Photorefractive Intrastromal Corneal Crosslinking as a Treatment for Low Grade Myopia

NCT03987880 | Completed

• 1 other identifier: PiXLMYOP-II
• Study Type: interventional
• Target: 27
• Locations: 1 country
• Sites: 1

Brief Summary

To assess the improvement in refractive error and the corneal endothelial safety with a customized corneal crosslinking treatment regimen for low grade myopia. The study compares two treatment protocols, a 4.0-mm central ring-shaped zone with a 3.5-mm central ring-shaped zone in high oxygen environment without corneal epithelial debridement.

Conditions

Myopia; Corneal Crosslinking; Refractive Errors; Eye Diseases

Outcome Measures

Primary Outcomes (2)

• Change from baseline in uncorrected visual acuity

  Change from baseline in distance uncorrected visual acuity

  1, 3, 6, 12 and 24 months after treatment

• Change from baseline in spherical equivalent

  Change from baseline in spherical equivalent on subjective distance refraction

  1, 3, 6, 12 and 24 months after treatment

Secondary Outcomes (2)

• Change from baseline in corneal endothelial cell density

  12 and 24 months after treatment

• Change from baseline in best corrected visual acuity

  1, 3, 6, 12 and 24 months after treatment

Study Arms (2)

4.0 mm zone

ACTIVE COMPARATOR

PiXL treatment with UV irradiation in a central 4.0-mm ring-shaped zone of the cornea. The area consist of three rings with a central 2-mm zone that is left untreated. The energy is higher towards the periphery of the ring-shaped area, reaching its maximum at 2-mm from the corneal centre. Pulsed UV-light, 1s on / 1s off; 30mW. For myopia of less than 0.75D, 10 J/cm2 is used, for higher levels of myopia 15J/cm2 is used.

Procedure: 4.0 mm treatment

3.5 mm zone

EXPERIMENTAL

PiXL treatment with UV irradiation in a central ring-shaped 3.5-mm zone of the cornea, with a central 1.5 mm zone that is left untreated. The illumination area consists of three rings, where the outer and inner ring are thinner than the middle ring. The maximum energy is distributed in the middle ring. Pulsed UV-light, 0.5s on / 1s off; 45mW. For myopia of less than 0.75D, a maximum of 10 J/cm2 is used, for higher levels of myopia a maximum of 15J/cm2 is used.

Procedure: 3.5 mm treatment

Interventions

4.0 mm treatment PROCEDURE

PiXL treatment with UV irradiation in a central 4.0-mm ring-shaped zone of the cornea.

4.0 mm zone

3.5 mm treatment PROCEDURE

PiXL treatment with UV irradiation in a central 3.5-mm ring-shaped zone of the cornea.

3.5 mm zone

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Spherical equivalent on distance subjective refraction between -0.50D and -2.50D.
• Astigmatism ≤ 0.75D
• Stable myopia. Maximum change in refraction of 0.50D in the last 2 years.
• Best corrected visual acuity of at least 0.00 logMAR (ETDRS chart).
• Thinnest pachymetry reading ≥ 440 μm.
• No previous ocular surgery.
• No cognitive insufficiency interfering with the informed consent.

You may not qualify if:

• History of or current condition, disease, surgery or medication with ocular effects that could affect the outcomes of the treatment.
• Allergy to any substance or device used in the study.
• Cognitive insufficiency interfering with the informed consent.

Sponsors & Collaborators

• Umeå University: lead
• Glaukos Corporation: collaborator

Study Sites (1)

Department of Clinical Sciences/Ophthalmology, Umeå University

Umeå, 901 85, Sweden

Location

MeSH Terms

Conditions

Myopia; Refractive Errors; Eye Diseases

Interventions

Therapeutics

Study Officials

• Anders Behndig, MD, PhD

  Department of Clinical Sciences/Ophthalmology, Umeå University, Umeå, Sweden

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: The participants are not aware which eye will receive the 4.0-mm ring-shaped zone treatment and which eye will receive the 3.5-mm ring-shaped zone treatment.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: Prospective, single-masked intraindividually comparing randomized controlled trial. Participants will be randomized to receive ultraviolet (UV) light according to protocol A in one eye and protocol B in the other, which is masked to the participant. Both eyes will be treated during the same visit. Participants are randomized utilizing a computer list of unique random numbers between 1 and 27; an even number will be treated with the 4.0-mm zone in the right eye; an uneven number with the 4.0-mm zone in the left eye.

Study Record Dates

• First Submitted: June 12, 2019
• First Posted: June 17, 2019
• Study Start: January 22, 2018
• Primary Completion: October 15, 2020
• Study Completion: October 15, 2020
• Last Updated: December 10, 2020

Record last verified: 2020-12

Data Sharing

• IPD Sharing: Will not share

Locations

SE (1)