tolerated in several phase II clinical trials. It is hypothesized that PF-06835919 is also effective in patients with HFI.

Background: Over the past few decades, fructose is increasingly being used as a sweetener/ additive in a variety of foods. Incomplete absorption of fructose has been implicated as a cause of gastrointestinal symptoms. In tertiary care centers, the prevalence of fructose malabsorption in subjects with unexplained GI symptoms is thought to be between 11-50%, when assessed with breath tests following administration of 25 grams of fructose in a 10% solution. Restriction of dietary fructose has been shown to improve symptoms in these patients to an extent. Currently, there are no therapeutic agents that improve intestinal fructose absorption and thereby decrease symptoms. Studies in the pediatric population have shown that fructose absorption in the small intestine is increased in the presence of glucose or amino acids, especially alanine. Objective: The investigators' objective is to assess whether co-administration of an oral solution of L-alanine facilitates fructose absorption and decreases gastrointestinal (GI) symptoms associated with fructose malabsorption in subjects undergoing standard fructose breath test when compared to placebo. Methods and analysis: The investigators propose a randomized, double-blind study in 40 subjects with known fructose intolerance. After an overnight fast, each subject will receive an oral solution of 12.5 grams of alanine in 125cc of water or placebo. Next, the subject will receive an oral solution of 25 grams of fructose in a 10% solution. Serum, urine and breath samples will be collected at baseline and at 30-minute intervals for 4 hours. GI symptoms will also be assessed and recorded at 30 minute intervals using a standard questionnaire. Repeated measures ANOVA will be used to compare the data obtained during the study protocol with the baseline (pre-study) data. Expected outcomes: Co-administration of alanine with fructose may improve fructose absorption and decrease symptoms in subjects with fructose intolerance. Hypothesis: Ingestion of alanine along with fructose, will facilitate intestinal absorption of fructose in subjects with fructose malabsorption. Aim: To investigate the effects of co-administration of equi-molar doses of alanine on a) the absorption of fructose and b) the occurrence of GI symptoms in subjects with fructose malabsorption.

Data suggest that alanine may facilitate the intestinal absorption of fructose in patients with DFI and thereby may decrease GI symptoms. We hypothesize that the ingestion of supplemental L-alanine along with mixed meals or snacks that contain foods with free fructose or high fructose content will decrease GI symptoms in subjects with dietary fructose intolerance by facilitating intestinal absorption of fructose. Aim: To investigate the effects of co- administration of equi-molar doses of L-alanine or placebo on the occurrence of GI symptoms in subjects with dietary fructose intolerance, in a randomized, double blind, cross over study. Methods: We propose to investigate the effects of co-administration of equi-molar doses of L-alanine or placebo on the occurrence of GI symptoms in 70 subjects with dietary fructose intolerance, in a randomized, double blind, cross over study. Data Analysis: The primary outcome measure will be a comparison of baseline breath sample values and study visit breath sample values. Additionally, we will assess subject-reported occurence and severity of nine gastrointestinal symptoms during the test on a visual analog scale (VAS). Expected Results: We anticipate that dietary fructose intolerance (DFI) symptoms will improve with ingestion of supplemental L-alanine (along with foods containing free fructose or high fructose content). We additionally expect treatment of DFI with administration of L-alanine powder to be more practical than co-ingestion of alanine-rich foods, and more convenient for patients.

Different published studies has shown a possible co-variation between leakage of fructose to the great bowel and exacerbation of irritable bowel syndrome (IBS) symptoms. The aim of the FINN trial is to study the role of fructose malabsorption in patients with IBS in order to evaluate different diagnostic criteria for fructose malabsorption and at the same time study the effect of diet treatment in this cohort of patients and estimate the prevalence of fructose malabsorption.

Fructosin® is a medical device for use in fructose intolerance. In this uncontrolled posdt market clinical follow up (PMCF) study, the safety and efficacy of oral supplementation of Fructosin® in fructose intolerance will be investigated. The study participants will be informed about the nature and scope of the study during a preliminary examination (screening) and a declaration of consent will be obtained. In addition, it is determined whether fructose intolerance is present. This is determined by means of the aCPQ test. Subsequently, the patients fill out symptom questionnaires (IBS-SSS, IBS-QoL, 1-week symptom questionnaire). After the eligibility check, a 14-day phase of monitoring and documentation of symptoms and complaints without taking Fructosin® (observation phase) takes place. At visit 1, the patients receive the Fructosin® capsules, which they take as needed, but no more than 2 x 3 times a day with fruit meals. The intake phase runs over a period of 28 days (4 weeks) during which the study participants observe and evaluate gastrointestinal symptoms with the help of the 1-weekly symptom questionnaire. In addition, the daily fructose consumption (fruit, fruit juices, smoothies) and the amount of Fructosin® capsules taken are documented in a diary.

