Time Course of Retinopathy of Prematurity Regression and Reactivation After Treatment with Ranibizumab or Laser in the RAINBOW Trial.

ABSTRACT

PURPOSE: To study the time course of retinopathy of prematurity (ROP) regression and reactivation after treatment with intravitreal ranibizumab or laser in the ranibizumab compared with laser therapy for the treatment of infants born prematurely with ROP trial. DESIGN: Post hoc analysis of a randomized, clinical trial. SUBJECTS: A total of 225 infants (448 eyes) were randomized to ranibizumab 0.2 mg (n = 74, 148 eyes), ranibizumab 0.1 mg (n = 77, 152 eyes), and laser (n = 74, 148 eyes). METHODS: Features of disease regression were measured using time-to-event analysis per eye, corrected for within-subject association. Analyses of disease reactivation and additional treatments were descriptive. MAIN OUTCOME MEASURES: Median time to regression of plus disease, stage 3 ROP, aggressive posterior (AP)-ROP to 24-week follow-up and disease reactivation and first additional treatment to 2-year follow-up. RESULTS: The median times to regression after ranibizumab 0.2 mg vs. laser were as follows plus disease, 4 vs. 16 days (P < 0.001); stage 3 ROP, 8 vs. 16 days (P = 0.004); and AP-ROP, 7.3 vs. 22 days (P = 0.03). Results for ranibizumab 0.1 mg were similar to those for 0.2 mg, with a median of 4, 9, and 8 days, respectively. Additional treatments were given in 34 (25%) of 138 eyes after laser and 40 (27%) of 146 and 42 (28%) of 152 eyes after 0.2 mg and 0.1 mg ranibizumab, respectively. Incomplete disease regression requiring additional treatment occurred in 30 (22%) of 138 eyes after laser after a median interval of 15 days compared with 11 (8%) of 146 and 9 (6%) of 152 after 0.2 mg and 0.1 mg ranibizumab after a median interval of 21 and 13 days, respectively. Retinopathy of prematurity reactivation requiring additional treatment occurred in 3 (2%) of 138 eyes after laser after a median interval of 43 days compared with 22 (15%) of 146 and 26 (17%) of 152 after 0.2 and 0.1 mg ranibizumab after a median interval of 53.5 (maximum, 105) and 54.5 days (maximum, 128), respectively. CONCLUSIONS: Intravitreal 0.2 or 0.1 mg ranibizumab induced a faster regression of plus disease, stage 3 ROP, and AP-ROP than laser did. Ranibizumab was associated with fewer additional treatments for incomplete disease regression but more for disease reactivation.