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Trial registered on ANZCTR


Registration number
ACTRN12618000298213
Ethics application status
Approved
Date submitted
31/01/2018
Date registered
28/02/2018
Date last updated
18/01/2022
Date data sharing statement initially provided
9/07/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Evaluation of the clinical performance of multifocal orthokeratology contact lenses in young healthy adults
Scientific title
Evaluation of the short-term lens fitting performance of novel multifocal orthokeratology contact lens designs in young healthy adults
Secondary ID [1] 293922 0
Nil known
Universal Trial Number (UTN)
U1111-1208-7599
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Progressing mild childhood myopia 306413 0
Condition category
Condition code
Eye 305501 305501 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study will investigate the short-term fitting performance and corneal reshaping efficacy of multifocal orthokeratology (MFOK) contact lenses. Participants who meet eligibility requirements will take part in one, two or all three parts of the study, which will be conducted by a research team of qualified optometrists. In Part 1 the static and dynamic fitting characteristics of MFOK contact lenses with different parameters will be evaluated in a series of 15-minute lens wearing trials, over a maximum 1 hour period. Topical anaesthetic drops (0.4% oxybuprocaine) may be used to minimise discomfort after insertion and during fitting assessment of trial contact lenses. In Part 2, subjects will wear MFOK lenses in both eyes overnight only (7-8 hours per night) for up to 4 nights to evaluate lens fit in the closed eye. In Part 3, participants will wear MFOK lenses designed to correct their myopia, overnight only (7-8 hours per night) for up to 28 days, to evaluate lens fit and corneal reshaping efficacy.
All contact lenses will be made of Boston XO material (Dk 100 ISO/Fatt units). The research team will initially insert lenses into the subjects' eyes at the School of Optometry and Vision Science at the University of New South Wales. For parts 2 and 3, subjects will receive face-to-face instructions on how to insert, remove, clean and maintain the MFOK lenses so that they can safely wear the study lenses during the required wearing period. Participant compliance with the study protocol in parts 2 and 3 will be monitored by text messages from the research team every second day during the lens wearing period.
Intervention code [1] 300192 0
Treatment: Devices
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 304633 0
Contact lens centration, as determined by central treatment zone centration (x, y; mm) quantified from corneal topographic map
Timepoint [1] 304633 0
Part 2: after 1 and 4 (primary outcome) nights of overnight lens wear
Part 3: after 1, 7, 14 and 28 (primary outcome) nights of overnight lens wear
Primary outcome [2] 304634 0
Corneal topographic changes: mean change in corneal power (D) and corneal radius of curvature (mm) at different corneal locations, measured using the Medmont corneal topographer
Timepoint [2] 304634 0
Part 3: after 1, 7, 14 and 28 (primary outcome) nights of overnight lens wear
Primary outcome [3] 304673 0
Contact lens centration (x, y; mm) measured using high magnification clinical microscopy
Timepoint [3] 304673 0
Part 1: after 15 minutes of open-eye lens wear
Secondary outcome [1] 342633 0
Central refraction, using standard optometric techniques and the Shin-Nippon NVision K-5001 autorefractor
Timepoint [1] 342633 0
Part 2: after 1 and 4 nights of overnight lens wear
Part 3: after 1, 7, 14 and 28 nights of overnight lens wear
Secondary outcome [2] 342634 0
Ocular aberrations, using the IVS Discovery aberrometer
Timepoint [2] 342634 0
Part 3: after 1, 7, 14 and 28 nights of overnight lens wear
Secondary outcome [3] 372342 0
Objective peripheral refraction, in horizontal and vertical meridians, at 5 degree steps out to 30 degrees, using the Shin-Nippon NVision K-5001 autorefractor.
Timepoint [3] 372342 0
Part 3: at baseline and after 28 nights of overnight lens wear

Eligibility
Key inclusion criteria
Eligibility criteria include:
- Aged 18 to 40 years
- Refractive error between +2.50 and -6.00D (parts 1 and 2); between -2.00 and -5.00D (part 3); corneal toricity <1.50D (all parts)
- No history of rigid contact lens wear
- Soft contact lens wearers willing to discontinue lens wear for at least 24 hours before participation
- Good ocular health with no history of ocular trauma or surgery
- Good general health and no medications which may influence ocular health
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Potential participants will not be enrolled if they show:
- Any contraindications for rigid contact lens wear
- Anisometropia >0.75D
- Ocular pathology or active ocular surface disease
- Strabismus or amblyopia
- History of adverse reactions to eye drops or topical anaesthetics
- Not willing or able to comply with the treatment and followup schedule

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not performed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
NA
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Study Part 1: Due to the exploratory nature of the initial part of the study, sample size determination is not a relevant approach. Based on our prior experience with evaluating OK lens fits, we anticipate that a total of 10 participants will be sufficient for us to reach our preliminary conclusions.
Study Part 2: Using data from previous research, to conduct a study that is able to detect a 0.5mm decentration in treatment zone with the MFOK lenses, with a study power of 80% and a 5% level of statistical significance and taking into consideration a 25% drop out rate, 15 subjects will be required.
Study Part 3: Using data from previous research, to conduct a study that is able to detect a difference of 0.1 D in mid-peripheral corneal refractive power, with a study power of 0.80 at the 5% level of statistical significance and taking into consideration a 20% drop out rate, 14 subjects will be required.

