AmetropiaNCT04698174
Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment
A study testing Transepithelial Photorefractive keratectomy (tPRK) without laser polishing, Transepithelial Photorefractive keratectomy (tPRK) with laser polishing and Standard Photorefractive keratectomy (PRK) in people with Ametropia, run by Bausch & Lomb Incorporated at 1 site in Philippines.
Trial summary
This is a prospective, comparative, randomized, controlled, single-blind, single-surgeon, single-center PMCF clinical study whereby participants undergoing refractive surgery for correction of ametropia will receive a transepithelial PRK (tPRK) and conventional PRK treatment in the contralateral eye. Read more about this study
- Who is it for?
- Ages 18 to 85 years
- Conditions the study is for
- Ametropia
- What is being tested?
- Transepithelial Photorefractive keratectomy (tPRK) without laser polishing, Transepithelial Photorefractive keratectomy (tPRK) with laser polishing and Standard Photorefractive keratectomy (PRK)
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 39 participants
- Where
- 1 sitePhilippines
- Study dates
- 2 Feb 2021to 21 Mar 2022
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Ametropia
- Myopic subjects with refractive spherical equivalent (MRSE) between -1.5D and -9.0D
- Hyperopic subjects with refractive spherical equivalent (MRSE) between +1.5D and +5.25D
- Signed informed consent form
Who cannot join
- Ocular comorbidity
- Subject taking systemic medications likely to affect wound healing such as corticosteroids or antimetabolites.
- Subjects who are known to be pregnant, lactating, or who plans to become pregnant over the medications used for standard tPRK.
- Subjects participating in any other ophthalmic clinical trial during this clinical study.
- Subjects with cognitive impairments or other vulnerable persons
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Prospective Clinical Study to Evaluate the Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment
This is a prospective, comparative, randomized, controlled, single-blind, single-surgeon, single-center PMCF clinical study whereby participants undergoing refractive surgery for correction of ametropia will receive a transepithelial PRK (tPRK) and conventional PRK treatment in the contralateral eye. To avoid bias in the clinical outcomes, the two PRK treatment options are randomized to the eyes of the patients based on ocular dominance. In addition, a 1:1 randomization is applied within the tPRK group to eyes with and without end-treatment laser polishing.
Both procedures, standard PRK and tPRK, are performed in a one-step procedure. The main difference between the procedures is, that in conventional PRK, the epithelium will be removed using alcohol, whereas in tPRK procedures, the epithelium will be removed by laser ablation.
- Conditions
- Ametropia
- Being tested
- Transepithelial Photorefractive keratectomy (tPRK) without laser polishing, Transepithelial Photorefractive keratectomy (tPRK) with laser polishing, Standard Photorefractive keratectomy (PRK)
- Medical subject headings
- Refractive Errors
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Transepithelial Photorefractive keratectomy (tPRK) without laser polishingProcedure or surgery
Transepithelial Photorefractive keratectomy (tPRK) with laser ablation of the corneal epithelium and stroma in a single-step procedure using the B+L Teneo 317 Model 2 Excimer Laser.
Transepithelial Photorefractive keratectomy (tPRK) with laser polishingProcedure or surgery
Transepithelial Photorefractive keratectomy (tPRK) using the B+L Teneo 317 Model 2 Excimer Laser with end-treatment laser polishing using a fixed thickness of the additional layer of 5 μm.
Standard Photorefractive keratectomy (PRK)Procedure or surgery
Conventional Photorefractive keratectomy (PRK) with alcohol-assisted epithelium ablation. Then the aspheric ablation profile will be performed using the B+L Teneo 317 Model 2 Excimer Laser.
| Study group | Role | What they receive |
|---|---|---|
| Transepithelial Photorefractive keratectomy (tPRK) without laser polishing | Experimental | Not described Receives: Procedure: Transepithelial Photorefractive keratectomy (tPRK) without laser polishing |
| Transepithelial Photorefractive keratectomy (tPRK) with laser polishing | Experimental | Not described Receives: Procedure: Transepithelial Photorefractive keratectomy (tPRK) with laser polishing |
| Standard Photorefractive keratectomy (PRK) | Active comparator | Not described Receives: Procedure: Standard Photorefractive keratectomy (PRK) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Absolute refractive predictability
Absolute refractive predictability is the absolute difference between intended and achieved Manifest Refraction Spherical Equivalent (MRSE) between eyes
Measured: 3 months follow up
Secondary outcomes (9)
Monocular Uncorrected Distance Visual Acuity (UDVA) under photopic light conditions
The visual acuity measurements will be assessed using Clinical Trial Suite (M\&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under photopic light conditions.
Measured: 3 months follow up
Monocular Uncorrected Distance Visual Acuity (UDVA) under mesopic light conditions
The visual acuity measurements will be assessed using Clinical Trial Suite (M\&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under mesopic light conditions.
