Comparison of intravitreal dexamethasone implant and anti-VEGF drugs in the treatment of retinal vein occlusion-induced oedema: a meta-analysis and systematic review

OBJECTIVE: To compare the efficacy and safety of intravitreal dexamethasone (DEX) implant and anti-vascular endothelial growth factor (anti-VEGF) agents in the treatment of macular oedema secondary to retinal vein occlusion (RVO). DESIGN: Systematic review and meta-analysis based on Grading of Recommendations Assessment, Development and Evaluation (GRADE). DATA SOURCES: PubMed, Cochrane Library and ClinicalTrials.gov registry were searched from inception to 10 December 2019, without language restrictions. ELIGIBILITY CRITERIA: Randomised controlled trials (RCTs) and real-world observation studies comparing the efficacy of DEX implant and anti-VEGF agents for the treatment of patients with RVO, naïve or almost naïve to both arms, were included. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently extracted data for mean changes in best-corrected visual acuity (BCVA), central subfield thickness (CST) and product safety. Review Manager V.5.3 and GRADE were used to synthesise the data and validate the evidence, respectively. RESULTS: Four RCTs and 12 real-world studies were included. An average lower letter gain in BCVA was determined for the DEX implant (mean difference (MD) = −6.59; 95% CI −8.87 to −4.22 letters) administered at a retreatment interval of 5–6 months. Results were similar (MD(6 months)=−12.68; 95% CI −21.98 to −3.37 letters; MD(12 months)=−9.69; 95% CI −12.01 to −7.37 letters) at 6 and 12 months. The DEX implant resulted in comparable or marginally less CST reduction at months 6 and 12 but introduced relatively higher risks of elevated intraocular pressure (RR=3.89; 95% CI 2.16 to 7.03) and cataract induction (RR=5.22; 95% CI 1.67 to 16.29). Most real-life studies reported an insignificant numerical gain in letters for anti-VEGF drugs relative to that for DEX implant. However, the latter achieved comparable efficacy with a 4-month dosage interval. CONCLUSION: Compared with anti-VEGF agents, DEX implant required fewer injections but had inferior functional efficacy and safety. Real-life trials supplemented the efficacy data for DEX implant.