A Safety and Effectiveness Study of PRK Using the ALLEGRETTO WAVE® EYE-Q Excimer Laser System

Myopia Clinical Trial

Official title:

Prospective Safety and Effectiveness Study of PRK for Myopia With or Without Astigmatism Using the ALLEGRETTO WAVE® EYE-Q Excimer Laser System

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01699087
• Other study ID #: C-10-084
• Status: Completed
• Phase: N/A
• Start date: August 2012
• Est. completion date: July 2015

Study information

• Verified date: May 2018
• Source: Alcon Research
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to evaluate the safety and effectiveness of the ALLEGRETTO WAVE EYE-Q excimer laser system for the reduction of myopia with or without astigmatism in subjects undergoing photorefractive keratectomy (PRK) treatment.

Description:

This was a prospective, multi-center, single group study. Subjects underwent bilateral PRK in which the second eye was treated no sooner than 1 week and no later than 30 days after the first eye's PRK treatment. Subjects were followed for 2 years after surgery.

The protocol underwent 4 amendments. The key differences between the protocol versions were clarifications of the planned analyses and adverse event reporting procedures. There were no changes in the inclusion and exclusion criteria or non-adverse event related study assessments between the protocol versions 1-5.

Refractive stability of manifest refraction spherical equivalent (MRSE) and manifest refractive cylinder was defined as established when:

• At least 95% of the treated eyes had a change ≤ 1.0 diopter between manifest refractions performed at any 2 manifest refractions at least 3 months apart

• The mean rate of change, as determined by a paired analysis, was ≤ 0.5 diopter per year (0.04 D/month) over the same time period

• The mean rate of change decreased monotonically over time, with a projected asymptote of zero or a rate of change attributable to normal aging

• The 95% confidence interval for the mean rate of change included zero or a rate of change attributable to normal aging.

Refractive stability was assessed for pairs of visits within an interval and was defined to occur at the latter time point of the first interval at which stability was achieved.

In the final amendment to the protocol, 3 secondary objectives were made co-primary in response to Agency comments. All endpoints and analyses were modified to match.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 176
• Est. completion date: July 2015
• Est. primary completion date: July 2015
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Subjects desiring refractive correction of myopia up to -6.00 Diopter (D) sphere with or without astigmatism 0 to -3.00 D and up to -6.00 D manifest refraction spherical equivalent (MRSE) at the spectacle plane measured by manifest refraction;

• Minimum best spectacle corrected visual acuity (BSCVA) in the treated eye of 20/25;

• Uncorrected visual acuity (UCVA) 20/40 or worse in the treated eye;

• Less than 0.75 D spherical equivalent (SE) difference between cycloplegic and manifest refractions;

• Stable refraction (within ± 0.5 D), as determined by MRSE for a minimum of 12 months prior to surgery;

• Demonstrated stable refraction for contact lens wearers, as specified in protocol;

• Signed informed consent document;

• Willing and able to comply with schedule for follow-up visits;

• Other protocol-defined inclusion criteria may apply.

Exclusion Criteria

• Females who are pregnant, lactating, or planning a pregnancy during the time course of the study, or have another condition associated with the fluctuation of hormones that could lead to refractive changes;

• Participation in other clinical trials during this study;

• Acute or chronic disease or illness that would increase the operative risk or confound the outcomes of the study;

• Dry eye syndrome as determined by the short questionnaire for dry eye syndrome;

• Systemic medications that may confound the outcome of the study or increase the risk to the subject by affecting wound healing or tissue repair, including, but not limited to steroids, antimetabolites, immune response modifying drugs, etc.;

• Nystagmus or any other condition that would prevent a steady gaze during the PRK treatment or other diagnostic tests;

• Ocular condition that may predispose the subject to future complications;

• Previous intraocular or corneal surgery;

• Subjects who desire to have monovision;

• A known sensitivity to medications used for study procedures, including PRK;

• Presence or history of any condition or finding that makes the subject unsuitable as a candidate for PRK or study participation or may confound the outcome of the study, in the opinion of the Investigator;

• Other protocol-defined exclusion criteria may apply.

