Table 1.

Eligibility and Exclusion Criteria

Eligibility Criteria Age 3 to < 10 years Amblyopia associated with strabismus (comitant or incomitant), anisometropia, or both, meeting the following criteria: ◆ Strabismic amblyopia: At least one of the following criteria must be met and criteria are not met for combined-mechanism amblyopia: ➢ Heterotropia at distance and/or near fixation on examination (with or without spectacles) ➢ History of strabismus surgery (or botulinum) ➢ Documented history of strabismus which is no longer present (and which, in the judgment of the investigator, is the cause of amblyopia) ◆ Anisometropic amblyopia: At least one of the following criteria must be met: ➢ ≥0.50 D difference between eyes in spherical equivalent ➢ ≥1.50 D difference between eyes in astigmatism in any meridian ◆ Combined mechanism amblyopia: Both of the following criteria must be met: ➢ Criteria for strabismus are met (see above) ➢ ≥1.00 D difference between eyes in spherical equivalent or ≥1.50 D difference between eyes in astigmatism in any meridian Visual acuity, measured using the ATS single-surround HOTV protocol for subjects aged < 7 years and the E-ETDRS visual acuity testing protocol for subjects 7 to < 10 years using the Electronic Visual Acuity Tester, meeting the following criteria: ◆ Best corrected visual acuity in the amblyopic eye 20/40 to 20/80 inclusive (71 to 54 letters inclusive) ◆ Best corrected visual acuity in the fellow eye ≥ 20/40 (≥ 69 letters) ◆ Inter-eye acuity difference ≥ 3 logMAR lines (i.e., amblyopic eye acuity at least 3 lines by ATS-HOTV or at least 15 letters by E-ETDRS worse than the fellow eye acuity) No amblyopia treatment other than spectacles used in the past six months prior to enrollment. Any treatment more than 6 months prior to enrollment is acceptable Ocular examination within 6 months prior to enrollment Cycloplegic refraction within 6 months prior to enrollment Spectacles must be worn currently. Spectacle correction for measurement of enrollment visual acuity must meet the following criteria and be based on a cycloplegic refraction that is no more than 6 months old. ◆ Requirements for spectacle correction ➢ Spherical equivalent must be within 0.50 D of fully correcting the anisometropia ➢ Hypermetropia must not be undercorrected by more than +1.50 D spherical equivalent, and reduction in plus must be symmetric in the two eyes ➢ Cylinder power in both eyes must be within 0.50 D of fully correcting the astigmatism ➢ Cylinder axis in the spectacle lenses in both eyes must be within 6 degrees of the axis of the cycloplegic refraction when cylinder power is ≥ 1.00 D ➢ Myopia of the amblyopic eye greater than 0.50 D by spherical equivalent ➢ must be corrected, and the glasses must not undercorrect the myopia by more than 0.25 D or overcorrect it by more than 0.50 D ◆ Spectacles meeting above criteria must be worn either: ➢ for 16 weeks immediately prior to enrollment, or ➢ until visual acuity in amblyopic eye is stable (defined as two consecutive visual acuity measurements by the same testing method at least 4 weeks apart with no improvement of one logMAR line or more) ▪ An acuity measurement done any of the following ways may be considered the first of two consecutive measurements: 1) in current glasses, 2) in trial frames with full correction of hypermetropia with cycloplegia, or 3) by having the subject return in new glasses for first measurement. Note: since this determination is a pre-study procedure, the method of measuring visual acuity is not mandated.

Exclusion Criteria Presence of an ocular cause for reduced vision Myopia > −6.00 D spherical equivalent in either eye Prior intraocular or refractive surgery Known skin allergy to patch or bandage adhesives Current vision therapy or orthoptics

D = diopters; ATS = Amblyopia Treatment Study; E-ETDRS = Electronic Early Treatment of Diabetic Retinopathy; logMAR = logarithm of the minimum angle of resolution.