Epi-on PiXL for the Treatment of Progressive Keratoconus.

Prospective Evaluation of Photorefractive Intrastromal Crosslinking (PiXL) Without Epithelium Debridement (Epi-on) in High Oxygen for Progressive Keratoconus.

The purpose of this study is to evaluate the efficacy, safety and postoperative ocular discomfort by individually customized Photorefractive intrastromal crosslinking (PiXL) without epithelium debridement in high oxygen environment (Epi-on) for progressive Keratoconus.

Study Overview

• Status: Active, not recruiting
• Conditions: Eye Diseases; Keratoconus; Corneal Crosslinking; Corneal Densitometry; Scheimpflug Photography; Corneal Disorder
• Intervention / Treatment: Procedure: Epi-on PiXL in high oxygen

Detailed Description

The study is designed as a prospective, open-label, nonrandomized trial involving participants of both genders aged 18-35 years with Keratoconus planned for routine corneal crosslinking at the Department of Ophthalmology, Umeå University Hospital, Umeå, Sweden.

The study includes 30 participants with unilateral Keratoconus, receiving Epi-on PiXL in high oxygen environment (n=30). All patients are informed about the procedures before consenting to participate in the study.

At baseline, before treatment, each eye is examined with slit-lamp microscopy, subjective refraction, determination of uncorrected (UCVA), low contrast visual acuity at 2.5 percentage contrast and 10 percentage contrast and best corrected (BSCVA) visual acuities using the LogMAR fast protocol and intraocular pressure (IOP) using Goldmann applanation tonometry. Under standardized, mesopic light conditions each eye is evaluated by keratometry readings and central corneal thickness, extracted from Schemipflug camera measurements, Pentacam HR® (Oculus, Inc. Lynnwood, WA) and AS-OCT (Fourier domain OCT CASIA2, Tomey Technology and vision, Germany).

Central corneal endothelial photographs are taken with the Topcon SP-IP specular microscope (Topcon Europe B.V., Capelle a/d Ijssel, the Netherlands) and total ocular wavefront is measured with iTrace (Tracey Technologies, Inc.).

Ocular discomfort is subjectively evaluated in each eye by a specific visual analogous rating scale at 4h, 8h, 12h, 24h and thereafter daily up to 1 week postoperatively.

All the above mentioned examinations are repeated at 1, 3, 6, 12 and 24 months after treatment. At 1 day and 1 week after treatment, solely UCVA, Auto refractor measurements, slit-lamp examination are evaluated.

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Sofie Näslund; Email: sofie.naslund@umu.se

Study Locations

• Sweden
  • Umeå, Sweden, 90185
    • Umeå University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 33 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients planned for corneal crosslinking.
• Progressive keratoconus documented with a consistent decrease of best corrected visual acuity with no other explanation, an unquestionable historical progression, or a progression documented with the Pentacam Scheimpflug camera with at least 2 of the following: progressive anterior and/or posterior corneal steepening and/or progressive corneal thinning and/or increased rate of corneal thickness change from the periphery to the center.
• A keratoconus diagnosis based on abnormal posterior elevation, abnormal corneal thickness distribution and clinical noninflammatory corneal thinning using the "Belin/Ambrósio enhanced ectasia" measurements of the Pentacam Scheimpflug camera.
• Minimum corneal thickness of 400 µm at the thinnest point before epithelial removal.
• 18-35 years of age
• No ocular abnormalities except keratoconus
• No previous ocular surgery
• No cognitive insufficiency interfering with the informed consent.

Exclusion Criteria:

• Age under 18 or over 35
• Any corneal abnormalities except keratoconus
• Pregnancy or lactation
• Previous ocular surgery
• Cognitive insufficiency

Study Plan

How is the study designed?

Design Details

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

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Epi-on PiXL in high oxygen; Photorefractive intrastromal corneal crosslinking without epithelium debridement during humidified high oxygen flow.

Procedure: Epi-on PiXL in high oxygen; After local anaesthetics, the keratoconus cornea is soaked in Riboflavin by repeated topical application during 10 minutes. A Riboflavin soaked sponge is used to lightly disrupt the epithelium tight junctions, without epithelium debridement. The cornea is illuminated with PiXL under 16:40 minutes during continuously delivery of humidified high oxygen via specific oxygen googles. The UV-dosage is individually customized based upon Kmax; for < 45 Diopters (D) 7.2J/cm^2 will be used; for 45-50D 10J/cm^2 will be used; for > 50D 15 J/cm^2 will be used.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Uncorrected Distance Visual Acuity (UDVA)	Change from baseline in Uncorrected Distance Visual Acuity	1, 3, 6, 12 and 24 months after treatment.
Keratometry readings	Change from baseline in Keratometry readings, Kmean (average), K1 (flat meridian), K2 (steep meridian) and Kmax (steepest radius of curvature) assessed with the Pentacam HR Scheimpflug camera	1, 3, 6, 12 and 24 months after treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective Ocular Discomfort Scores	Change in a Ocular Discomfort Visual Analogous Scale after treatment.	4, 8h and 1, 2, 3, 4, 5, 6 and 7 days after treatment.
Manifest Refractive Spherical Equivalent (MRSE)	Change from baseline in Manifest Refractive Spherical Equivalent	1, 3, 6, 12 and 24 months after treatment.
Corneal Endothelial cell density (ECC)	Change from baseline in corneal endothelial cell density	12 and 24 months after treatment
Best Spectacle Distance Visual Acutiy (BSCVA)	Change from baseline in Best Spectacle Distance Visual Acutiy	1, 3, 6, 12 and 24 months after treatment.

Collaborators and Investigators

• Sponsor: Umeå University
• Collaborators: Glaukos Corporation
• Investigators: Principal Investigator: Anders Behndig, Department of Clinical Sciences/Ophthalmology, Umeå University

Study record dates

Study Major Dates

• Study Start (Actual): March 20, 2019
• Primary Completion (Estimated): February 5, 2026
• Study Completion (Estimated): February 5, 2026

Study Registration Dates

• First Submitted: December 9, 2020
• First Submitted That Met QC Criteria: December 9, 2020
• First Posted (Actual): December 16, 2020

Study Record Updates

• Last Update Posted (Actual): December 20, 2023
• Last Update Submitted That Met QC Criteria: December 19, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Keratoconus; Corneal Diseases
• Other Study ID Numbers: PIXLKC-II

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