Real-World Results of Switching Treatment from Ranibizumab to Aflibercept in Macular Oedema Secondary to Branch Retinal Vein Occlusion

Branch retinal vein occlusion treated with anti-VEGF: to switch or not to switch?

OBJECTIVE

To evaluate visual outcomes after switching from bevacizumab to ranibizumab or aflibercept in patients with macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

DESIGN

A retrospective, multi-center, observational study.

PARTICIPANTS

Patients diagnosed with BRVO and were treated with at least 3 bevacizumab injections, before anti VEGF switch.

METHODS

The follow-up period was 36 months, and the primary study outcomes assessed changes in best corrected visual acuity (BCVA) after anti VEGF switch.

RESULTS

A total of 263 eyes of 263 patients with a mean age of 71.5 ± 11.2 years of which 50% were of male gender met the inclusion criteria. Of them, 175 eyes did not undergo switch, whereas 88 eyes underwent anti-VEGF switch. There was not a significant difference in mean age (p = 0.634) and gender (p = 0.269) between the groups. Baseline BCVA of the no-switch group was 0.47 ± 0.43 logMAR (20/59 Snellen) versus 0.6 ± 0.49 logMAR (20/79 Snellen) (p = 0.031) in the switch group, and at 36-months it was 0.41 ± 0.39 (20/51 Snellen) logMAR versus 0.54 ± 0.49 logMAR (20/69 Snellen) (p = 0.035), respectively. The difference between the rate of change in BCVA per year was insignificant between groups (p = 0.414). In multivariate analysis, baseline BCVA was the single significant predictor for switch (beta 0.137, p = 0.035). Patients with more than one anti-VEGF switch suffer from decrease in BCVA.

CONCLUSIONS

Worse baseline BCVA is a significant predictor for anti-VEGF switch execution, though the switch has no significant impact on the change in BCVA over time. Multiple anti-VEGF switch is not recommended.

Off-Label Uses of Ranibizumab and Aflibercept for Age-Related Macular Degeneration in Turkey

Purpose

To evaluate the clinical and demographic aspects of off-label drug use applications for age-related macular degeneration (AMD) in Turkey.

Methods

Applications for off-label drug use in the treatment of AMD to the Turkish Medicines and Medical Devices Agency (TITCK) in 2018 were retrospectively analyzed. Demographic characteristics, requested drugs, previous treatment regimens, and reasons for applications were evaluated.

Results

The mean age of the patients (n = 209) was 64.9 ± 15.7 years, of which 48.8% were male and 51.2% were female. Ranibizumab (n = 113) comprised 54.1% and aflibercept (n = 96) 45.9% of off-label use applications. No application was made for bevacizumab. The most frequent reasons for application were switchback (49.3%), nonreimbursement of indicated drugs in cases under 50 years of age (24.4%), and failure to complete the loading dose (14.4%).

Conclusions

Ranibizumab was the most requested off-label drug for AMD. There was no application for off-label bevacizumab since its use does not require approval from TITCK. In Turkey, new rules were established for the reimbursement of intravitreal drugs for AMD in 2019. Three doses of intravitreal bevacizumab were required initially for aflibercept and ranibizumab to be covered for reimbursement. There is not enough data in the English literature regarding the off-label use of ranibizumab and aflibercept for AMD. This study provides information about drug regulations and the off-label treatment options preferred by physicians for AMD in Turkey.

Biological drug therapy for ocular angiogenesis: Anti-VEGF agents and novel strategies based on nanotechnology

Currently, biological drug therapy for ocular angiogenesis treatment is based on the administration of anti‐VEGF agents via intravitreal route. The molecules approved with this purpose for ocular use include pegaptanib, ranibizumab, and aflibercept, whereas bevacizumab is commonly off‐label used in the clinical practice. The schedule dosage involves repeated intravitreal injections of anti‐VEGF agents to achieve and maintain effective concentrations in retina and choroids, which are administrated as solutions form. In this review article, we describe the features of different anti‐VEGF agents, major challenges for their ocular delivery and the nanoparticles in development as delivery system of them. In this way, several polymeric and lipid nanoparticles are explored to load anti‐VEGF agents with the aim of achieving sustained drug release and thus, minimize the number of intravitreal injections required. The main challenges were focused in the loading the molecules that maintain their bioactivity after their release from nanoparticulate system, followed the evaluation of them through studies of formulation stability, pharmacokinetic, and efficacy in in vitro and in vivo models. The analysis was based on the information published in peer‐reviewed published papers relevant to anti‐VEGF treatments and nanoparticles developed as ocular anti‐VEGF delivery system.

Protective effects of hydrogen gas in a rat model of branch retinal vein occlusion via decreasing VEGF-α expression

BACKGROUND

Oxidative stress (OS) is an essential factor in the pathogenesis of branch retinal vein occlusion (BRVO). Studies have demonstrated the role of hydrogen gas in the regulation of OS. This study was designed to evaluate the efficacy of hydrogen gas on the BRVO rat model.

METHODS

Twenty-four BRVO rats were randomly divided into two groups: the hydrogen gas (H) group (42% H2, 21% O2, 37% N2) and the model (M) group (21% O2, 79% N2). Rats in the H group inhaled hydrogen gas for 8 h every day up to 30 d post-occlusion. Twelve age-matched healthy rats served as the control (C) group. Retinal function and morphology were detected at 1, 7, 14 and 30 d post-occlusion. Furthermore, the expression of vascular endothelial growth factor (VEGF-α) was detected by immunofluorescent staining.

RESULTS

Full-field electroretinography (ffERG) revealed that the amplitude of the b-wave (dark-adaptation 3.0 response), the amplitude of the OPs2 wave and the light-adapted flicker response in the H group were all higher than those in the M group at 7 d post-occlusion (all p < 0.05). The reopen time of occlusive retinal vessels in the H group was 2.235 ± 1.128 d, which was shorter than that in the M group (4.234 ± 2.236 d, p < 0.05). The rats in the H group had a thinner IPL + GCL + NFL and an increased total retina compared with those in the M group at 3 d post-occlusion (p < 0.05), while the rats in the H group had a thicker INL, IPL + GCL + NFL and total retina compared with those at 7, 14 and 30 d post-occlusion (p < 0.05). Moreover, the flow velocity of ear vein blood was increased in the H group compared with that in the M group (p < 0.05). The expression of VEGF-α in the H group was dramatically decreased compared with that in the M group at 1, 7 and 14 d post-occlusion (p < 0.05), while the expression kept in similar level at 30 d post-occlusion (p > 0.05).

CONCLUSIONS

Our findings demonstrate that inhalation of hydrogen gas could alleviate retinal oedema, shorten reopen time and improve retinal function, and the potential mechanism might be related to a decrease in VEGF-α expression.