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Trial registered on ANZCTR


Registration number
ACTRN12619000773134p
Ethics application status
Submitted, not yet approved
Date submitted
5/05/2019
Date registered
24/05/2019
Date last updated
24/05/2019
Date data sharing statement initially provided
24/05/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Influences of Viscosity of Lubricating Eye Drops on Orthokeratology Treatment Outcomes
Scientific title
Influences of Viscosity of Lubricating Eye Drops on Treatment Outcomes in Ortho-K contact lens wearers.
Secondary ID [1] 297932 0
N/A
Universal Trial Number (UTN)
N/A
Trial acronym
N/A
Linked study record
N/A

Health condition
Health condition(s) or problem(s) studied:
Anterior Eye Health 312322 0
Refractive Error 312474 0
Condition category
Condition code
Eye 310888 310888 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study aims to determine whether the thickness (viscosity) of lubricating eye drops influences orthokeratology treatment outcomes. The primary outcomes to be measured are anterior eye health and comfort; secondary outcomes such as change in eye prescription and uncorrected vision will also be explored.

Eye drops used will be the thinner carboxymethyl cellulose 0.25% (Theratears) (Advanced Vision Research) and thicker carboxymethyl cellulose 1% (Theratears Liquid Gel) (Advanced Vision Research) or carboxymethyl cellulose 1% (Lumecare Singles Carmellose) (Contact Lens Australia). The choice for the thicker lubricant will solely be based on availability when the study commences but all participants will receive the same thick lubricant.

Participants will be given the thicker lubricating eye drop to be placed, at random, either in the left eye or right eye. They will be instructed to place 1 drop before inserting their OK lenses at night and 1 drop before removing the OK lenses in the following morning which will be repeated for 1 week whilst filling in a follow-up questionnaire at home. The thinner lubricating eye drop will be given to the fellow eye and the same instructions are given. The eye drops are to be applied topically and participants will be using their own prescribed OK lenses.

After 1 week, they will revisit the researchers for Visit 2 and commence the 1 week washout period. After this period, where the participants are told to not use any of the given eye drops, they will be given a new set of lubricating eye drops which swaps the eye drops over to the other eye, completing the cross-over study design.

In order to ensure the participants completes and follows the instructions set out by the research team, the participants will be required to fill out a follow-up questionnaire after the removal of their OK lenses each day. This questionnaire contains questions such as time of insertion/removal, vision and subjective comfort which will be collected after each visit. Additional procedures to ensure the protocol is followed is by re-explaining the instructions and to collect any remaining lubricants after each visit.
Intervention code [1] 314189 0
Treatment: Drugs
Comparator / control treatment
The active control in the study will be the eye receiving the thinner carboxymethyl cellulose 0.25% (Theratears) (Advanced Vision Research)
Control group
Active

Outcomes
Primary outcome [1] 319751 0
Proportion of participants with a change in corneal staining by 1 grade according to CCLRU scale.
Timepoint [1] 319751 0
1. Baseline result 1 (taken prior to commencement of treatment)
2. Result 1 (after 1 week of treatment) (primary endpoint)
3. Baseline result 2 (after wash-out period prior to commencement of cross-over)
4. Result 2 (after 1 week of treatment) (primary endpoint)
Primary outcome [2] 320098 0
Proportion of participants with a change in subjective comfort measured by a visual analogue scale in the follow-up questionnaire designed specifically for the study.
Timepoint [2] 320098 0
1. Baseline result 1 (taken prior to commencement of treatment)
2. Result 1 (after 1 week of treatment) (primary endpoint)
3. Baseline result 2 (after wash-out period prior to commencement of cross-over)
4. Result 2 (after 1 week of treatment) (primary endpoint)
Secondary outcome [1] 369417 0
Proportion of participants with a change in refractive error of at least 0.25D measured by manual phoropter refraction and auto-refraction.
Timepoint [1] 369417 0
1. Baseline result 1 (taken prior to commencement of treatment)
2. Result 1 (after 1 week of treatment) (secondary endpoint)
3. Baseline result 2 (after wash-out period prior to commencement of cross-over)
4. Result 2 (after 1 week of treatment) (secondary endpoint)
Secondary outcome [2] 370530 0
Proportion of participants with a change in visual acuity by 0.02 (per letter) measured by LogMAR chart.
Timepoint [2] 370530 0
1. Baseline result 1 (taken prior to commencement of treatment)
2. Result 1 (after 1 week of treatment) (secondary endpoint)
3. Baseline result 2 (after wash-out period prior to commencement of cross-over)
4. Result 2 (after 1 week of treatment) (secondary endpoint)

Eligibility
Key inclusion criteria
- At least 18 years of age
- Have worn the same pair of orthokeratology lenses regularly for at least 1 month
- Good understanding of and ability to communicate using the English language
- Willing to comply with use of ocular lubricants involved and visit schedule
- No known allergy to ocular lubricants
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- Currently under the treatment of any eye disease (whether that be anterior or posterior eye involvement) except refractive error corrections
- Use of oral or topical medications that may alter eye findings
- Any previous ocular injuries, eye conditions or eye surgeries
- Has worn soft contact lenses in the past week

