Treatment of Bardet-Biedl-Syndrome With Metformin for Evaluation of a Possible Visual Improvement (BBS)

Treatment of Infantile and Juvenile Patients With Bardet-Biedl-Syndrome With Metformin. Evaluation of a Visual Improvement as a Side Effect of the Pediatric Treatment of Adipositas - a Prospective Pilot Study Without Control

In this prospective pilot study without control group children and young adults (10-25 years old) diagnosed with Bardet-Biedl syndrome and treated with Metformin for their adipositas will be evaluated for a possible additional effect of Metformin on visual acuity.

Study Overview

• Status: Withdrawn
• Conditions: Visual Impairment; Bardet-Biedl Syndrome
• Intervention / Treatment: Drug: Metformin

Detailed Description

Within experiments with animals a positive effect of Metformin concerning the photo receptors was shown. Several patients of the university hospital Tübingen with Bardet-Biedl-Syndrome and Metformin therapy due to their adipositas reported a subjective improvement of the visual acuity which was confirmed by opthalmologic tests.

This will be checked in a prospective pilot study without control group including children and young adults (10-25 years old) diagnosed with Bardet-Biedl syndrome and treated with Metformin for their adipositas. Therefore a possible additional effect of Metformin on visual acuity will be evaluated under controlled conditions.

• Study Type: Interventional
• Phase: Phase 2

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years to 25 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• clinically confirmed Bardet-Biedl-syndrome
• Visual acuity between 0.05 and 0.8
• Age >=10 year to <25 years
• Visual field III4e or V4e with diameter >=5°, if II4e not seen
• informed consent of patient and/or legal representative

Exclusion Criteria:

• Hypoglycaemia (<50mg/dl)
• Therapy with Metformin within the last three months
• Participation in another clinical trial
• pregnancy, lactation
• any contra indication concerning Metformin therapy
• Renal failure (creatinine clearance < 60ml/min)
• any acute disorder accompanied by clouding of consciousness
• acute or chronic disorders possible accompanied by tissue hypoxia
• Liver insufficiency, alcohol abuse
• not fluent in German language

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Metformin Therapy; Metformin therapy once daily for 24 weeks with a dose of 500, 850 or 1000 mg depending on body weight	Drug: Metformin; 500, 850 or 1000 mg depending on body weight once daily for 24 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual acuity	Course of visual acuity according to appropriate table	Baseline to day 210

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of letters read	Course visual acuity defined as number of letters read	Baseline to day 210
Results of Static perimetry	Course of results of static perimetry given by measurement of light contrast sensitivity within at least 5 central points.	Baseline to day 210
Results of Kinetic perimetry	Course of results of kinetic perimetry given by mapping the visual field sensitivity boundaries using Goldmann perimetry	Baseline to day 210
Electroretinogram (ERG) dim-flash	Course of values of ERG dim-flash	Baseline to day 210
Electroretinogram (ERG) standard flash	Course of values of ERG standard flash at 3 ods/m2	Baseline to day 210
Electroretinogram (ERG) cone-single-flash	Course of values of ERG cone-single-flash at 30cd/m2	Baseline to day 210
Electroretinogram (ERG) 30-Hz-Flicker	Course of values of ERG measured by 30-Hz-Flicker in all patients	Baseline to day 210
Visual evoked potential (VEP) - amplitude	Course of results of measurement of VEP amplitude	Baseline to day 210
Visual evoked potential (VEP) - latency time	Course of results of measurement of VEP latency time	Baseline to day 210
FST	Full-Field-Stimulus Threshold	Baseline to day 210
optical coherence tomography (OCT)	Course of central thickness of retina measured by OCT	Baseline to day 210

Collaborators and Investigators

• Sponsor: University Hospital Tuebingen
• Investigators: Principal Investigator: Heiko Billing, PD Dr. med., Universtitätsklinikum Tübingen

Study record dates

Study Major Dates

• Study Start (Anticipated): April 1, 2018
• Primary Completion (Anticipated): October 1, 2019
• Study Completion (Anticipated): August 1, 2020

Study Registration Dates

• First Submitted: March 19, 2018
• First Submitted That Met QC Criteria: March 29, 2018
• First Posted (Actual): April 6, 2018

Study Record Updates

• Last Update Posted (Actual): April 18, 2019
• Last Update Submitted That Met QC Criteria: April 16, 2019
• Last Verified: February 1, 2018

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Eye Diseases; Neurologic Manifestations; Disease; Congenital Abnormalities; Genetic Diseases, Inborn; Hypothalamic Diseases; Eye Diseases, Hereditary; Sensation Disorders; Abnormalities, Multiple; Ciliopathies; Retinitis Pigmentosa; Syndrome; Vision, Low; Vision Disorders; Bardet-Biedl Syndrome; Laurence-Moon Syndrome; Hypoglycemic Agents; Physiological Effects of Drugs; Metformin
• Other Study ID Numbers: BBS V1.0

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No