Abstract
Purpose :
Patients with diabetic macular edema are commonly treated with intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents. However, a substantial amount of patients show a suboptimal response to this treatment. It is therefore important to identify poor responders to assure they can benefit from alternative therapies. The aim of this study was to investigate whether circulating microRNA (miRNA) levels could serve as a predictive biomarker for the responsiveness to anti-VEGF therapy in patients with diabetic macular edema.
Methods :
Whole blood samples were collected from 135 patients who were included in the BRDME study, a randomized controlled trial comparing bevacizumab to ranibizumab in the treatment of patients with diabetic macular edema (Trialregister.nl, NTR3247). Participants received monthly injections of 1.25 mg bevacizumab or 0.5 mg ranibizumab for a time period of 6 months. Visual acuity and central area thickness were measured monthly during follow-up. Blood samples for RNA extraction were collected during screening visit, before administration of the first injection. Circulating levels of selected miRNAs were quantified, which included miRNA-7, miRNA-21, miRNA-133b, miRNA-181a, miRNA-222, miRNA-181c and miRNA-1197.
Results :
After linear regression analysis, levels of miRNA-133b correlated with visual acuity at baseline (P < 0.001), and were positively associated with the change in visual acuity between baseline and 3 months of treatment (P < 0.001) and between baseline and 6 months of treatment (P < 0.001). In contrast, levels of miRNA-7 were negatively associated with visual acuity outcomes after 6 months only (P = 0. 018). No association was found between circulating miRNA levels and change in central area thickness.
Conclusions :
This study shows that miRNA-133b is positively associated with both baseline visual acuity and with the change in visual acuity from baseline to 3 and 6 months in patients with diabetic macular edema treated with anti-VEGF agents. For miRNA-7, higher concentrations are associated with worse visual outcomes. Our findings suggest that circulating miRNA-133b and miRNA-7 may be positive and negative predictive biomarkers for better visual acuity outcome after anti-VEGF therapy, respectively.
This is a 2020 ARVO Annual Meeting abstract.