Skip to content

Effect of Oral 6-bromotryptophan on Safety, Pharmacokinetics and Efficacy in Metabolic Syndrome Individuals

Effect of 4 Weeks of Oral 6-bromotryptophan on Safety, Pharmacokinetics and Efficacy in Metabolic Syndrome Individuals (2022)

Status
UNKNOWN
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05971524
Acronym
BROMO
Enrollment
36
Registered
2023-08-02
Start date
2023-05-04
Completion date
2025-02-01
Last updated
2023-08-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diabetes Mellitus, Metabolic Syndrome

Brief summary

Safety, pharmacokinetics and efficacy of a novel endogenous plasma metabolite, 6-bromotryptophan, will be established in metabolic syndrome/ insulin resistant participants.

Detailed description

Rationale: A newly identified endogenous plasma microbiome-derived tryptophan metabolite, 6-bromotryptophan (6-BT), was associated with preserved beta-cell function and diminished circulating T cell count in (T1D) type 1 diabetes patients. Anti-inflammatory and insulin-secratogogue effects were established in in vitro- and murine studies in both the setting of type 1 and type 2 diabetes. Also, 6-BT did not show any toxic effects in cells or in vivo experiments. In order to obtain safety data before the investigators progress to an efficacy study in T1D, the investigators aim to perform a phase I/II trial of 6-BT in metabolic syndrome individuals. If safe, 6-BT may hold a promise as a food supplement in type 1 and 2 diabetes. Objective: To assess safety, pharmacokinetics and efficacy of oral dosage of 6-BT in individuals with metabolic syndrome Study design: A phase I/II, dose finding, placebo controlled, double blinded trial. Study population: Metabolic syndrome individuals or participants with insulin resistance, age 35-70 years, without use of medication. Intervention (if applicable): Participants will be given placebo, 2mg, 4mg or 8mg of 6-BT capsules once daily for 4 weeks (n=9 per arm, total of 36 participants). Main study parameters/endpoints: The principal outcome will be patient safety and tolerability (biochemical parameters of kidney and liver function and complete blood count, adverse events) in relation to improvements in glucose homeostasis (mixed-meal tests and continuous glucose monitoring). Secondary read-outs will include changes in: immunological profile (ex vivo stimulation of monocytes, and immunophenotyping of peripheral blood mononuclear cells (PBMC)) and gut microbiome composition (16s ribosomal ribonucleic acid (rRNA) sequencing). Also, liver fat content will be determined before and at end of the trial by MRI. As this food derived metabolite is given to humans for the first time, the investigators will also study its pharmacokinetics by measuring serum 6-BT concentrations in serum and urine at different time-points after oral intake. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: 6-BT is an endogenous (food tryptophan derived) metabolite found in the human circulation. Our previous trail has shown that fecal microbiota transplantations (FMT) can modulate and increase plasma 6-BT levels with a positive association with C-peptide (as marker of pancreatic beta cells function). Additionally, recent investigations have linked higher plasma 6-BT levels with lower risk of kidney disease progression, supporting the health benefits of 6-BT beyond T1D. Hence, the investigators do not foresee major adverse reactions. As there is an urgent need for halting diabetes progression, patients would benefit from the development of new endogenously occurring therapeutic agents.

Interventions

DIETARY_SUPPLEMENT6-BT

2,4 or 8mg of 6-BT once daily for 4 weeks

DIETARY_SUPPLEMENTPlacebo

A placebo capsule once daily for 4 weeks

Sponsors

Nordin Hanssen
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Masking description

To maintain the blinding of the subject and investigators, the identifying labels will be removed from the intervention product at the AMC pharmacy. The study product will be labelled with subject specific information prior to delivery to the study physician, who will hand over the intervention to the participant.