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)
- Assigning each participant to a patient number (Participant 1, Participant 2, etc.)
- The student investigators will prepare the different combinations of ocular lubricants into organised bags which are numbered. The number will correspond with the participant’s number (E.g. Bag 1 will be for Participant 1). There will be an equal number of thicker and thinner lubricating eye drops in each bag.
- The chief and co-investigator will be tasked to randomise and assign combinations of ocular lubricants for each participant. The lubricating eye drops will be concealed by first removing any labels from the original packaging and relabelled with “R” for right eye and “L” for left eye at random by using https://www.random.org/lists/. The chief and co-investigator will then place the relabelled lubricating eye drops back into the bag.
- The student investigators will be masked to conduct the rest of the research and the eye drops given to each participants will be at random.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software via website (https://www.random.org/lists/)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Crossover
Other design features
N/A
Phase
Phase 3 / Phase 4
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis
In a similar study conducted by Carracedo Et. Al. 2018, their sample size of n = 20 concluded no difference in the following: Tear break up time, Best corrected visual acuity, Refractive error, Mean corneal curvature.
From these above points, we can reasonably sure that their sample size was able to raise a conclusive result. Without the need to repeat this study, our primary outcome will be corneal staining which had a standard deviation difference of 0.30. Therefore, including a 30% dropout rate we will require n = 13 as a sample size (calculated with PS: Power and Sample Size, Version 3.1.6).

Recruitment
Recruitment status
Not yet recruiting
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] 26282 0
2052 - Unsw Sydney

Funding & Sponsors
Funding source category [1] 302449 0
University
Name [1] 302449 0
University of New South Wales
Address [1] 302449 0
The University of New South Wales
Kensington, NSW, Australia, 2052
Country [1] 302449 0
Australia
Primary sponsor type
Individual
Name
Ms Kuan-Li Lily Ho
Address
UNSW Optometry Clinic
Rupert Myers Building
Gate 14, North Wing, Barker St
Kensington NSW 2052
Sydney
Country
Australia
Secondary sponsor category [1] 302793 0
None
Name [1] 302793 0
N/A
Address [1] 302793 0
N/A
Country [1] 302793 0
Other collaborator category [1] 280646 0
Individual
Name [1] 280646 0
Dr. Vinod Maseedupally
Address [1] 280646 0
UNSW Optometry Clinic
Rupert Myers Building
Gate 14, North Wing, Barker St
Kensington NSW 2052
Sydney
Country [1] 280646 0
Australia

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 303116 0
The University of New South Wales Research Ethics Committee
Ethics committee address [1] 303116 0
The University of New South Wales
Kensington, NSW, Australia, 2052
Ethics committee country [1] 303116 0
Australia
Date submitted for ethics approval [1] 303116 0
08/04/2019
Approval date [1] 303116 0
Ethics approval number [1] 303116 0
N/A

Summary
Brief summary
The aim of this study is to determine whether the thickness of lubricating eye drops for the front surface of the eye influences orthokeratology (OK) contact lens treatment outcomes. The primary outcomes to be measured are anterior eye health and comfort; the secondary outcomes of vision (eye prescription and how well an OK wearer sees) will also be explored with non-contact instruments.

The participant, who is an existing OK lenses wearer, will be required to use their own lenses along with two lubricating eye drops that will be given to them by the researchers. These drops will be used once before inserting their lenses at night and once again before removing them.

The participants will be required to visit the research clinic and researchers (UNSW Optometry Clinic, Kensington, NSW, Australia 2052) once a week for a total of 4 visits throughout the study. After the 2nd visit, the participants will undergo a wash-out period where they will be instructed to not use the provided lubricating eye drops. In this period, the participants have the opportunity to schedule their 3rd and 4th visit to their earliest convenience. Therefore, the participants can finish the study as quick as 1 month after applying.
Trial website
N/A
Trial related presentations / publications
N/A
Public notes
N/A

Contacts
Principal investigator
Name 92534 0
Ms Kuan-Li Lily Ho
Address 92534 0
UNSW Optometry Clinic
Rupert Myers Building
Gate 14, North Wing, Barker St
Kensington NSW 2052
Sydney
Country 92534 0
Australia
Phone 92534 0
+61 (2) 9385 4624
Fax 92534 0
Email 92534 0
lily.ho@unsw.edu.au
Contact person for public queries
Name 92535 0
Ms Kuan-Li Lily Ho
Address 92535 0
UNSW Optometry Clinic
Rupert Myers Building
Gate 14, North Wing, Barker St
Kensington NSW 2052
Sydney
Country 92535 0
Australia
Phone 92535 0
+61 (2) 9385 4624
Fax 92535 0
Email 92535 0
lily.ho@unsw.edu.au
Contact person for scientific queries
Name 92536 0
Ms Kuan-Li Lily Ho
Address 92536 0
UNSW Optometry Clinic
Rupert Myers Building
Gate 14, North Wing, Barker St
Kensington NSW 2052
Sydney
Country 92536 0
Australia
Phone 92536 0
+61 (2) 9385 4624
Fax 92536 0
Email 92536 0
lily.ho@unsw.edu.au

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?
Study protocol
Informed consent form
Ethical approval
Summary results
No Results