A 12-month prospective study to evaluate the efficacy of using the treat-and-extend regimen with intravitreal aflibercept as a Second-Line Treatment for Diabetic Macular Oedema (the TADI Study)

Purpose: To evaluate the efficacy of intravitreal aflibercept as a second-line therapy in eyes with persistent diabetic macular oedema (DMO) despite receiving initial bevacizumab treatment. Methods: A prospective multicentre study was conducted in nine academic clinics in Israel. Starting from the first follow-up visit, a treat-and-extend regimen was applied in which the treatment intervals were extended by 2 weeks based on macular thickness using SD-OCT. The primary outcome was central subfield thickness (CST) at week 52. Results: Forty-four patients (n = 48 eyes) were recruited to the study, and 43 eyes completed 52 weeks of follow-up. Patients received a mean (±SD) of 7.9 ± 3.5 bevacizumab injections before enrolment. The mean (±SD) CST under aflibercept therapy decreased from 468 ± 131 μm at baseline to 303 ± 67 μm at 52 weeks (p = 0.002), and best corrected visual acuity improved from 64 ± 15 ETDRS letters at baseline to 75 ± 8 letters at week 52 (p = 0.001). Twenty (46%) eyes met the treat-and-extend criteria and received a mean (±SD) of 10.9 ± 2 aflibercept injections. Conclusions: Eyes with persistent DMO following initial bevacizumab therapy had a marked reduction in macular thickness and improved visual acuity following 1 year of treatment with intravitreal aflibercept. Less than half of the patients met eligibility criteria for extension of the treatment interval; for these patients, the treat-and-extend regimen resulted in a maximum treatment interval of 10 weeks during the first year.