Effectiveness of the Defocus Incorporated Spectacle Lenses on Fast Progressing Myope

Study Overview
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Brief Summary
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The purpose of this study is to examine the efficacy and performance of the variant of Defocus Incorporated Spectacle lenses on controlling myopia progression in fast progressing myopic children.

Detailed Description
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The variant of Defocus Incorporated Spectacle lenses (DG2) is a multifocal spectacle lens that produces myopic defocus images and corrects distance refractive errors at the same time. Participants will be randomly allocated to either single vision lens group (control) or the variant of Defocus Incorporated Spectacle lens (DG2) group (treatment). After 12 months of lens wear, the SV lens prescribed to the control group will be replaced with the DG2 lens and be monitored for another 12 months. In parallel, the DG2 treatment groups will continue their corresponding intervention for 12 months. Their cycloplegic refraction and axial length will be monitored every 6 months over 2 years. The changes in refractive errors and axial length in two groups will be compared.

Official Title
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Effectiveness of the Defocus Incorporated Spectacle Lenses on Fast Progressing Myope: A Randomised Control Trial

Conditions
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Myopia

Intervention / Treatment
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* Other: Variant of Defocus Incorporated Spectacle lens (DG2)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: SER: -1.00D or below Documented history of fast progressing myopia, either in SER or AL SER progression: 0.50D/year or more AL elongation: 0.27mm/year or more Best-corrected monocular visual acuity (VA) in both eyes: 0.00 logMAR (equivalent) or better Acceptance of random group allocation and the masked study design Anisometropia of 1.50 D or less Astigmatism of 2.00 D or less Exclusion Criteria: Strabismus and binocular vision abnormalities Ocular and systemic abnormalities Prior experience of myopia control

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 12 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants will be randomly allocated to either control (wearing single vision lenses) group or treatment (DG2 lens) group for first 12 months. After 12 months, the SV lens prescribed to the control group will be replaced with the DG2 lens and be monitored for another 12 months. In parallel, the DG2 treatment groups will continue their corresponding intervention for 12 months.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Single vision lens group<br>Subjects in single vision lens group will receive a pair of single vision lenses for the first year of study. They will then receive a pair of DG2 lenses for the second year of the study. | |
| Experimental: DG2 lens group<br>Subjects in DG2 lens group will receive a pair of DG2 lenses over the 2-year study. | Other: Variant of Defocus Incorporated Spectacle lens (DG2)<br>* DG2 is a variant of Defocus Incorporated Spectacle lens that corrects the distance refraction and provides myopic defocus simultaneously<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cycloplegic refraction change in spherical equivalent refraction (SER) | Cycloplegic SER (in diopter) will be measured using an open field autorefractor. Change in SER with cycloplegia from the baseline over a first 12-month period and a 12-month period of follow-up will be measured | Baseline, 1st year and 2nd year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length change | Axial length (mm) will be measured after cycloplegia using a non-contact optical biometer. Change in axial length from the baseline over a first 12-month period and a 12-month period of follow-up will be measured | Baseline, 1st year and 2nd year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myopia, Defocus