- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT03197272
Advanced Cross Linking for Low-grade Myopia (PiXLO2)
Non-invasive Phototherapeutic Intrastromal Corneal Collagen Crosslinking (PiXL) for Low-grade Myopia
Study Overview
Detailed Description
The study is designed as a prospective, single-masked intraindividually comparing randomized controlled trial involving healthy volunteers ≥18 years of age of both genders with mild myopia, performed at the Department of Clinical Sciences / Ophthalmology, Umeå University Hospital, Umeå, Sweden. The study involves 23 persons with a myopia of -0.5 to -2.5 diopters (D) and astigmatism of ≤0.75 D. All participants are treated with phototherapeutic intrastromal corneal collagen cross-linking (PiXL) without epithelial debridement (epi-on), after topical riboflavin. For myopia of less than 1.0D, 10 J/cm2 will be used, for higher levels of myopia 15J/cm2 will be used, and the treatment involves continuous delivery of oxygen around the eye using an oxygen mask to achieve an oxygen concentration of ≥90% during treatment. Participants will be randomized to receive ultraviolet (UV) light according to PiXL Protocol A in one eye and PiXL Protocol B in the other, which is masked to the participant. Both eyes will be treated during the same visit.
Protocol A: UV irradiation in a central 4 mm homogenous zone of the cornea. Protocol B: UV irradiation in a central ring-shaped 4 mm area of the cornea. Patients are randomized utilizing a computer list of unique random numbers between 1 and 23; an even number will be treated with a homogeneous zone in the right eye; an uneven number with a homogeneous zone in the left eye. All patients are informed about the procedures and provide oral and written consent before inclusion in the study.
At baseline, before treatment, each eye is evaluated with slit-lamp examination, subjective refraction, determination of uncorrected (UCVA) and best corrected (BSCVA) visual acuities using the LogMAR fast protocol and intraocular pressure (IOP) using Goldmann applanation tonometry. Each eye is photographed using the "25 pictures" program with the Pentacam HR® (Oculus, Inc. Lynnwood, WA) under standardized, mesopic light conditions. Keratometry readings, central corneal thickness and the average corneal densitometry values (corneal light backscatter), expressed as standardized gray scale units, GSU) is determined with the Pentacam HR®. Central corneal endothelial photographs are taken with the Topcon SP-2000P specular microscope (Topcon Europe B.V., Capelle a/d Ijssel, the Netherlands), and the corneal endothelial cell count is calculated from a cluster of 25 cells from each photograph.
All the above mentioned investigations are repeated at 1, 3, 6,12 and 24 months after the treatment. At 1 week after treatment, UCVA is registered and a slit-lamp examination, a subjective comparison of discomfort and visual performance in each eye and an autorefractometer measurement are performed. One day after treatment the latter 3 examinations are performed.
Study Type
Enrollment (Actual)
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
-
Umeå, Sweden, 901 85
- Department of Clinical Sciences/Ophthalmology, Umeå University
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- 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.
Exclusion Criteria:
- History of or current ocular 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.
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Randomized
- Interventional Model: Single Group Assignment
- Masking: Single
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
---|---|
Experimental: PiXL Protocol A
PiXL treatment with UV irradiation in a central 4 mm homogenous zone of the cornea.
For myopia of less than 1.0D, 10 J/cm2 will be used, for higher levels of myopia 15J/cm2 will be used.
|
Phototherapeutic intrastromal corneal collagen cross-linking (PiXL) performed in a high-oxygen environment without corneal epithelial debridement, for treatment of mild myopia.
|
Active Comparator: PiXL Protocol B
PiXL treatment with UV irradiation in a central ring-shaped 4-mm area of the cornea.
A central 2-mm zone is left untreated, and the energy is higher towards the periphery of the ring-shaped area, reaching its maximum at 2 mm from the corneal centre.
For myopia of less than 1.0D, a maximum of 10 J/cm2 will be used, for higher levels of myopia a maximum of 15J/cm2 will be used.
|
Phototherapeutic intrastromal corneal collagen cross-linking (PiXL) performed in a high-oxygen environment without corneal epithelial debridement, for treatment of mild myopia.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
Change from baseline in uncorrected visual acuity
Time Frame: 1, 3, 6 and 12 months after treatment
|
Change from baseline in distance uncorrected visual acuity
|
1, 3, 6 and 12 months after treatment
|
Change from baseline in spherical equivalent
Time Frame: 1, 3, 6 and 12 months after treatment
|
Change from baseline in spherical equivalent on subjective distance refraction
|
1, 3, 6 and 12 months after treatment
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
Change from baseline in corneal endothelial cell density
Time Frame: 12 months after treatment
|
Change from baseline in central corneal endothelial cell density
|
12 months after treatment
|
Collaborators and Investigators
Sponsor
Collaborators
Investigators
- Principal Investigator: Anders Behndig, MD, PhD, Department of Clinical Sciences/Ophthalmology, Umeå University, Umeå, Sweden
Study record dates
Study Major Dates
Study Start (Actual)
Primary Completion (Actual)
Study Completion (Actual)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Actual)
Study Record Updates
Last Update Posted (Actual)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- PiXLMYOP-I
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
Studies a U.S. FDA-regulated device product
product manufactured in and exported from the U.S.
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 Myopia
-
He Eye HospitalNot yet recruiting
-
University of BradfordCoopervision, Inc.; University of HuddersfieldNot yet recruiting
-
Visioneering Technologies, IncRecruitingMyopiaUnited States, Canada, Hong Kong, Singapore
-
University Eye Hospital, FreiburgRecruiting
-
Shanghai 10th People's HospitalCompletedMyopia | Myopia, ProgressiveChina
-
Tianjin Eye HospitalActive, not recruiting
-
Tianjin Eye HospitalCompleted
-
Sultan Qaboos UniversityChristian Medical College, Vellore, IndiaUnknown
-
Peking University People's HospitalUnknownProgressive MyopiaChina
-
Shanghai Eye Disease Prevention and Treatment CenterNot yet recruiting
Clinical Trials on PiXL
-
Umeå UniversityGlaukos CorporationActive, not recruiting
-
Umeå UniversityGlaukos CorporationCompletedEye Diseases | Keratoconus | Corneal Disease | Corneal Crosslinking | Corneal Biomechanics | Corneal Densitometry | Scheimpflug PhotographySweden
-
Umeå UniversityGlaukos CorporationActive, not recruitingEye Diseases | Keratoconus | Corneal Crosslinking | Corneal Densitometry | Scheimpflug Photography | Corneal DisorderSweden