Highly Aspherical Lenslet (HAL) and Binocular Vision (BV) Disorders [HALT X(T) Study] (HALT XT)

Assess the effect and changes of eye misalignment (strabismus) with myopia control glasses Assess the efficacy of myopia control glasses on childhood myopia progression in children with strabismus due to the uncertainty clinicians face when prescribing myopia control glasses to these strabismic children

Study Overview

• Status: Not yet recruiting
• Conditions: Strabismus; Myopia
• Intervention / Treatment: Device: HAL lenses for children with strabismus; Device: SVL for children with strabismus

Detailed Description

Studies have been done to show that spectacles, atropine eye drops, and outdoor activities have some efficacy in slowing myopia progression in children, however most of such studies exclude children with significant eye conditions such as strabismus or nystagmus to isolate the effects of myopia control treatment. In this study, we would like to investigate whether these specialized glasses can effectively slow down the progression of myopia in children with strabismus. Since strabismus can affect visual development, this study would also be able to assess the effect and changes of eye misalignment (strabismus) with myopia control glasses. The study also aims to assess the efficacy of myopia control glasses on childhood myopia progression in children with strabismus due to the uncertainty clinicians face when prescribing myopia control glasses to these strabismic children.

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Bryan Sim BSX Sim, MD FRCOphth (UK); Phone Number: 62277255 +6562277255; Email: bryansimxr@hotmail.com

Study Locations

• Singapore
  • Singapore, Singapore
    • Singapore National Eye Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Age 5-12 years old Myopia of between -1D and -6D in at least 1 eye Progression of at least 0.5D within the last year Astigmatism less than 2.5D Exotropia Exophoria: horizontal deviation <40PD Esotropia (good control), Esophoria: horizontal deviation <40PD Any vertical strabismus: Vertical deviation <10 PD Intermittent exotropia (good, moderate, poor) Horizontal deviation ≥15 PD, vertical deviation ≤5 PD (?)

Exclusion Criteria:

VA poorer than logMAR 0.2 (6/9.5) in either eye Any other ocular condition (e.g. lens opacity, glaucoma) other than myopia, strabismus or nystagmus) Any medical/neurological condition which would interfere with subjects ability to co-operate with tests and attend follow-up appointments.

Plans of surgery for strabismus or nystagmus in the next year Constant XT). Past use of any other from of myopia control treatment (eg. atropine or myopia control glasses or contact lenses) within the last year.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: HALT lenses for children with strabismus; Stellest lenses for children with strabismus	Device: HAL lenses for children with strabismus; It has been shown that peripheral segmented defocus spectacles can slow myopia progression. The Essilor® Stellest™ lens has been designed with an exclusive and pioneering technology called HALT (Highly Aspherical Lenslet Target). The HALT technology is made of a constellation of 1,021 invisible lenslets. This constellation creates a signal in front of the retina that acts as a shield against eye elongation and, therefore, myopia progression. Studies suggest that children are tolerable against these glasses, and the lenses can slow down myopia progression by 67% on average, compared to single vision lenses, when worn 12 hours a day. It can be considered as one of the best available myopia control spectacle lens designs, being superior to progressive addition and bifocal lenses.
Placebo Comparator: SVL for children with strabismus	Device: SVL for children with strabismus; SVL for children with strabismus; Other Names: Single Vision Lenses

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To assess the efficacy of HAL lenses in childhood myopia control in children with strabismus and nystagmus	a. Efficacy in each eye - i. Primary outcome: change in AL in first vs second 6m ii. Secondary outcome: change in cycloplegic SE & OCT choroidal thickness b. Alternative analysis: Difference between preferred/non-preferred eye, better-worse squint (size and control at baseline and 6m).	2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To assess the effect on strabismus (subjectively and functionally) over first vs second 6m	Primary measure: Change in squint size and control as measured by Newcastle control score (NCS)	2 years

Collaborators and Investigators

• Sponsor: Singapore National Eye Centre

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2025
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2030

Study Registration Dates

• First Submitted: March 3, 2025
• First Submitted That Met QC Criteria: March 3, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 3, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: Strabismus; Myopia; HALT; Myopia Control; Stellest
• Additional Relevant MeSH Terms: Nervous System Diseases; Eye Diseases; Refractive Errors; Cranial Nerve Diseases; Ocular Motility Disorders; Myopia; Strabismus
• Other Study ID Numbers: SingaporeNEC_HALTXT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Inclusion exclusion criteria Age Myopia progression Axial length
• IPD Sharing Time Frame: June 2025 to June 2028
• IPD Sharing Access Criteria: PI Co-PI Study members
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No