Collagen Crosslinking for Keratoconus - a Randomized Controlled Clinical Trial (CXL-RCT)

March 14, 2023 updated by: Wolf K Wonneberger, MD, Sahlgrenska University Hospital, Sweden
The purpose of this study is to determine whether corneal collagen crosslinking is effective in the treatment of progressive keratoconus.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

Keratoconus is a noninflammatory, asymmetrical, progressive corneal ectasia caused by biomechanical instability of the corneal stroma. Treatment modalities are primarily glasses or contact lenses. It has been estimated that one out of five patients will progress to such an extent that a corneal transplant is necessary to regain useful vision.

Corneal collagen crosslinking (CXL) is a treatment modality that intends to halt progression of keratoconus. This study investigates the efficacy av CXL in stabilizing the cornea in keratoconus by means of a randomized controlled clinical trial.

Participants are eligible for inclusion if progressive keratoconus is confirmed and the inclusion criteria are met. Follow-up after inclusion is at 1 week (treatment group), 1, 3, 6 and 12 months. Pre- and post-inclusion examinations include measurement of uncorrected distance visual acuity (UCDVA), best spectacle corrected distance visual acuity (BSCDVA), Scheimpflug-topography and slitlamp examination.

Study Type

Interventional

Enrollment (Actual)

36

Phase

  • Phase 3

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

  • Sweden
    • Västra Götalandsregionen
      • Mölndal, Västra Götalandsregionen, Sweden, 43180
        • Department of Ophthalmology, Sahlgrenska University Hospital

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

Ages Eligible for Study

18 years to 30 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Keratoconus diagnosis determined clinically and topographically (KISA%- index)

  • Significant progression is defined as change (increase) of Kmax by at least

    1D from baseline at 6 months and/or change (increase) of Sim-K-ast by at least 1D from baseline at 6 months. Kmax is defined as the steepest radius of curvature (either the maximum simulated K-reading or the maximum K-reading in the 3-mm zone or the 5-mm zone) of the anterior corneal surface that progressed the most during 6 months observation

  • Ability to stop contact lens (rigid and soft) wear at least two weeks prior to next exam
  • Signed written informed consent

Exclusion Criteria:

  • Age < 18 years
  • Pregnancy
  • Breast feeding
  • History of corneal surgery
  • History of ocular herpes simplex infection
  • Minimal corneal thickness < 300 micrometers
  • Recurrent corneal erosions
  • Other corneal (e g endothelial) or conjunktival diseases
  • Neurodermatitis
  • Severe forms av atopic disease
  • Collagenoses, autoimmune or other systemic disease
  • Systemic treatment with high doses of steroids
  • Severe scarring och striae of the cornea

Relative exclusion criteria:

  • Kmax > 58D
  • Minimal corneal thickness < 400 micrometers (a modified CXL-treatment will be used swelling the cornea before UV-illumination treatment).

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: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Corneal Collagen Crosslinking
The keratokonic eye which progresses most is included and randomized. Significant progression is defined in the eligibility criteria section. If randomized to the treatment arm the cornea is treated with collagen crosslinking as described below.
Device: Corneal Collagen Crosslinking
Keratoconic corneas that show significant progression as specified in the inclusion criteria section will receive one single treatment with CXL if randomized to the treatment arm. A treatment protocol based on 30 minutes dropping with riboflavin/dextran solution and 10 minutes UV-illumination treatment will be used.
Other Names:
  • Cross-Linking Procedure UV-X 2000
  • UV-X 2000 Illumination system
  • Innocross-R 0.1% dextran 20% solution
  • Innocross-R hypotonic riboflavin 0.1%
No Intervention: Control group
The keratokonic eye which progresses most is included and randomized to either the treatment group (CXL) or the control group.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Kmax
Time Frame: 12 months
Kmax is defined as the steepest radius of curvature of the anterior corneal surface. It is measured by Scheimpflug-topography (Pentacam, Oculus Inc.). An increase of less than 1 diopter (D) from baseline at 12 months is defined as non-progression.
12 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Sim-K-astigmatism
Time Frame: 12 months
Sim-K-astigmatism (Sim-K-ast) is defined as the absolute amount of anterior corneal astigmatism related to the Sim-Ks as measured by Scheimpflug-topography (Pentacam, Oculus Inc.). An increase of less than 1 D from baseline at 12 months is defined as non progression.
12 months
MRSE
Time Frame: 12 months
Manifest Refractive Spherical Equivalent. The spherical equivalent is calculated by algebraic addition of the spherical power and half the cylindrical power of an eye. An eye with a specific spherical equivalent power has the closest overall effect to a given toric lens. A decrease of less than 0.5 D from baseline at 12 months is defined as non-progression.
12 months
UCDVA
Time Frame: 12 months
UCDVA is defined as the uncorrected distance visual acuity measured with an Early Treatment of Diabetic Retinopathy Study (ETDRS)-chart and expressed in numbers of letters. A decrease of less than 5 letters (one line) from baseline at 12 months is defined as stable BCDVA.
12 months
BSCDVA
Time Frame: 12 months
BSCDVA is defined as the the best spectacle corrected distance visual acuity measured with an ETDRS-chart and expressed in numbers of letters. A decrease of less than 5 letters (one line) from baseline at 12 months is defined as stable BCDVA.
12 months

Collaborators and Investigators

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

Sponsor

Sahlgrenska University Hospital, Sweden

Collaborators

Göteborg University

Investigators

  • Study Chair: Madeleine Zetterberg, MD, PhD, Sahlgrenska University Hospital, Sweden
  • Study Director: Margareta Claesson, MD, PhD, Sahlgrenska University Hospital, Sweden

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)

May 1, 2012

Primary Completion (Anticipated)

April 1, 2024

Study Completion (Anticipated)

April 1, 2024

Study Registration Dates

First Submitted

May 21, 2012

First Submitted That Met QC Criteria

May 21, 2012

First Posted (Estimate)

May 23, 2012

Study Record Updates

Last Update Posted (Actual)

March 15, 2023

Last Update Submitted That Met QC Criteria

March 14, 2023

Last Verified

March 1, 2023

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • DNR-949-11

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.

Clinical Trials on Keratoconus

Clinical Trials on Corneal Collagen Crosslinking

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Azerbaijan

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe