Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12618000717257
Ethics application status
Approved
Date submitted
6/04/2018
Date registered
1/05/2018
Date last updated
10/05/2019
Date data sharing statement initially provided
10/05/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
An evaluation of contact lens and phase plate designs incorporating a novel surface shape to allow clear distance and near vision.
Scientific title
Phase step optics contact lens and phase plates designed for presbyopic correction and its association with visual performance and corneal aberrations in adults.
Secondary ID [1] 294471 0
none
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Presbyopia 307233 0
Condition category
Condition code
Eye 306350 306350 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This trial will be a masked, randomised testing of up to 15 contact lens and/or phase plate prototypes with phase-step optics and a control lens. “Phase-step optics” is a type of surface shape that can be applied to a contact lens or phase plates to impart both far and near vision. The visual and functional assessment of participants wearing these lenses and phase plates will be compared with conventional control contact lenses. In addition, the study will investigate for associations between various baseline parameters like pupil size, corneal aberrations, ocular aberrations and visual functional performance.
Participants will undergo a baseline examination in the initial visit. This visit will comprise auto-refraction, subjective refraction with visual acuity measurement and ocular assessment with a slit-lamp bio-microscope (a specialized microscope for viewing the eye).
Contact lenses and/or phase plates will be trialled in each of the following two visits. The contact lenses will either be made of Polymethylmethacrylate (PMMA) or Hydroxyethylmethacrylate (HEMA or conventional hydrogel) material. Both of these materials are standard formulations of well-established contact lens materials. Their composition are defined by their chemical formulation as produced by the manufacturer of the materials.
PMMA and hydrogel lenses behave differently on eye. One major difference is the presence of a ‘tear lens’. This is a microscopic volume of the wearer’s tears that resides between the back of a contact lens and the front of the cornea. In a PMMA lens, the tear lens has substantial optical power. In the hydrogel, the tear lens power is negligible. By testing both PMMA and hydrogel, we can determine the impact the tear lens optical power may have on the performance of phase-step contact lenses.

The contact lenses and phase plates will have varied optical designs (surface shape). The optical design of the lenses will vary but not be limited to phase-step features such as varied groove numbers, varied spacing between grooves, varied groove heights in order to achieve different optical-visual outcomes. The maximum number of grooves on a lens shall be 24, and the maximum relative sag height (departure from the base surface geometry of the lens) shall be less than 5 microns. The criteria for this will be based on optical performance characteristics such as through-focus point-spread function and extended depth of focus range.

Fitting visits will be performed by unmasked investigators and comprise contact lens fitting, assessment of contact lens visual acuity and assessment of contact lenses on eye with a slit-lamp biomicroscope. If the participant is a presbyope requiring reading spectacles of +1.50 dioptres (D) and above, no drops will be used. When this is not the case, to control the accommodation of the participant, the following will be administered: 1 drop benoxinate and 2 drops of 1% tropicamide (each of these drops separated by 5 min). This was the chosen regimen as it gives a good cycloplegic effect while being much shorter acting compared to cyclopentolate.

Each of the contact lens visits will take a maximum of 2 hours in duration. All patients will trial all types of lenses in both eyes. The duration of each lens wear will be up to an hour.

At the completion of each lens trial, the patient will fill out a subjective ratings of vision questionnaire utilising a 1-10 numeric rating scale. The second visit will occur at least 24 hours after the first visit.

All contact lenses will be fitted and all assessments will be carried out by a registered optometrist.
Intervention code [1] 300764 0
Treatment: Devices
Comparator / control treatment
Contact lens or phase plate of the same material without the phase step surface shape, or a commercially available multifocal contact lens in the market, or baseline measurements with the best corrected prescription.
Control group
Active

Outcomes
Primary outcome [1] 305364 0
Visual acuity at high and low contrast will be assessed using electronic logMAR charts at 6 m, 70cm, 50 cm and 40 cm.
Timepoint [1] 305364 0
The primary outcome will be assessed at baseline and 20 minutes after contact lens insertion, for each contact lens type. No waiting period is required in the case of phase plates.
Secondary outcome [1] 344959 0
Subjective rating of clarity of vision (at distance, intermediate and near) will be assessed with a questionnaire utilising numeric rating scales (1- 10 in 1-point steps). The questions have been designed specifically for this study.
Timepoint [1] 344959 0
These secondary outcomes will be assessed 1 hour after each contact lens fitting, at the completion of contact lens testing or phase plate testing.
Secondary outcome [2] 344960 0
Subjective rating of ghosting (at distance, intermediate and near) will be assessed with a questionnaire utilising numeric rating scales (1- 10 in 1-point steps). The questions have been designed specifically for this study.
Timepoint [2] 344960 0
These secondary outcomes will be assessed 1 hour after each contact lens fitting or at the completion of phase plate testing.
Secondary outcome [3] 346032 0
Subjective rating of comfort will be assessed with a questionnaire utilizing numeric rating scales (1- 10 in 1-point steps). The questions have been designed specifically for this study.
Timepoint [3] 346032 0
These secondary outcomes will be assessed 1 hour after each contact lens fitting or at the completion of the phase plate testing.
Secondary outcome [4] 346033 0
Contact lens fit will be evaluated. This will be assessed using slit-lamp bio-microscopy.
Timepoint [4] 346033 0
These secondary outcomes will be assessed 40 minutes after each contact lens fitting.
Secondary outcome [5] 346134 0
Contact lens fit will be evaluated. This will be assessed using slit-lamp bio-microscopy (direct obeservation and photographing the contact lens on the eye).
Timepoint [5] 346134 0
These secondary outcomes will be assessed 40 minutes after each contact lens fitting.

