Short-term reactivation of retinopathy of prematurity following primary ranibizumab treatment.

PURPOSE: Investigate risk factors for short term reactivation of retinopathy of prematurity (ROP) after intravitreal ranibizumab (IVR) therapy and determine safety and efficacy of repeat injections.

METHODS: Retrospective chart review study of patients screened for ROP as inpatients between 2013-2023 who received IVR within the UCLA healthcare system. Primary outcomes were rates and timing of short term ROP reactivation, defined as repeat worsening of ROP to stage 2 or 3 before 52 weeks postmenstrual age (PMA), as well as risk factors for reactivation. Other outcomes included adverse events and rates of reactivation after a second intravitreal injection.

RESULTS: 82 eyes of 43 patients received primary IVR 0.25mg/0.025cc for type 1 ROP. 13 patients (22 eyes) (30.2% of patients, 26.8% of eyes) developed short term reactivation an average of 7.2±1.7 weeks after treatment. Increased reactivation risk was associated with zone I disease (OR 6.23, 95% CI 1.35-28.7, p=0.019), lower PMA at 1st injection (OR 1.64, 95% CI 1.19-2.26; p=0.003), and lower gestational age at birth (OR 1.80, 95% CI 1.04-3.13, p=0.037). Of the 13 patients that received repeat injections, 5 required laser treatment for a second reactivation (11.6% of patients receiving IVR). No eyes developed retinal vascular occlusion, endophthalmitis or cataract.

CONCLUSION: Repeat injections may be required after primary IVR for aggressive ROP. Repeat IVR treatment for ROP is effective and poses few ophthalmic adverse events, though additional reactivation remains a risk.