Accelerated Corneal Collagen Crosslinking for Keratoconus and Ectasia Using Pulse or Continuous UV-A Light

Sponsor

Cornea and Laser Eye Institute (Other)

Overall Status

Recruiting

CT.gov ID

NCT05027295

Collaborator

(none)

170

Enrollment

Location

Arms

Anticipated Duration (Months)

3.6

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Corneal collagen crosslinking has been demonstrated as an effective method of reducing progression of both keratoconus and post-refractive corneal ectasia, as well as decreasing the steepness of the cornea in these pathologies.

Performing an accelerated CXL procedure with pulsed UVA light may increase the oxygenation of the cornea, which may improve the crosslinking efficacy.

Condition or Disease	Intervention/Treatment	Phase
Keratoconus Corneal Ectasia	Drug: riboflavin ophthalmic solution Drug: riboflavin ophthalmic solution	Phase 3

Detailed Description

This is a prospective, single-site study to analyze the use of continuous vs pulsed UVA light after removal of the epithelium for the collagen crosslinking procedure for keratoconus and post-refractive corneal ectasia. In the standard crosslinking treatment, the cornea is treated with a continuous UVA light treatment with a power of 3mW/cm2 for 30 minutes. CXL treatment can potentially be performed in a shorter period of time by increasing the power of the UVA light and decreasing the exposure time, while maintaining the same total energy delivered to the cornea. This study will compare the efficacy and safety of accelerated crosslinking using either a continuous or pulsed UVA treatment. One group will be randomized to be treated with 12mW/cm2 of continuous UVA light treatment for 7.5 minutes and the other group will be treated with 12mW/cm2 of pulsed UVA light treatment for 15 minutes.

The primary efficacy parameter that will be evaluated over time is maximum keratometry (Kmax) in the randomized eyes for each treatment group. The secondary efficacy parameter is to determine if the two treatment groups are equivalent in their mean Kmax change at 6 months after treatment compared with baseline.

Study Design

Study Type:

Interventional

Anticipated Enrollment :

170 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

A Randomized Study to Evaluate the Safety and Efficacy of Corneal Collagen Crosslinking Performed With Continuous vs Pulsed UVA Light for Reducing Corneal Curvature in Eyes With Keratoconus and Post-refractive Corneal Ectasia

Actual Study Start Date :

Jul 30, 2021

Anticipated Primary Completion Date :

Jul 1, 2023

Anticipated Study Completion Date :

Jul 1, 2025

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Continuous UVA Riboflavin administration one drop every two minutes with administration of 12mW/cm2 of continuous UVA light for 7.5 minute exposure time	Drug: riboflavin ophthalmic solution Administration of riboflavin one drop every 2 minutes during administration of continuous UVA light for 7.5 minutes.
Active Comparator: Pulsed UVA Riboflavin administration one drop every two minutes with administration of 12mW/cm2 of pulsed UVA light for 15 minute exposure time	Drug: riboflavin ophthalmic solution Administration of riboflavin one drop every 2 minutes during administration of pulsed UVA light for 15 minutes

Arm

Intervention/Treatment

Active Comparator: Continuous UVA

Riboflavin administration one drop every two minutes with administration of 12mW/cm2 of continuous UVA light for 7.5 minute exposure time

Drug: riboflavin ophthalmic solution

Administration of riboflavin one drop every 2 minutes during administration of continuous UVA light for 7.5 minutes.

Active Comparator: Pulsed UVA

Riboflavin administration one drop every two minutes with administration of 12mW/cm2 of pulsed UVA light for 15 minute exposure time

Drug: riboflavin ophthalmic solution

Administration of riboflavin one drop every 2 minutes during administration of pulsed UVA light for 15 minutes

Outcome Measures

Primary Outcome Measures

Maximum keratometry [6 months]
The change in maximum keratometry (Kmax) from baseline will be evaluated at 6 months

Secondary Outcome Measures

Mean keratometry [6 months]
Determine whether the two treatment groups are equivalent in their mean keratometry (meanK) change at 6 months post treatment compared with baseline.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

18 years of age or older having a diagnosis of keratoconus or corneal ectasia after corneal refractive surgery
Presence of central or inferior corneal steepening on the Pentacam map
Axial topography consistent with keratoconus or post-surgical corneal ectasia
Contact lens wearers only: removal of contact lenses for the required period of 1 week prior to the screening refraction
Signed written informed consent
Willingness and ability to comply with schedule for follow-up visits

Exclusion Criteria:

Eyes classified as either normal, atypical normal, or keratoconus suspect on the severity grading scheme
Corneal pachymetry measuring 300 microns or less at the thinnest point measured by Pentacam in the eye(s) to be treated
Previous ocular condition (other than refractive error) in the eye(s) to be treated that may predispose the eye for future complications, for example:

History of corneal disease (e.g. herpes simplex, herpes zoster keratitis, recurrent corneal erosion syndrome, corneal melt, corneal dystrophy, etc.
Clinically significant scarring in the CXL treatment zone

A history of chemical injury or delayed healing in the eye(s) to be treated
Pregnancy (including plan to become pregnant) or lactation during the course of the study
A known sensitivity to study medications
Patients with nystagmus or any other condition that would prevent a steady gaze during the CXL treatment or other diagnostic tests
Patients with current condition that, in the investigator's opinion, would interfere with or prolong epithelial healing