Switching to ziv-aflibercept in resistant diabetic macular edema non responsive to ranibizumab injection

Background Diabetic macular edema (DME) is a leading cause of visual loss in diabetic patients and is managed using multiple anti-vascular endothelial growth factor (VEGF) agents such as bevacizumab, ranibizumab and aflibercept. The present study evaluates effectiveness of intravitreal injection of ziv-aflibercept in resistant diabetic macular edema. Methods This is a prospective interventional study that was carried out on 59 eyes of 40 diabetic patients with diabetic macular edema resistant to three prior consecutive ranibizumab injections. On all patients, thorough ophthalmic evaluation including optical coherence tomography was performed. In patients with persistent intraretinal or subretinal fluid, ziv- aflibercept 1.25 mg (0.05 ml) was administered by intravitreal injection monthly during the 6 month study period from June to December 2019. Results The central macular thickness (CMT) decreased significantly from 395.08 +/- 129.9 um at baseline to 282.39 +/- 95.278, 245.36 +/- 79.861 and 201.17 +/- 54.042 after 1, 3 and 6 months of treatment respectively (p < 0.001). Best corrected visual acuity (BCVA) in log MAR units was significantly improved from 0.95 +/- 0.21 to 0.51 +/- 0.23 after 6 months (p = 0.001). After treatment, negative correlations were detected between age, number of injections, duration of DM and level of glycated hemoglobin (HbA1c) and variation of both CMT and BCVA. The only significant predictor for low final CMT after 6 months of injection was the CMT after 3 months of injection (p = 0.001). Conclusion Ziv-aflibercept is a highly effective and safe drug in cases of DME resistant to previous ranibizumab injections especially in low-income countries.