Suprachoroidal injection of triamcinolone acetonide plus intravitreal bevacizumab in diabetic macular edema: a randomized pilot trial

BACKGROUND: To investigate the efficacy of injecting suprachoroidal triamcinolone acetonide (SCTA) plus intravitreal bevacizumab (IVB) into patients with center-involving diabetic macular edema (CI-DME). METHODS: In this phase 2/3 randomized controlled pilot trial, sixty-six eyes with CI-DME and best-corrected visual acuity (BCVA) of at most 20/50 Snellen chart were randomly assigned into two groups. Monotherapy arm received sham injection plus 3 monthly IVB doses and combination arm received a single dose of SCTA and 3 monthly IVB doses. The mean improvements in BCVA and Central subfield thickness (CST), over the three-month was considered the main efficacy outcomes. RESULTS: The mean BCVA improvements were obtained respectively as − 0.20 ± 0.20 log [minimum angle of resolution (MAR)] (P = 0.004) and 0.37 ± 0.24 log MAR (P < 0.001) in monotherapy and combination arms [between-group analysis (P = 0.014)]. Significant improvements were also observed in CST (P = 0.019) in the combination arm compared to the other. No adverse events (elevated intraocular pressure, cataract) were observed in any of the study arms. CONCLUSION: Significant improvements in BCVA and retinal anatomical outcomes demonstrated the additive effects of SCTA to those of anti-vascular endothelial growth factors with no short-term side effects and this combination appears to be a promising option in the management of patients with CI-DME. TRIAL REGISTRATION: The trial was registered in Iranian Registry of Clinical Trials (IRCT20200314046761N1).