The purpose of this study is to determine whether the enzymatic product Frucosin(R) is able to degrade fructose in vivo in the small intestine of patients with known fructose malabsorption by measuring hydrogen in the expiratory air.

This study aimed to examine metabolic response to a short-term fructose enriched diet in carriers for hereditary fructose intolerance compared to controls. Effects of fructose coffees will be assessed in 7 healthy volunteers and 7 subjects with heterozygous mutation for ALDOB gene in a randomized, controlled, crossover trial.

Background: High fructose intake increases blood lactate, triglyceride and uric acid concentrations. Uric acid may contribute to insulin resistance and dyslipidemia in the general population. In patients with hereditary fructose intolerance fructose consumption is associated with acute hypoglycemia, renal tubular acidosis, and hyperuricemia. Objective: We investigated whether asymptomatic carriers for hereditary fructose intolerance (HFI) would have a higher sensitivity to adverse effects of fructose than the general population. Design: Eight subjects heterozygous for HFI (hHFI; 4 males, 4 females) and eight controls received for 7 days a low fructose diet and on the eighth day ingested a test meal calculated to provide 25% of basal energy requirement containing labeled fructose (13C fructose 0.35 g/kg), protein (0.21 g/kg) and lipid (0.22 g/kg). Total fructose oxidation, total endogenous glucose production (by 6,6-2H2-glucose dilution), carbohydrate and lipid oxidation, lipids, uric acid, lactate, creatinine, urea and amino acids were monitored for 6 hours.

Over the past few decades, fructose consumption has risen significantly in the United States1. This sugar is increasingly being used as a sweetener in a variety of foods1. Because there is a limited absorptive capacity for fructose, excessive ingestion of fructose leads to fructose malabsorption and dietary fructose intolerance (DFI) 2-9, 13. Incomplete absorption of fructose may lead to a variety of gastrointestinal symptoms, including bloating, pain, gas and diarrhea 2-9. In tertiary care centers, the prevalence of DFI in subjects with unexplained GI symptoms has been estimated to range between 11-50 %, when subjects were assessed with breath tests following administration of 25 grams of fructose 2, 5-7. Currently, the main treatment for DFI consists of restricting the intake of fructose-containing foods 10-12 or limiting the intake of foods with excess "free fructose" (ie, fructose in excess of glucose) or a high fructan content17. These diet restrictions can improve symptoms in patients with DFI 10-12,17. However, the diet is very restrictive and imposes a significant burden on the individual and the family. In one study, 40% of subjects were unable to comply with dietary restrictions 10. Currently, there are no other therapeutic agents for treating this condition 14, 15. Apart from promoting intestinal fructose absorption, an ideal therapeutic agent should be safe, simple to use, inexpensive and have no calorific value. Fructose is mostly absorbed in the small intestine by facilitated diffusion which is mediated by the GLUT-5 transporter protein. This protein is expressed on the intestinal mucosal surface. In the presence of glucose, fructose absorption is increased, mostly due to co-transport with glucose via the GLUT-2 transporter protein. However, the calorie content of glucose precludes its routine use in patients with DFI. Other compounds that promote fructose absorption, such as 3 O-methyl glucose and epidermal growth factor (EGF) have significant side effects and safety issues, making them unsuitable for clinical use in DFI. Several amino acids, including alanine, have been also been shown to increase intestinal fructose absorption 14. The postulated mechanism is as follows: transmucosal Na+-coupled amino acid transport causes increased water flow through the mucosal apical membrane14. This, in turn, facilitates fructose absorption by a process of 'solvent drag', caused by an increase in intraluminal fructose concentration caused by water removal from the lumen14. The potential benefit of alanine was assessed in a European study in healthy children 14. Ten subjects underwent H2 breath tests following administration of fructose alone (2g/ Kg body weight), followed by a combination of fructose and an equi-molar dose of various amino acids (L-alanine, L-phenylalanine, L-glutamine, L-proline) or glucose. Breath H2 production was assessed as a marker of intestinal fructose absorption. Subjects were asked to report any gastrointestinal symptoms during the test. All subjects had a positive (>20 ppm of H2) breath test (68 ± 38 ppm) with fructose and 6/10 subjects reported either abdominal pain or diarrhea during the test. Co-administration of alanine caused a significant (p < 0.05) decrease in breath H2 production (3 ± 3 ppm), suggesting increased intestinal fructose absorption. Furthermore, none of the subjects reported any gastrointestinal symptoms during the test.

In this study we will investigate the expression of the fructose transport protein GLUT5 in the small intestine in patients with functional GI disoders and fructose intolerance compared to matched healthy controls.