Intervention model description

A phase I/II, dose finding, placebo controlled, double blinded trial

Eligibility

Sex/Gender
MALE
Age
35 Years to 70 Years
Healthy volunteers
No

Inclusion criteria

• Metabolic syndrome, defined as: \- ≥3 criteria out of the 5 following criteria: * fasting plasma glucose ≥5.6 mmol/L * triglycerides ≥1.7 mmol/L * waist circumference ≥102 cm * high-density lipoprotein cholesterol ≤1.04 mmol/ * blood pressure ≥130/85 mm Hg. AND/ OR Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (\>2.5) * Male * Caucasian * 35-70 years old

Exclusion criteria

* Use of systemic medication (except for paracetamol), including proton pump inhibitors, antibiotics and pro-/prebiotics in the past three months or during the study period. * A history of a cardiovascular event * A history of cholecystectomy * Overt untreated gastrointestinal disease or abnormal bowel habits * Liver enzymes\>2.5 fold higher than the upper limit of normal range * Smoking * Exclusion criterion for MRI liver (see E4\_BROMO\_vragenlijst MRI) * Alcohol abuse

Design outcomes

Primary

MeasureTime frameDescription
Glycemic control4 weeksChanges in fasting glucose (mmol/L)
Changes in trombocytes4 weeksNumber of patients with trombocytes \<150 x 10E9 cells/L
Changes in aspartate aminotransferase (AST)4 weeksNumber of patients with AST \> 43 IU/L
Changes in alanine aminotransferas (ALT)4 weeksNumber of patients with ALT \> 45 IU/L
Changes in alkaline phosphatase (ALP)4 weeksNumber of patients with ALP \> 126 IU/L
Changes in Gamma-glutamyltransferase (GGT)4 weeksNumber of patients with GGT \> 117 IU/L
Changes in total bilirubin4 weeksNumber of patients with total bilirubin \> 24 micromol/L
Mixed meal test4 weeksChanges in area under the curve (AUC) of glucose after mixed-meal test
Time-in-range4 weeksIncrease in Time-in-range (TIR,%), a parameter of continuous glucose monitoring devices, where TIR can be between 0 and 100%. A higher TIR reflects a better outcome.
Continuous glucose monitoring4 weeksDecrease in glucose variability (GV, %), a parameter of continuous glucose monitoring devices, where GV can be between 0 and 100%. A lower GV reflects a better outcome.
Adverse events4 weeksNumber of adverse events
renal function4 weeksNumber of participants with a decreased kidney function, defined as a rise in serum creatinine of \>26,5 micromol/L in 48 h
Questionnaires4 weeksChanges in Gastro-intestinal Quality of Life Index (GIQLI score) (points). The minimum and maximum score are 31 and 155 points respectively, and a higher score reflects a better outcome.
Occurence of anemia4 weeksNumber of patients with Hb \< 8,5 mmol/L
Changes in leucocytes4 weeksNumber of patients with leucocytes \<4,0 or \>10,5 x10E9 cells/L

Secondary

MeasureTime frameDescription
Immunologic profile6 weeksAbsolute counts of different immunologic cell types using Cytometry by time of flight (CyTOF) mass cytometry at baseline, 4 weeks and 6 weeks.
6-BT pharmacokinetics6-BT pharmacokinetics as described above will be performed at baseline and after 4 weeks.Quantitatively measuring plasma concentrations of 6-BT at -15, 30, 60, 90, 120, 240 and 300 minutes following 6-BT capsule ingestion
Hepatic stiffness0 and 4 weeksHepatic stiffness will be determined non-invasively by MRI using a special hepatic scanning protocol of 30 minutes
Hepatic fat content0 and 4 weeksHepatic fat content will be determined non-invasively by MRI using a special hepatic scanning protocol of 30 minutes
Dietary intake4 weeksParticipants are asked to fill out an online dietary questionnaire for the 3 days prior to study visit 2,3,4,5 and 7
Low-density lipoprotein (LDL)4 weeksChanges in LDL (mmol/L)
High-density lipoprotein (HDL)4 weeksChanges in HDL (mmol/L)
Triglycerides4 weeksChanges in triglycerides (mmol/L)
Intestinal microbiota composition4 weeksChanges from baseline of relative abundance (%) of bacterial phyla, genera and species between groups and within participants.

Countries

Netherlands

Contacts

Primary ContactNordin MJ Hanssen, dr.
n.m.j.hanssen@amsterdamumc.nl020-56691111

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026