Purpose: To study the structural, visual and refractive outcomes of intravitreal injection of aflibercept monotherapy in patients with high-risk prethreshold type 1 retinopathy of prematurity (ROP). Design: Prospective nonrandomized interventional case series study. Patients and Methods: 1 mg/0.025 ml intravitreal aflibercept was administered for patients with high-risk prethreshold type 1 ROP. The primary outcomes studied were unfavorable structural outcome, unfavorable visual outcome and unfavorable refractive outcome. The secondary outcomes were absence of recurrence, ocular and systemic adverse events. Results: Twenty-six eyes were enrolled in the study; all had completed 1 year of follow-up. The mean birth weight was 991 ± 266 g (range: 875-1,105 g); the mean gestational age at birth was 26.33 ± 2.1 weeks (range: 24-30 weeks); 9 eyes were graded as ROP with stage 2+, zone I retinopathy, 14 eyes had stage 3+ disease in zone II and 3 eyes were diagnosed with stage 3 disease in zone I. Twenty-five eyes (96.2%) showed a favorable structural and 21 (80.1%) a favorable visual outcome, and the median refractive error after 1 year was 0.75 dpt (range: -9.5 to +4). Conclusions: Intravitreal injection of aflibercept monotherapy is an easy, safe and effective alternative modality of therapy for high-risk prethreshold type 1 ROP. A further multicenter study with a longer duration of follow-up is required. © 2014 S. Karger AG, Basel