Randomized Trial Comparing Immediate vs. Deferred Surgery for Symptomatic ERM

Key Inclusion Criteria:

• Age ≥ 45 years

• E-ETDRS visual acuity 20/40 or better (≥69 letters) o ERM must be thought to be the primary cause of vision loss

• ERM meeting the following criteria, according to the investigator

• ERM is not secondary to another condition

• Symptoms of visual loss and/or distortion (in the opinion of the investigator,the ERM is contributing to the participant's symptoms); either new or worseningin the past 24 months

• Epiretinal membrane involving or altering the central 3 mm of the macula on OCT

• Distortion within the central subfield due to ERM on OCT

• Immediate vitrectomy not required (investigator and participant are willing to waitat least 4 weeks to see if vision remains stable without having to proceed tovitrectomy)

• No known medical problems that will be a contraindication to surgery

Key Exclusion Criteria:

• History of retinal vascular disease

• History of vitreous hemorrhage if vitreous hemorrhage is thought to have caused theERM o History of vitreous hemorrhage is permitted provided the vitreous hemorrhage didnot cause the ERM in the investigator's opinion

• History of inflammatory disease unless mild and completely resolved at least oneyear prior to randomization

• History of diabetic macular edema (DME), retinal vein occlusion (RVO), or uveitis (except mild uveitis that resolved >1 year prior to randomization)

• Prior intraocular surgery (except uncomplicated cataract extraction)

• Cataract extraction within prior 3 months

• Laser or cryosurgical retinopexy within one month of randomization

• Pneumatic retinopexy within one year of randomization

• Current untreated retinal tear or detachment o A previously treated retinal tear with up to one disc diameter radius ofsubretinal fluid is permitted

• Macular hole

• Degenerative lamellar macular hole o ERM foveoschisis ("tractional" lamellar hole) is permitted

• Vitreomacular traction within 1,500 microns of foveal center

• Central serous chorioretinopathy

• Nonproliferative diabetic retinopathy or worse (DR severity >20)