Recruitment
Recruitment status
Stopped early
Data analysis
Data analysis is complete
Reason for early stopping/withdrawal
Participant recruitment difficulties
Other reasons/comments
Other reasons
Clinical trial has stopped early due to COVID-19 related delays in recruitment.
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment postcode(s) [1] 18733 0
2052 - Unsw Sydney

Funding & Sponsors
Funding source category [1] 298551 0
Commercial sector/Industry
Name [1] 298551 0
CooperVision Inc
Country [1] 298551 0
United States of America
Primary sponsor type
Commercial sector/Industry
Name
CooperVision Inc
Address
5870 Stoneridge Drive, Suite 1, Pleasanton CA 94588
Country
United States of America
Secondary sponsor category [1] 297696 0
None
Name [1] 297696 0
Address [1] 297696 0
Country [1] 297696 0
Other collaborator category [1] 280848 0
Commercial sector/Industry
Name [1] 280848 0
ProCornea Nederland BV
Address [1] 280848 0
Kollergang 9, NL - 6961 LZ Eerbeek, The Netherlands
Country [1] 280848 0
Netherlands

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299520 0
University of New South Wales Human Research Ethics Committee
Ethics committee address [1] 299520 0
University of New South Wales
Sydney, NSW 2052
Ethics committee country [1] 299520 0
Australia
Date submitted for ethics approval [1] 299520 0
05/02/2018
Approval date [1] 299520 0
08/06/2018
Ethics approval number [1] 299520 0
HC180050

Summary
Brief summary
Conventional orthokeratology (OK) lenses are specialised rigid contact lenses that are worn overnight during sleep in order to reshape the front surface of the eye (the cornea) to temporarily correct mild to moderate degrees of refractive error, most commonly short-sightedness or myopia. OK lenses produce subtle changes in the curvature and power of the cornea, in the order of microns of change, when worn overnight. When the lens is removed on awakening, the reshaped cornea is now able to correct the vision of the patient during the day. The reshaping effect is temporary, and the cornea returns to its original shape and power if overnight lens wear is discontinued. Conventional OK lenses produce a single central zone of altered corneal power, and are usually used for refractive correction of simple myopia.

Multifocal OK (MFOK) lenses differ from conventional OK lens designs in that the back surface design of the lens is modulated to produce a multifocal effect on corneal shape. In other words, the lens is designed to induce annular regions of alternating corneal flattening and steepening which result in concentric rings of varying corneal surface power. Contact lens designers claim that this produces a multifocal defocus effect on the neural layer of the back of the eye, or the retina, which is potentially useful for correcting presbyopia (poor reading vision), and for reducing myopic progression in children.

There are no published data on the fitting performance of MFOK lenses of differing designs. For a MFOK lens to be effective for its optical purpose, in correcting or controlling refractive errors, the corneal reshaping effect must be centred over the pupil, and the corneal reshaping induced by overnight lens wear must produce the desired changes in corneal power. The research proposed here will investigate these aspects of MFOK lens performance, to determine the potential for various designs of MFOK lens to be useful for their refractive purpose in long term use.


Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 80702 0
Prof Helen Swarbrick
Address 80702 0
School of Optometry and Vision Science
Gate 14, Barker St
Rupert Myers Building, North Wing
University of New South Wales
Sydney NSW 2052
Country 80702 0
Australia
Phone 80702 0
+61 2 9385 4373
Fax 80702 0
+61 2 9313 6243
Email 80702 0
Contact person for public queries
Name 80703 0
Helen Swarbrick
Address 80703 0
School of Optometry and Vision Science
Gate 14, Barker St
Rupert Myers Building, North Wing
University of New South Wales
Sydney NSW 2052
Country 80703 0
Australia
Phone 80703 0
+61 2 9385 4373
Fax 80703 0
+61 2 9313 6243
Email 80703 0
Contact person for scientific queries
Name 80704 0
Helen Swarbrick
Address 80704 0
School of Optometry and Vision Science
Gate 14, Barker St
Rupert Myers Building, North Wing
University of New South Wales
Sydney NSW 2052
Country 80704 0
Australia
Phone 80704 0
+61 2 9385 4373
Fax 80704 0
+61 2 9313 6243
Email 80704 0

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


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.