The Role of Antioxidant Supplementation in Keratoconus Patients

August 11, 2021 updated by: Ellen Koo, University of Miami

The Role of Antioxidants in Keratoconus Patients-A Randomized Controlled Trial of Oral Supplementation of Glutathione, Vitamin A, Vitamin C and Vitamin E

Keratoconus is the most common primary cornea ectasia, where the cornea undergoes structural changes, leading to loss of tissue integrity and vision loss. The prevalence of Keratoconus is 1:2000 in the general population. Oxidative stress has been thought to have a major effect in the disease pathogenesis of Keratoconus. In vitro studies have shown increase in metabolites related to oxidative stress in Keratoconus disease, and that Keratoconus cells undergo increased oxidative stress and tissue damage. Animal models have shown a therapeutic effect of Vitamin C (ascorbate) in corneal wound healing. Glutathione and Vitamins A, C, and E are important antioxidants in the human body. To this date, the role of systemic antioxidant supplementation in Keratoconus patients has yet to be studied. In addition, it has yet to be established as to whether there is a correlation between serum antioxidant levels, and the severity of disease in the Keratoconus patient. The investigators propose to investigate the plasma levels of antioxidants in relation to disease severity. The investigators will also investigate the role of antioxidant supplementation-consisting of parenteral Glutathione (GSH), and Vitamins A, C and E-in delaying the disease progression in Keratoconus.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Withdrawn

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Florida
      • Palm Beach Gardens, Florida, United States, 33418
        • Bascom Palmer Eye Institute-- Palm Beach Gardens

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

14 years to 41 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Participants would be without illness or condition that could make follow-up, or compliance with study medication difficult.
  • Participants may have a prior diagnosis of Keratoconus, or may be diagnosed at the initial visit.
  • Participants should not have an eye diagnosis, other than Keratoconus, that could adversely influence the visual acuity.
  • These participants must not have had prior surgical procedure to treat Keratoconus, including collagen cross-linking, Intacs ring segments, or corneal transplantation.

Exclusion Criteria:

  • would exclude smokers and former-smokers.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Placebo Comparator: Placebo with Dietary Sources of Vitamins
Persons assigned to placebo, who obtain Vitamins A, C, E and Glutathione from dietary sources alone, and have not been on oral RDA supplementation, in the 1 month leading up the time of enrollment and throughout the study period.
Other: Placebo
Placebo pill
Combination product: Dietary Sources
From dietary sources of vitamins.
Active Comparator: Antioxidants(Vitamins A,C,E) plus GSH, plus Centrum
Persons assigned to the study medication, and are continuing the take an oral RDA supplementation, in the form of Centrum.
Other: Antioxidants (Vitamins A,C,E) plus GSH
Study medication would contain 500 milligrams of vitamin C, 400 International Units of vitamin E, and 15 milligrams of beta-carotene (the equivalent to 25,000 International Units of vitamin A).The study medication would also contain 1000mg of Glutathione (GSH).
Dietary supplement: Centrum
Centrum
Active Comparator: Antioxidants (Vitamins A,C, E) plus GSH
Persons assigned to the study medication alone, without oral RDA supplementation in the 1 month leading up the time of enrollment and throughout the study period.
Other: Antioxidants (Vitamins A,C,E) plus GSH
Study medication would contain 500 milligrams of vitamin C, 400 International Units of vitamin E, and 15 milligrams of beta-carotene (the equivalent to 25,000 International Units of vitamin A).The study medication would also contain 1000mg of Glutathione (GSH).
Active Comparator: Placebo plus Centrum
Persons assigned to placebo, who have been on oral RDA supplementation, who would continue to do so throughout the study.
Other: Placebo
Placebo pill
Dietary supplement: Centrum
Centrum

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Change in Visual Acuity Measured by Snellen Chart
Time Frame: Baseline to 24 months
Baseline to 24 months

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Change in cornea thickness as measured by video keratography
Time Frame: Baseline to 24 months
Baseline to 24 months
Plasma level of Vitamin A
Time Frame: Baseline to 24 months
Blood draws to look at plasma level of Vitamin A
Baseline to 24 months
Plasma level of Vitamin C
Time Frame: Baseline to 24 months
Blood draws to look at plasma level of Vitamin C
Baseline to 24 months
Plasma level of Vitamin E
Time Frame: Baseline to 24 months
Blood draws to look at plasma level of Vitamin E
Baseline to 24 months
Plasma level of Glutathione (GSH)
Time Frame: Baseline to 24 months
Blood draws to look at plasma level of GSH
Baseline to 24 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Miami

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Fight for Sight

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Ellen Koo, M.D., University of Miami

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Anticipated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
August 1, 2021

Primary Completion (Anticipated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
July 1, 2022

Study Completion (Anticipated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 1, 2023

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 25, 2016

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 7, 2016

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 11, 2016

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 16, 2021

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 11, 2021

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2021

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 20150646

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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