Influence of ranibizumab, laser photocoagulation or combination therapy on high-risk proliferative diabetic retinopathy

Abstract

Purpose : To investigate the effect of ranibizumab, panretinal laser photocoagulation (PRP) or combination therapy on high-risk proliferative diabetic retinopathy (PDR) in the PRIDE study.

Methods : The PRIDE study (NCT01594281) is a 12-month, Phase II, multicenter, open-label but central reading center-blinded, randomized, controlled study with an observational follow-up until Month 24. Following 1:1:1 randomization to the three treatment arms, 106 patients with PDR without foveal macular edema were treated for 12 months as needed. The severity of diabetic retinopathy was determined using the ETDRS severity scale. However, fluorescein angiography was used in addition to color fundus photography for the identification of neovascularization. Prior PRP treatment was not considered for determining the severity level. Outcomes are reported for the subset of PRIDE study patients with high-risk PDR at baseline.

Results : In the first year, patients in the ranibizumab group (n=35) received a mean ± SD of 5.2 ± 2.3 injections, patients in the PRP group (n=35) 1,919 ± 673 laser spots and patients in the combination group (n=36) 5.0 ± 2.2 injections and 1,670 ± 568 PRP laser spots. At baseline, 28 of the 106 patients (26.4%) showed high-risk PDR. The ranibizumab group included 9 patients with high-risk PDR at baseline, at Month 3 (12), 2 (1) of these patients were graded with NPDR, 3 (1) with mild PDR, 1 (2) with moderate PDR, 2 (4) with high-risk PDR and none of the patients developed advanced PDR. In the PRP group, 10 patients had high-risk PDR at baseline, which at Month 3 (12) shifted to 0 (1) patients with NPDR and mild PDR, respectively, 3 (2) with moderate PDR, 6 (3) with high-risk PDR and 1 (0) with advanced PDR. In the combination group, 9 patients were graded with high-risk PDR at baseline. At Month 3 (12), 3 (2) of these patients were diagnosed with NPDR, 1 (2) with mild PDR, 1 (3) with moderate PDR, 3 (0) with high-risk PDR and none of the patients with advanced PDR.

Conclusions : Ranibizumab has a positive effect on high-risk PDR, leading to frequent lowering of severity levels compared to baseline. However, to maintain this initial effect seen after the loading dose of three injections, continuous treatment might be advisable. Alternatively, a combination of ranibizumab (for a quick response) and PRP (for maintenance) may be an individualized option for patients with high-risk PDR.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.