Dietary Riboflavin (Vitamin B-2) and Cornea Cross-Linking

December 3, 2025 updated by: University of Missouri-Columbia
Corneal ectasia is characterized by irregularity and thinning of the cornea, causing the cornea to bulge forward and cause distorted vision and impaired visual acuity. Corneal ectasia is a complication after refractive (LASIK) surgery. It is also the primary problem in keratoconus, a gradually progressive inherited condition that typically is manifested in young adulthood, more commonly in women. Treatment approaches to stabilize the cornea's shape include rigid contact lenses, surgical implantation of stiff plastic intrastromal corneal ring segments, a collagen cross-linking procedure and, in severe cases, cornea transplantation. The collagen cross-linking procedure involves topical application of a concentrated riboflavin (vitamin B2) solution after the corneal epithelium is scraped, followed by ultraviolet (UV) light exposure. UV light stimulates riboflavin to form new bonds (cross links) between the cornea's connective tissue, giving the cornea additional strength to maintain its shape and prevent the need for transplantation. The cost of one treatment using this system is $2,500 to $3,500. A small prospective study including 7 patients with keratoconus was started on a trial of oral riboflavin and 15 minutes of natural sunlight exposure daily. These patients reported no adverse effects and preliminary results showed corneal stabilization and/or corneal flattening in all 7 patients It is hypothesized that dietary riboflavin and natural sunlight is as effective in corneal crosslinking as the currently FDA approved Avedro therapy. If the clinical study confirms the investigators' early observations of the benefits of this approach, coupled with animal studies that document corneal cross-linking, the investigators will have data to pursue funding for larger clinical and animal studies. This has the potential to save millions of dollars in health care costs and ease the burden of treatment in patients who require therapy to induce corneal cross-linking to stabilize the cornea's shape.

Study Overview

Status

Status

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

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.

Detailed Description

Corneal ectasia as a complication from refractive (LASIK) surgery as well as keratoconus is a slowly progressive condition that results in high patient morbidity. Treatment options aim to stabilize the shape of the cornea using rigid contact lenses, surgical insertion of stiff plastic intrastromal rings, corneal cross linking, and ultimately corneal transplant in severe patients. The recently FDA approved "Dresden Protocol" involves painful cornea scraping followed by application of concentrated Riboflavin, followed by immediate collagen cross linking with UV light exposure which results in shortening and thickening of the collagen fibrils, and therefore a stronger, stiffer cornea. Avedro has demonstrated an average cornea flattening (K max reduction) of 1.4 diopters and 1.7diopters in two different studies. The current cost of Avedro therapy is between $2500 -$3500 per treatment. This is considered to be an accepted medical procedure at this time and therefore is beginning to be covered by several insurance companies.To spare the patient the severe pain involved in the current procedure, and to avoid the high cost (Avedro is not covered by any medical insurance), the investigator started 7 patients with keratoconus from 2011-2015 in his private practice in Seattle on a trial of oral riboflavin (100 mg or 400 mg daily) and 15 minutes of sunlight exposure daily. No adverse effects have ever been reported with high-dose dietary riboflavin supplements. The results of this preliminary trial are remarkable. During follow-up from 6 months to 5 years, all 7 patients have had corneal stabilization and/or corneal flattening. One patient experienced flattening of the cornea by 1.5 Diopters, comparable to the best results of the Avedro system. A limited animal study was recently completed and published in Switzerland by Dr. Farhad Hafezi , M.D., PhD which was published in the Journal of Cataract & Refractive Surgery that confirmed corneal cross-linking occurs in response to riboflavin and UV exposure from the sun and proven to successfully crosslink. Our current clinical study would expand the promising preliminary findings to a larger sample size. This has the potential to save millions of dollars in health care costs and ease the burden of treatment in patients who require therapy to induce corneal cross-linking to stabilize the cornea's shape.

To date eye specialists in Brazil, Texas and other locations are beginning to treat patients with our protocol and finding similar successful results using 400 to 800mg dietary riboflavin and 15 to 45 minutes of sunlight exposure for a period of 3 to 6 months with successful results.

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

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
30

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.
  • Not Applicable

Contacts and Locations

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

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Florida
      • Tampa, Florida, United States, 33612
        • University of South Florida Department of Ophthalmology

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

12 years and older (Child, Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • patients identified as having keratoconus or post refractive cornea ectasia with astigmatism of 1.5 Diopters or greater.

Exclusion Criteria:

  • Known sensitivity to riboflavin, sunlight.
  • patients on medications with side effects of increased sunlight sensitivity should discuss participation with their prescribing provider prior to participation

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

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.
Experimental: Treatment with riboflavin
Patients will take 400 mg dietary riboflavin per day and go outside without sunglasses for 15 minutes per day to evaluate the effects of riboflavin B2 and natural UV light from sun exposure on cornea cross linking and stabilization of ectatic disease.
Dietary supplement: Dietary riboflavin
Dietary riboflavin is vitamin B2. It has been shown to be safe in children in the treatment of migraines at doses of 400 mg per day. There are no known documented side effects
Other Names:
  • Vitamin B2

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
Measure Description
Time Frame
Degree of corneal steepening
Time Frame: 6 months
Keratometry measures the degree of astigmatism of the cornea to monitor the degree of cornea steepening
6 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
Best corrected visual acuity
Time Frame: 6 months
Measures the best vision the patient is able to see at that time
6 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 Missouri-Columbia

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.
University of South Florida

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: John S Jarstad, MD, University of South Florida - Department of Ophthalmology

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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 (Actual)

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.
May 1, 2017

Primary Completion (Actual)

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.
March 8, 2021

Study Completion (Actual)

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 8, 2021

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).
October 13, 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.
March 23, 2017

First Posted (Actual)

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.
March 29, 2017

Study Record Updates

Last Update Posted (Estimated)

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.
December 10, 2025

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.
December 3, 2025

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.
December 1, 2025

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.
  • 2006390

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

No

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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