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

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

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01699087
Enrollment
176
Registered
2012-10-03
Start date
2012-08-31
Completion date
2015-07-31
Last updated
2019-09-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Astigmatism, Myopia

Keywords

PRK, myopia, astigmatism

Brief 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.

Detailed 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.

Interventions

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.

DEVICEALLEGRETTO WAVE EYE-Q excimer laser system

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

Sponsors

Alcon Research
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

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

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Eyes With a BSCVA Worse Than 20/40 (for Eyes With BSCVA of 20/20 or Better Preoperatively) at Refractive StabilityMonth 6 (post second eye surgery)Visual acuity with correction was assessed monocularly using the ETDRS chart at 4 meters under photopic conditions .
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 PreoperativelyMonth 6 (post second eye surgery)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.
Percentage of Eyes Achieving Manifest Refraction Spherical Equivalent (MRSE) Within ± 1.0 D of Zero at Refractive StabilityMonth 6 (post second eye surgery)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.
Percentage of Eyes Achieving MRSE Within ± 0.5 D of Zero at Refractive StabilityMonth 6 (post second eye surgery)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.
Percentage of Eyes Achieving Manifest Refractive Cylinder Within ± 1.0 D of Zero at Refractive StabilityMonth 6 (post second eye surgery)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.
Percentage of Eyes Achieving Manifest Refractive Cylinder Within ± 0.5 D of Zero at Refractive StabilityMonth 6 (post second eye surgery)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.
Percentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsUp to Month 24 (post second eye surgery)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.
Cumulative Incidence of Ocular Serious Adverse Events by EyeUp to Month 24 (post second eye surgery)Participants were followed for the duration of the study, an expected average of 24 months.
Percentage of Eyes With BSCVA Decrease of ≥ 2 Lines From Baseline at Refractive StabilityMonth 6 (post second eye surgery)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).
Percentage of Eyes With > 2.0 D of Induced Manifest Refractive Cylinder Magnitude, as Compared to Baseline, at Refractive StabilityMonth 6 (post second eye surgery)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.

Participant flow

Recruitment details

Participants were recruited from 8 investigative sites located in the United States.

Pre-assignment details

Of the 176 participants enrolled, 15 did not meet inclusion and exclusion criteria and were exited prior to treatment as screen failures.

Participants by arm

ArmCount
PRK ALLEGRETTO
Photorefractive keratectomy (PRK) surgery using the ALLEGRETTO WAVE EYE-Q excimer laser system for myopic wavefront-optimized ablation
161
Total161

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyLost to Follow-up7
Overall StudyScreen failure (prior to treatment)15
Overall StudyUnable to make future visits2

Baseline characteristics

CharacteristicPRK ALLEGRETTO
Age, Continuous31.5 years
STANDARD_DEVIATION 7.4
Region of Enrollment
United States
161 participants
Sex: Female, Male
Female
72 Participants
Sex: Female, Male
Male
89 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
0 / 176123 / 161
serious
Total, serious adverse events
0 / 1766 / 161

Outcome results

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.

Time frame: Up to Month 24 (post second eye surgery)

Population: ITT

ArmMeasureGroupValue (NUMBER)
PRK ALLEGRETTOCumulative Incidence of Ocular Serious Adverse Events by EyeCorneal infiltrates2 eyes
PRK ALLEGRETTOCumulative Incidence of Ocular Serious Adverse Events by EyeCorneal oedema1 eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes Achieving Manifest Refraction Spherical Equivalent (MRSE) Within ± 1.0 D of Zero at Refractive Stability99.7 percentage of eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes Achieving Manifest Refractive Cylinder Within ± 0.5 D of Zero at Refractive Stability92.7 percentage of eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes Achieving Manifest Refractive Cylinder Within ± 1.0 D of Zero at Refractive Stability99.0 percentage of eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes Achieving MRSE Within ± 0.5 D of Zero at Refractive Stability93.3 percentage of eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: Intent to treat (ITT)

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage 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 Preoperatively100 percentage of eyes
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.

Time frame: Up to Month 24 (post second eye surgery)

Population: ITT

ArmMeasureGroupValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsWeek 1 to Month 190.9 percentage of eyes
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsMonth 1 to Month 395.6 percentage of eyes
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsMonth 3 to Month 699.7 percentage of eyes
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsMonth 6 to Month 9100 percentage of eyes
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsMonth 9 to Month 1299.7 percentage of eyes
PRK ALLEGRETTOPercentage of Eyes That Have a Change of ≤ 1.0 D in MRSE and Manifest Refractive Cylinder Between Consecutive Scheduled VisitsMonth 12 to Month 24100 percentage of eyes
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.

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes With > 2.0 D of Induced Manifest Refractive Cylinder Magnitude, as Compared to Baseline, at Refractive Stability0.0 percentage of eyes
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 .

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes With a BSCVA Worse Than 20/40 (for Eyes With BSCVA of 20/20 or Better Preoperatively) at Refractive Stability0.0 percentage of eyes
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).

Time frame: Month 6 (post second eye surgery)

Population: ITT

ArmMeasureValue (NUMBER)
PRK ALLEGRETTOPercentage of Eyes With BSCVA Decrease of ≥ 2 Lines From Baseline at Refractive Stability0.0 percentage of eyes

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026