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Active, not recruitingNCT01112072CXLUpdated Feb 8, 2023

Corneal Collagen Crosslinking and Intacs for Keratoconus and Ectasia

A Phase 3 interventional study of Riboflavin in Keratoconus and Corneal Ectasia, sponsored by Cornea and Laser Eye Institute. Active, not recruiting at 1 site in United States. Open to participants aged 21 Years and older. Per ClinicalTrials.gov, last updated 2023-02-08.

Sponsored by Cornea and Laser Eye Institute · Phase 3, Interventional, and Treatment

From the registry’s dates

  • Primary completion was expected by Dec 2024, 1 year 11 months ago, but the record still lists the study as active, not recruiting.
Phase
Phase 3
Study type
Interventional
Enrollment
160
Allocation
Randomized
Ages
21 Years and older
Sex
All
01

Study summary

This study will determine the efficacy of corneal collagen crosslinking (CXL) combined with Intacs for the treatment of keratoconus and corneal ectasia. The goal of CXL is to decrease the progression of keratoconus, while Intacs has been shown to decrease corneal steepness in keratoconus. This study will attempt to determine the relative efficacy of the two procedures either performed at the same session versus CXL performed 3 months after Intacs.

Read the detailed description

The purpose of this is to ascertain the possible additive effect of the two treatments to both improve the quality of the corneal optics (i.e. improve corneal topography regularity) and to stabilize the cornea. Previous investigations have shown that Intacs surgery, indeed, does improve corneal topography and improve contact lens tolerance and spectacle corrected visual acuity, as well as uncorrected visual acuity in some patients. Investigations of CXL have shown the procedure not only to decrease keratoconus progression, but also to decrease the steepness of the cone and improve uncorrected and best corrected visual acuity in some cases. Since the mechanism of improvement differs between the procedures, this suggests a potential additive effect of the two on the patient's ultimate visual outcome. Thus, the patient would be afforded two potential benefits: (1) the potential of a more robust visual outcome and (2) stabilization of the keratoconic cornea on the longer term.

02

Conditions studied

  • Keratoconus
  • Corneal Ectasia

Keywords

  • keratoconus
  • corneal ectasia
  • collagen crosslinking
  • riboflavin
  • cornea
  • ultraviolet
03

In context

Keratoconus

313 studies on the registry are indexed under Keratoconus; 56 are open to participants now.

This study's planned enrollment of 160 is above the median of 40 across 205 interventional studies indexed under Keratoconus.

Browse Keratoconus studies →

Lead sponsor

Cornea and Laser Eye Institute is the lead sponsor of 10 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
21 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • 21 years of age or older
  • Having a diagnosis of keratoconus or corneal ectasia after corneal refractive surgery (e.g., LASIK, photorefractive keratectomy [PRK], or epi-LASIK)
  • Subjects who meet the manufacturer's nomogram recommendations for Intacs segments
  • Topography consistent with keratoconus or post-surgical corneal ectasia.
  • BSCVA worse than 20/20 (\<55 letters on ETDRS chart)

Exclusion criteria

Exclusion Criteria:

  • Eyes classified as either normal, atypical normal, or keratoconus suspect on the severity grading scheme.
  • Corneal pachymetry ≤ 400 microns at the thinnest point measured by Pentacam in the eye(s) to be treated when the isotonic riboflavin solution is used or ≤ 300 microns when the hypotonic riboflavin us used, provided that the corneal thickness after treatment with the hypotonic riboflavin solution is > 400 microns. Corneal pachymetry ≤ 450 microns at the proposed insertion site for the Intacs
  • Previous ocular condition (other than refractive error) in the eye(s) to be treated that may predispose the eye for future complications
  • History of corneal disease
  • History of chemical injury or delayed epithelial 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
  • Subjects with nystagmus or any other condition that would prevent a steady gaze during the CXL and Intacs treatment or other diagnostic tests.
  • Subjects with a current condition that, in the investigator's opinion, would interfere with or prolong epithelial healing.
05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
160 participants (estimated)

Study arms

  • Active comparator
    Intacs combined with CXL

    Intacs placement followed by collagen crosslinking with UV light and riboflavin

    Drug: Riboflavin

  • Active comparator
    Intacs followed by CXL

    Intacs placement, to be followed by corneal collagen crosslinking with UV light and riboflavin 3 months later

    Drug: Riboflavin

Interventions

  • DrugRiboflavin

    Corneal epithelium removed followed by riboflavin drop administration every 2 minutes for 30 minutes followed by UV light exposure with additional riboflavin administration every 2 minutes for 30 minutes. Subjects will be randomized to receive Intacs placement either immediately before CXL or 3 months before CXL.

    Also known as: Intracorneal Ring Segments, Cornea Collagen Crosslinking

06

What researchers measure

Primary outcomes

  1. Maximum keratometry

    Time frame: 1 year

Secondary outcomes

  1. Best Corrected Visual Acuity

    Time frame: 1 year

07

Study locations

1 site
08

Timeline

Tracking since Sep 25, 2026
Not marked actual or estimatedDates not marked actual or estimated

The record gives a start of Apr 2010, a primary completion of Dec 2024 and a completion of Dec 2025. It does not say whether these dates are actual or estimated.

How these figures are worked out, and which studies are left out of them.

Registered
Apr 26, 2010
First posted
Apr 28, 2010
Start
Apr 2010
Primary completionEst.
Dec 2024
CompletionEst.
Dec 2025
Last update
Feb 8, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Feb 8, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT01112072
Lead sponsor
Cornea and Laser Eye Institute
Responsible party
Sponsor
First posted
Apr 28, 2010
Start date
Apr 2010
Primary completion
Dec 2024 (estimated)
Completion
Dec 2025 (estimated)
Last update
Feb 8, 2023

Study contacts

Peter Hersh, M.D.
principal investigator · Cornea and Laser Eye Institute

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Feb 2023. You cannot join it, but the record below documents what was studied.

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Discussion

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Studies of the drug tested here: Riboflavin

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