Predictors of Diabetic Macular Edema Treatment Frequency with Ranibizumab During the Open-Label Extension of the RIDE and RISE Trials

PurposeTo investigate the role of baseline demographics, disease characteristics, and treatment responses to ranibizumab during RIDE/RISE in predicting long-term treatment frequency with a criteria-based pro re nata (PRN) regimen during the open-label extension (OLE).DesignPooled, retrospective, post hoc analysis from the phase III, randomized RIDE/RISE studies and subsequent OLE.ParticipantsFive hundred patients enrolled in the OLE after completion of the 36-month RIDE/RISE studies.MethodsSummary statistics of RIDE/RISE baseline characteristics and treatment responses were generated by PRN ranibizumab 0.5 mg annualized injection frequency in the OLE (0 and >7 annualized injections). Univariable regression and analysis of variance, and multivariable analysis of covariance were performed on the annualized number of ranibizumab injections administered during the OLE versus baseline characteristics and response to treatment during the RIDE/RISE studies.Main Outcome MeasuresAssociation of patient characteristics and responses to treatment during RIDE/RISE with the observed ranibizumab treatment burden during the OLE.ResultsDuring the OLE, 121 patients required no treatment, 132 required >0 to ≤3 annualized injections, 159 required >3 to ≤7 annualized injections, and 88 required >7 annualized injections. Parameters identified in the multivariable analysis as related to the annualized number of injections included the total number of rescue focal macular lasers received during the core studies (P = 0.0203), central foveal thickness at baseline (P = 0.0002) and month 36 (P < 0.0001), fluorescein leakage area at month 36 (P = 0.0137), and glycated hemoglobin (HbA1c) levels at month 36 (P = 0.0054). Patients receiving 0 versus >7 annualized injections during the OLE had, on average, a shorter duration of diabetes and diabetic macular edema (DME) at baseline, were less likely to have proliferative diabetic retinopathy at baseline, received fewer rescue focal macular laser treatments, and were more likely to experience diabetic retinopathy severity scale improvement of ≥2 steps.ConclusionsPatients who received less frequent injections during the RIDE/RISE OLE tended to have less advanced disease at baseline and responded better to initial ranibizumab treatment, suggesting that earlier anti-vascular endothelial growth factor treatment of center-involving DME with visual acuity loss may decrease long-term treatment burden.