Related Conditions & MeSH terms

• Astigmatism
• Myopia

Intervention

Procedure:
• Photorefractive keratectomy (PRK)
In this corneal surgical procedure, the outer corneal epithelial layer will be removed, after which the corneal stroma will be reshaped by excimer laser ablation to reduce or eliminate refractive errors.

Device:
• ALLEGRETTO WAVE EYE-Q excimer laser system
The ALLEGRETTO WAVE EYE-Q excimer laser system is used for corneal stroma reshaping during PRK surgery

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
Alcon Research

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Percentage of Eyes Achieving Uncorrected Visual Acuity (UCVA) of 20/40 or Better at Refractive Stability in Eyes With Best Spectacle-corrected Visual Acuity (BSCVA) of 20/20 or Better Preoperatively	Visual acuity, with and without correction, was assessed monocularly using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart at 4 meters under photopic conditions . The with-correction assessment was made with the manifest refraction at 4 meters.	Month 6 (post second eye surgery)
Primary	Percentage of Eyes Achieving Manifest Refraction Spherical Equivalent (MRSE) Within ± 1.0 D of Zero at Refractive Stability	Manifest refraction spherical equivalent (MRSE) is calculated as follows: sphere + 1/2 cylinder. The sphere and cylinder values are from the manifest refraction assessment. The manifest refraction assessment was conducted monocularly with the ETDRS chart at 4 meters under photopic conditions using a phoropter.	Month 6 (post second eye surgery)
Primary	Percentage of Eyes Achieving MRSE Within ± 0.5 D of Zero at Refractive Stability	Manifest refraction spherical equivalent (MRSE) is calculated as follows: sphere + 1/2 cylinder. The sphere and cylinder values are from the manifest refraction assessment. The manifest refraction assessment was conducted monocularly with the ETDRS chart at 4 meters under photopic conditions using a phoropter.	Month 6 (post second eye surgery)
Primary	Percentage of Eyes Achieving Manifest Refractive Cylinder Within ± 1.0 D of Zero at Refractive Stability	Manifest refraction was performed monocularly under photopic lighting conditions using an ETDRS chart at 4 meters. The subject was manually refracted to his/her best correction using a phoropter.	Month 6 (post second eye surgery)
Primary	Percentage of Eyes Achieving Manifest Refractive Cylinder Within ± 0.5 D of Zero at Refractive Stability	Manifest refraction was performed monocularly under photopic lighting conditions using an ETDRS chart at 4 meters. The subject was manually refracted to his/her best correction using a phoropter.	Month 6 (post second eye surgery)
Primary	Percentage of Eyes That Have a Change of = 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled Visits	MRSE is calculated as sphere + 1/2 cylinder. The sphere and cylinder values are from the manifest refraction assessment. The manifest refraction assessment was conducted monocularly with the ETDRS chart at 4 meters under photopic conditions using a phoropter.	Up to Month 24 (post second eye surgery)
Primary	Cumulative Incidence of Ocular Serious Adverse Events by Eye	Participants were followed for the duration of the study, an expected average of 24 months.	Up to Month 24 (post second eye surgery)
Primary	Percentage of Eyes With BSCVA Decrease of = 2 Lines From Baseline at Refractive Stability	Visual acuity with correction was assessed monocularly using the ETDRS chart at 4 meters under photopic conditions . A decrease in 2 lines or more is considered clinically relevant (i.e. worse).	Month 6 (post second eye surgery)
Primary	Percentage of Eyes With a BSCVA Worse Than 20/40 (for Eyes With BSCVA of 20/20 or Better Preoperatively) at Refractive Stability	Visual acuity with correction was assessed monocularly using the ETDRS chart at 4 meters under photopic conditions .	Month 6 (post second eye surgery)
Primary	Percentage of Eyes With > 2.0 D of Induced Manifest Refractive Cylinder Magnitude, as Compared to Baseline, at Refractive Stability	Manifest refraction was performed monocularly under photopic lighting conditions using an ETDRS chart at 4 meters. The subject was manually refracted to his/her best correction using a phoropter. The cylinder value is from the manifest refraction assessment. The induced manifest refractive cylinder is the change in magnitude of cylinder compared to baseline.	Month 6 (post second eye surgery)

External Links

•   Results from the Novartis Clinical Trial Results Website