Comparison between intravitreal bevacizumab and posterior sub-tenon injection of triamcinolone acetonide in macular edema secondary to retinal vein occlusion

Novel pharmaceuticals for the management of retinal vein occlusion and linked disorders

INTRODUCTION

Retinal vein occlusion (RVO) is the second leading cause of blindness from retinal vascular disease behind diabetic retinopathy. Anti-vascular endothelial growth factor (VEGF) and glucocorticoid therapy are the cornerstones of pharmaceutical treatment for RVO. There is considerable interest in developing new pharmaceuticals in and out of these two classes to reduce costs, lower injection burden, and treat the occlusion itself, rather than the complications.

AREAS COVERED

In this review, we discuss novel pharmaceuticals for the treatment of RVO outside of current standard of care. We performed a comprehensive literature search encompassing pharmaceuticals that have recently been approved or have shown promising results in early clinical trials or animal models.

EXPERT OPINION

Anti-VEGF therapy remains the most efficacious treatment for RVO with a very favorable side effect profile. New biosimilars reduce costs while maintaining efficacy. Novel glucocorticoids may be a useful therapy in patients for whom anti-VEGF therapy has failed, or as an adjunct. Pharmaceuticals in other drug classes, particularly those with neuroprotective or regenerative properties, as well as those geared toward treating the occlusion itself, represent exciting options for early RVO therapy, but are likely years away from clinical relevance.

Analysis of intravitreal bevacizumab treatment for macular oedema due to retinal vein occlusion

PURPOSE

Our aim was to analyse the clinical effect of intravitreal bevacizumab treatment for macular oedema due to central/branch retinal vein occlusion (CRVO/BRVO). The end points were final best-corrected visual acuity (BCVA), BCVA improvement, final central 1-mm macular subfield thickness (CST) and change in CST.

METHODS

Our study included 34 CRVO and 25 BRVO patients. Patients received intravitreal bevacizumab (IVB) treatment at our department. Our control group consisted of 50 CRVO and 30 BRVO patients, who had not received this treatment because their disease developed before the anti-VEGF treatment became available. For statistical analysis, two-sample t-test, Pearson's correlation, and ANOVA were used. The level of significance was defined at p < 0.05.

RESULTS

With the two-sample t-test we found significant improvement of BCVA in the IVB-treated group (CRVO: 0.171 ± 0.270, p1 = 3.25×10-4; BRVO: 0.215 ± 0.282, p2 = 5.52×10-4). The difference in BCVA improvement was also significant compared to the control group (CRVO: p1 = 3.46×10-4; BRVO: p2 = 0.003). Significant decrease was observed in the CST in the treated group (CRVO: -345.114 ± 280.577, p1 = 6.94×10-9; BRVO: -151.875 ± 174.341, p2 = 1.67×10-4). In case of BRVO patients the final BCVA was significantly better in the treated group (0.617 ± 0.334) compared to the control group (0.406 ± 0.357), p = 0.016.

CONCLUSION

IVB treatment results in significantly better final visual acuity and leads to significantly increased BCVA improvement compared to patients with RVO-induced macular oedema receiving no treatment.

The effects of intravitreal injections on intraocular pressure and retinal nerve fiber layer: a systematic review and meta-analysis

The number of eye diseases treated with intravitreal injections is increasing. Obviously, an injection of fluid into the eye results in an increase of intraocular pressure (IOP), the main risk factor for glaucoma. However, the effect of these repeated IOP increases on the eye is unclear. Therefore, we performed a systematic review with meta-analyses. PubMed, Embase and Clinical Trials Registries were searched for articles investigating the relationship between intravitreal injections (anti-vascular endothelial growth factor [anti-VEGF] or steroids) and either IOP, retinal nerve fiber layer (RNFL)-thickness and glaucoma. Multiple meta-analyses were performed, combining data on intravitreal injection of anti-VEGF medication and dexamethasone implants. A total of 74 articles were eligible for meta-analyses. The short-term effect of an intravitreal injection of anti-VEGF showed a statistically significant increase in IOP. One day after injection of anti-VEGF, however, IOP was significantly lower than baseline. The long-term time-intervals showed no significant difference in IOP. After intravitreal injection of a dexamethasone implant, IOP was significantly higher than baseline 1 month post-injection. RNFL-thickness was significantly reduced 6 and 12 months post-injection of anti-VEGF, as well as at end of follow up. Caution is advised when using intravitreal medication, especially when treating patients with advanced glaucoma; in these cases, prophylactic IOP-lowering medication may be considered.