Measured: 3 months follow up
Monocular Corrected Distance Visual Acuity (CDVA) under photopic light conditions
The visual acuity measurements will be assessed using Clinical Trial Suite (M\&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under photopic light conditions. Corrected means spectacle corrected.
Measured: 3 months follow up
Monocular Corrected Distance Visual Acuity (CDVA) under mesopic light conditions
The visual acuity measurements will be assessed using Clinical Trial Suite (M\&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under mesopic light conditions. Corrected means spectacle corrected.
Measured: 3 months follow up
Monocular Contrast Sensitivity
The contrast sensitivity test consists in assessing the possibility to distinguish the alternation of white and grey fringes of difference contrast with difference frequency.
Contrast sensitivity will be assessed under photopic and mesopic light conditions using Clinical Trial Suite (M\&S Technologies, Niles, IL, USA) device at 2.5 m.
Measured: 3 months follow up
Halo Photic phenomena
The amount and disturbance of photic halo side effects will be assessed by the Halo Simulator: With this software tool the particant mimics the individual vision perception by adjusting a typical night scene image with the intensity and size of halo. The simulator utilizes a numerical scale to quantify the size and intensity of halos, ranging from 0 (none), 25 (mild), 50 (moderate), 75 (severe) to 100 (very severe).
Measured: 3 months follow up
Glare Photic phenomena
The amount and disturbance of photic glare side effects will be assessed by the Glare simulator: With this software tool the particant mimics the individual vision perception by adjusting a typical night scene image with the intensity and size of glare. The simulator utilizes a numerical scale to quantify the size and intensity of glare, ranging from 0 (none), 25 (mild), 50 (moderate), 75 (severe) to 100 (very severe).
Measured: 3 months follow up
Corneal pain
The epithelial healing process after photorefractive keratectomy treatment often comes along with the perception of some corneal pain. To assess the pain level, the participants will receive a self-administered pain questionnaire to fill out every day from the day of the surgery until they return for the 6-9 days follow up visit. An 11-point scale will be used to rate the self-reporting of pain, where 0 is 'None' and 10 is the highest level of 'Severe'. Higher scores indicate higher level of pain.
Measured: 3 months follow up
Visual perception scale
To assess the visual perception level, the participants will receive a self-administered visual perception questionnaire to fill out every day from the day of the surgery until they return for the 6-9 days follow up visit. A 4-point scale will be used to rate the self-reporting of visual perception, with 1 = 'Clear' and 4 = 'Very Poor' vision. Higher scores indicate poorer visual perception.
Measured: 3 months follow up
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Jan 2021
- Study start2 Feb 2021
- Primary completion21 Mar 2022
- Study completion21 Mar 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for AmetropiaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 39 participants (actual)
Sponsor and investigators
- Lead sponsor
- Bausch & Lomb Incorporated
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Robert Ang, MD, Principal investigator, Asian Eye Institute
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04698174
- Sponsor's protocol ID
- BL1902
- Status last verified
- Mar 2022
- First submitted
- 30 Oct 2020
- Last updated
- 7 Oct 2022
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Ang RET. Transepithelial Versus Conventional PRK: A Randomized Controlled Study. Ophthalmol Ther. 2025 Jul;14(7):1567-1579. doi: 10.1007/s40123-025-01167-2. Epub 2025 May 30.
PubMed 40445504
Study at a glance
From the registry record, last updated by the sponsor on 7 Oct 2022. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prospective Clinical Study to Evaluate the Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment
- ClinicalTrials.gov ID
- NCT04698174
- Acronym / sponsor ID
- BL1902
- Conditions
- Ametropia
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 39 participants (actual)
- Lead sponsor
- Bausch & Lomb IncorporatedIndustry (pharma, biotech, devices)
- Study start
- 2 Feb 2021 (actual)
- Primary completion
- 21 Mar 2022 (actual)
- Study completion
- 21 Mar 2022 (actual)
- First posted
- 6 Jan 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a prospective, comparative, randomized, controlled, single-blind, single-surgeon, single-center PMCF clinical study whereby participants undergoing refractive surgery for correction of ametropia will receive a transepithelial PRK (tPRK) and conventional PRK treatment in the contralateral eye. To avoid bias in the clinical outcomes, the two PRK treatment options are randomized to the eyes of the patients based on ocular dominance. In addition, a 1:1 randomization is applied within the tPRK group to eyes with and without end-treatment laser polishing.