Eligibility
Key inclusion criteria
• Age 18 or greater
• Able to read and comprehend English
• Have vision correctable to at least 6/9 or better in at least one eye
• Have ocular health findings considered to be “normal” and which would not prevent the participant from safely wearing contact lenses.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• Existing active eye conditions
• Any systemic disease that adversely affects ocular health e.g. diabetes
• Recent ocular trauma or ocular surgery that is not resolved/stable or may affect vision
• Prior refractive surgery (LASIK, LASEK, RK, PRK, IOL etc.)
• Contraindications to contact lens wear.
• Known allergy or intolerance to ingredients in any of the clinical trial products.
• Use of or a need for any systemic medication or topical medications which may alter normal ocular findings
• Inability to focus for prolonged periods (e.g., due to strabismus, nystagmus, etc.)
• Pregnant women, breast-feeding women, or women who plan to become pregnant during the course of the study.


Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created through www.randomization.com
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
12/05/2019
Actual
Date of last participant enrolment
Anticipated
10/07/2019
Actual
Date of last data collection
Anticipated
10/07/2019
Actual
Sample size
Target
20
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 299095 0
Other
Name [1] 299095 0
Brien Holden Vision Institute
Country [1] 299095 0
Australia
Primary sponsor type
Other
Name
Brien Holden Vision Institute
Address
Level 4, Rupert Myers Building Gate 14, Barker
Street University of New South Wales, NSW
2052
Country
Australia
Secondary sponsor category [1] 298345 0
None
Name [1] 298345 0
Address [1] 298345 0
Country [1] 298345 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 300030 0
HREC University of New South Wales
Ethics committee address [1] 300030 0
UNSW Sydney NSW 2052
Ethics committee country [1] 300030 0
Australia
Date submitted for ethics approval [1] 300030 0
30/03/2016
Approval date [1] 300030 0
08/04/2016
Ethics approval number [1] 300030 0
HC16028

Summary
Brief summary
he aim of this project is to investigate patient and design-specific parameters on the efficacy of phase-step optics contact lenses and phase plates, as a solution for presbyopia. Presbyopia is an age related condition, usually initially affecting people over the age of 45, impacting the ability of the eye to focus sharply at near distances. The knowledge obtained will allow the construction of a matrix of predictors of performance to guide and optimise lens design and visual performance.
Our primary hypothesis is that clinical testing will allow for measurements of varied phase-step contact lenses and phase plate designs in eyes of varied parameters. This will allow for correlations and validation with the theoretical data obtained from ray tracing analysis and in vitro physical model eye measurements.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 82318 0
Prof Arthur Ho
Address 82318 0
Brien Holden Vision Institute
Level 4, Rupert Myers Buildin g Gate 14, Barker
Street University of New South Wales, NSW
2052
Country 82318 0
Australia
Phone 82318 0
+61293857453
Fax 82318 0
+61293857401
Email 82318 0
a.ho@brienholdenvision.org
Contact person for public queries
Name 82319 0
Prof Arthur Ho
Address 82319 0
Brien Holden Vision Institute
Level 4, Rupert Myers Buildin g Gate 14, Barker
Street University of New South Wales, NSW
2052
Country 82319 0
Australia
Phone 82319 0
+61293857453
Fax 82319 0
+61293857401
Email 82319 0
a.ho@brienholdenvision.org
Contact person for scientific queries
Name 82320 0
Prof Arthur Ho
Address 82320 0
Brien Holden Vision Institute
Level 4, Rupert Myers Buildin g Gate 14, Barker
Street University of New South Wales, NSW
2052
Country 82320 0
Australia
Phone 82320 0
+61293857453
Fax 82320 0
+61293857401
Email 82320 0
a.ho@brienholdenvision.org

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.