Myopia Control Using Novel Soft Contact Lenses

This is a double-masked and randomized controlled trial. Participants will be randomly assigned to one of three interventions: two study contact lenses (CL)(Lens A or Lens B) or single vision (SVCL) for the initial 12 months. While the Lens A/B groups will continue their respective lenses, the participants initially assigned to the SVCL will cross over to Lens A at the 12-month mark. All participants will then continue lens wear for an additional 12 months. Their cycloplegic refraction and axial length will be monitored every 6 months for 2 years.

Inclusion criteria

• • Age at enrolment: 7 - 12 (both inclusive) years old Hong Kong Chinese schoolchildren

• Refractive errors in terms of spherical equivalent refraction (SER) determined by cycloplegic autorefraction: -0.75 diopters (D) to -5.00D in both eyes
• Astigmatism: equal or less than -1.00D
• Anisometropia: equal or less than -1.75D
• Previous myopia progression:

• -0.50D (in SER) per year or more in 1 eye or both eyes OR Axial length elongation: 0.27mm/year in 1 eye or both eyes
• If myopia is initially detected during screening, eligibility requires an SER below the 3rd percentile curve of refraction in either or both eyes (4)
• Best corrected visual acuity: better than 0.04 LogMAR in both eyes
• Ocular health: no abnormalities in both internal and external ocular health
• Systemic health: no systemic interference with ocular vision functioning
• Binocular vision: no strabismus and other binocular abnormalities
• No medication or supplements that affect eye growth
• Normal colour vision
• No previous use of myopic control interventions such as red-light therapy, atropine, orthokeratology, specialized spectacle lenses and contact lenses and oral supplements for myopic control
• Agree to maintain the visit schedule and be able to keep all appointments as specified in the informed assent and consent forms throughout study duration.
• Agree to accept either the control or study lens as assigned by the randomization scheme
• Agree to wear the assigned contact lenses for a minimum of 10 hours per day, at least 6 days per week, for the duration of the 2-year study and to inform the study investigator if this schedule is interrupted. Wearing time may be modified by the study staff for health reasons
• Agree to adhere to contact lens use requirements throughout study duration
• Acceptance of the masked study design

Exclusion criteria

• Contraindications for soft contact lenses
• Dry eye with drug intervention within 30 days

• Regular use of ocular medication (prescription or over-the-counter), artificial tears, or wetting agents due to dryness, allergies or other conditions that hinder the contact lens wear
• Current use of systemic medications that may significantly affect contact lens wear, tear film production, pupil size, accommodation, or refractive state. These include, but not limited to, long term use of nasal decongestants (e.g., pseudoephedrine, phenylephrine), antihistamines (e.g., chlorpheniramine, diphenhydramine, Prednisolone or Ritalin (methylphenidate)
• Pre-existing systemic and ocular disease that had an influence on contact lens wearing
• History of ocular injury or surgery
• Prior use of myopic control interventions such as red-light therapy, atropine, orthokeratology, specialized spectacle lenses and contact lenses and oral supplements
• Allergy to cyclopentolate eye drops
• Subjects who, in the judgment of the Investigator, are unable to cooperate and follow instructions during eye examination