NCT04578652

Fiber Supplementation and Metformin Combination Therapy in Adolescents With Severe Obesity and Insulin Resistance: Interactions With the Gut Microbiome.

Recruiting now Phase 3 Last updated 14 November 2025

What this trial tests

Phase 3 trial testing Metformin 850 mg oral tablet bid in Obesity, Childhood in 90 participants. Currently enrolling.

Timeline

22 October 2021

Primary endpoint
1 September 2026

1 September 2026

Quick facts

Lead sponsor	University of Alberta
Phase	Phase 3
Status	Recruiting now
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	double
Primary purpose	treatment
Enrollment	90
Start date	22 October 2021
Primary completion	1 September 2026
Estimated completion	1 September 2026
Sites	1 location across Canada

Drugs / interventions tested

• Metformin 850 mg oral tablet bid — full drug profile →
• Supplemental fiber mixture (35 g total) composed of 6g of Oligofructose + 12g of resistant maltodextrin + 12g of acacia gum + 5g of PGX.

Conditions studied

• Obesity, Childhood — all drugs for Obesity, Childhood →
• Insulin Resistance — all drugs for Insulin Resistance →

Sponsor

University of Alberta

Who can join

Adults 12 to 18, any sex, with Obesity, Childhood or Insulin Resistance. Patients with the condition only — healthy volunteers not accepted.

What's being measured

Primary outcomes are the specific endpoints the trial is designed to prove or disprove.

• Changes in HOMA-IR
  Time frame: Baseline, 6, and 12 months
  Change in HOMA-IR value

Sponsor's own description

This is a 12-month, single center, three-arm parallel design, double-blind, randomized clinical trial, to compare the effects of supplemental dietary fiber and metformin (MET) alone and in combination over 12 months on glucose metabolism (insulin resistance \[IR\]), inflammation and BMI in adolescents with obesity and IR, and to assess the relationship between therapeutic intervention(s) and changes in gut microbiome composition and function.

Since MET and FIBER have been shown to reduce weight and increase insulin sensitivity through distinct but overlapping mechanisms of action, our central hypothesis is that the combination of FIBER + MET will have a synergistic effect and be more effective than FIBER or MET alone in improving metabolic function (IR) and reducing BMI and inflammation in adolescents with obesity, IR and family history (FM) of T2DM.

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Publications & conference data

2 peer-reviewed publications reference this trial (live from Europe PMC):

1. Efficacy of metformin and fermentable fiber combination therapy in adolescents with severe obesity and insulin resistance: study protocol for a double-blind randomized controlled trial.
   Deehan EC, Colin-Ramirez E, Triador L, Madsen KL, et al · · 2021 · cited 2× · PMID 33596993 · DOI 10.1186/s13063-021-05060-8
2. Extinguishing the Fire: Treating Pediatric Type 2 Diabetes by Targeting Obesity Treatment.
   Bensignor MO, Hsia DS, Van Name MA, Jastreboff AM, et al · · 2025 · PMID 40730197 · DOI 10.2337/dci25-0031