Vitrectomy for macular edema due 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.

Acetazolamide and bevacizumab combination therapy versus bevacizumab monotherapy in macular edema secondary to retinal vein occlusion

PURPOSE

To determine and compare the efficacy of intravitreal bevacizumab (IVB) and oral acetazolamide (OA) combination therapy versus IVB monotherapy in patients with macular edema secondary to retinal vein occlusion (RVO).

METHODS

This randomized clinical trial included 54 eyes of 52 patients with RVO central macular thickness (CMT) of more than 300μm, and best corrected visual acuity (BCVA) between 20/400 and 20/40. Eligible patients were randomly assigned to two groups: (I) IVB and OA (250mg twice daily) combination therapy or (II) IVB monotherapy. Ocular injections were repeated monthly for up to three months; BCVA and CMT were measured monthly.

RESULTS

Both regimens resulted in significant reduction in CMT (534±150μm to 352±90μm in the IVB+OA group, P<0.001; and 580±175μm to 362±90μm in the IVB group, P<0.001); neither showed superiority in this regard. Likewise, BCVA showed significant improvement in both groups (0.87±0.56 to 0.53±0.28 LogMAR in the IVB+OA group, P=0.001; and 0.85±0.62 to 0.46±0.4 LogMAR in the IVB group, P<0.001), with no intergroup difference.

CONCLUSION

Addition of oral acetazolamide to IVB in eyes with macular edema secondary to RVO may not result in additional short-term benefits regarding functional and anatomical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05290948, registered on March 22, 2022. https://clinicaltrials.gov/ct2/show/NCT05290948.

Retinal vein occlusion: drug targets and therapeutic implications

INTRODUCTION

The pathogenesis of retinal vein occlusion (RVO) is extremely complex and includes several mediators. These mediators represent potential drug targets that can be used in the development of intravitreal drugs.

AREAS COVERED

PubMed/MEDLINE databases were accessed between April-May 2021 to find the most relevant scientific papers regarding drug targets and therapeutic implications in RVO, focusing on current therapeutic options and potential cornerstones of future advances in treatment.

EXPERT OPINION

Before the introduction of intravitreal therapies, the visual outcome following a diagnosis of RVO was extremely poor. Anti-VEGF and corticosteroid treatments have radically changed RVO prognosis, helping to preserve patients' visual function and their quality of life. According to current clinical data, anti-VEGF and corticosteroid drugs are associated with both pros and cons; the present recommendation is to employ anti-VEGF molecules as a first-line treatment. Advances in our understanding of the biomolecular characteristics of RVO offer a solid basis for the development of new therapeutic targets and treatments.