Overview

This is a prospective, randomized, parallel-group, assessor-masked, non-inferiority clinical trial designed to compare the efficacy, safety, and adherence of AmblyoFix binocular digital therapy with standard occlusion (patching) for the treatment of unilateral amblyopia in children and young adults aged 8 to 35 years. In the event that adequate recruitment within this age range is not feasible, the age range may be modified, subject to appropriate ethical approval and protocol amendment procedures.

A total of 86 participants will be enrolled (43 per arm). Eligible participants will be randomized in a 1:1 ratio to receive either AmblyoFix or patching, stratified by age group and amblyopia severity. Randomization will be implemented using the sealed opaque envelope method, with allocation concealment maintained through sequentially numbered, tamper-proof envelopes.

The primary outcome is the change in amblyopic-eye best-corrected visual acuity (BCVA, logMAR) from baseline to 24 weeks, assessed under standardized Snellen or ETDRS protocol. Secondary outcomes include adherence, safety, and patient-reported outcomes. An interim analysis will be performed at 12 weeks, with the option to stop the trial early if sufficient improvement in BCVA is demonstrated.

Participants and caregivers cannot be blinded due to the nature of the interventions; however, outcome assessors and statisticians will remain blinded to treatment allocation to minimize bias. Follow-up assessments will occur at baseline, 4, 8, 12, 16, 20 and 24 weeks, with no additional amblyopia treatment permitted during the study unless clinically required.

This trial aims to rigorously determine whether AmblyoFix is a safe, effective, and non-inferior alternative to standard patching, with the potential to improve adherence and acceptability in amblyopia therapy.

Eligibility

Inclusion Criteria:

• Age 8-35 years.
• Unilateral amblyopia secondary to anisometropia, strabismus, or mixed.
• BCVA in amblyopic eye between 20/40-20/400 (0.3-1.3 logMAR); fellow eye ≥20/32 (≤0.2 logMAR).
• Interocular difference ≥2 lines (≥0.2 logMAR).
• Stable refractive correction for ≥16 weeks or \<0.1 logMAR change across two visits ≥8 weeks apart.
• Cycloplegic refraction within 7 months meeting anisometropia criteria (e.g., hyperopia ≥+2.50 D).
• Access to a suitable home environment (laptop and internet) for AmblyoFix arm.
• Parent/guardian consent and child assent (8+ year olds).

Exclusion Criteria:

• Atropine use within 2 weeks before starting treatment
• Prior amblyopia treatment beyond refractive adaptation.
• Myopia \>-6.00 D SE, previous ocular surgery, or other ocular pathology.
• Severe cognitive/developmental delay impeding compliance.
• History of light-induced seizures.
• Inability/unwillingness to comply with digital monitoring.
• Any condition compromising safety or trial integrity.