Both procedures, standard PRK and tPRK, are performed in a one-step procedure. The main difference between the procedures is, that in conventional PRK, the epithelium will be removed using alcohol, whereas in tPRK procedures, the epithelium will be removed by laser ablation.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Transepithelial Photorefractive keratectomy (tPRK) without laser polishing | Experimental | Procedure: Transepithelial Photorefractive keratectomy (tPRK) without laser polishing |
| Transepithelial Photorefractive keratectomy (tPRK) with laser polishing | Experimental | Procedure: Transepithelial Photorefractive keratectomy (tPRK) with laser polishing |
| Standard Photorefractive keratectomy (PRK) | Active comparator | Procedure: Standard Photorefractive keratectomy (PRK) |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Ametropia
- Myopic subjects with refractive spherical equivalent (MRSE) between -1.5D and -9.0D
- Hyperopic subjects with refractive spherical equivalent (MRSE) between +1.5D and +5.25D
- Signed informed consent form
Key exclusion criteria (5 listed)
- Ocular comorbidity
- Subject taking systemic medications likely to affect wound healing such as corticosteroids or antimetabolites.
- Subjects who are known to be pregnant, lactating, or who plans to become pregnant over the medications used for standard tPRK.
- Subjects participating in any other ophthalmic clinical trial during this clinical study.
- Subjects with cognitive impairments or other vulnerable persons
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Transepithelial Photorefractive keratectomy (tPRK) without laser polishingTransepithelial Photorefractive keratectomy (tPRK) with laser ablation of the corneal epithelium and stroma in a single-step procedure using the B+L Teneo 317 Model 2 Excimer Laser. | Procedure or surgery | Transepithelial Photorefractive keratectomy (tPRK) without laser polishing |
| Transepithelial Photorefractive keratectomy (tPRK) with laser polishingTransepithelial Photorefractive keratectomy (tPRK) using the B+L Teneo 317 Model 2 Excimer Laser with end-treatment laser polishing using a fixed thickness of the additional layer of 5 μm. | Procedure or surgery | Transepithelial Photorefractive keratectomy (tPRK) with laser polishing |
| Standard Photorefractive keratectomy (PRK)Conventional Photorefractive keratectomy (PRK) with alcohol-assisted epithelium ablation. Then the aspheric ablation profile will be performed using the B+L Teneo 317 Model 2 Excimer Laser. | Procedure or surgery | Standard Photorefractive keratectomy (PRK) |
Primary outcome
Absolute refractive predictability
Time frame: 3 months follow up
Absolute refractive predictability is the absolute difference between intended and achieved Manifest Refraction Spherical Equivalent (MRSE) between eyes
9 secondary outcomes
Monocular Uncorrected Distance Visual Acuity (UDVA) under photopic light conditions
Time frame: 3 months follow up
Monocular Uncorrected Distance Visual Acuity (UDVA) under mesopic light conditions
Time frame: 3 months follow up
Monocular Corrected Distance Visual Acuity (CDVA) under photopic light conditions
Time frame: 3 months follow up
Monocular Corrected Distance Visual Acuity (CDVA) under mesopic light conditions
Time frame: 3 months follow up
Monocular Contrast Sensitivity
Time frame: 3 months follow up
Halo Photic phenomena
Time frame: 3 months follow up
Glare Photic phenomena
Time frame: 3 months follow up
Corneal pain
Time frame: 3 months follow up
Visual perception scale
Time frame: 3 months follow up
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Oct 2022.
- Derived from this study: PubMed 40445504Ang RET. Transepithelial Versus Conventional PRK: A Randomized Controlled Study. Ophthalmol Ther. 2025 Jul;14(7):1567-1579. doi: 10.1007/s40123-025-01167-2. Epub 2025 May 30.
- Individual participant dataSharing planned: Undecided
Related trials for Ametropia
Active, not recruiting
Clinical Trial With Artiflex Presbyopic (Artiplus)
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Not yet recruiting
Comparison of Two Rotational Alignment Methods for Astigmatism Correction in SMILE Surgery
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Recruiting
The Impact of 'A Miss Is as Good as a Mile': Is Compensation Necessary for Minimal Ocular Deviation in Myopic Laser Surgery?
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Recruiting
Comparison of Low- Versus High-Level Angle Kappa Compensation Strategies in SMILE Using the VisuMax 800: A Randomized Clinical Trial
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Recruiting
A Study to Evaluate the Clinical Performance and Safety of UNICON Silicone Hydrogel Daily Disposable Soft Contact Lenses
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Robert Ang, MD principal investigator
Asian Eye Institute
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Transepithelial Photorefractive keratectomy (tPRK) without laser polishing, Transepithelial Photorefractive keratectomy (tPRK) with laser polishing and Standard Photorefractive keratectomy (PRK) in people with Ametropia, run by Bausch & Lomb Incorporated at 1 site in Philippines.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Oct 2022. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Philippines. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Absolute refractive predictability (time frame: 3 months follow up). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04698174, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Oct 2022.