Aflibercept more effectively weans patients with neovascular age-related macular degeneration off therapy compared with bevacizumab

Targeting endothelial glycolytic reprogramming by tsRNA-1599 for ocular anti-angiogenesis therapy

Rationale: Current treatments for ocular angiogenesis primarily focus on blocking the activity of vascular endothelial growth factor (VEGF), but unfavorable side effects and unsatisfactory efficacy remain issues. The identification of novel targets for anti-angiogenic treatment is still needed. Methods: We investigated the role of tsRNA-1599 in ocular angiogenesis using endothelial cells, a streptozotocin (STZ)-induced diabetic model, a laser-induced choroidal neovascularization model, and an oxygen-induced retinopathy model. CCK-8 assays, EdU assays, transwell assays, and matrigel assays were performed to assess the role of tsRNA-1599 in endothelial cells. Retinal digestion assays, Isolectin B4 (IB4) staining, and choroidal sprouting assays were conducted to evaluate the role of tsRNA-1599 in ocular angiogenesis. Transcriptomic analysis, metabolic analysis, RNA pull-down assays, and mass spectrometry were utilized to elucidate the mechanism underlying angiogenic effects mediated by tsRNA-1599. Results: tsRNA-1599 expression was up-regulated in experimental ocular angiogenesis models and endothelial cells in response to angiogenic stress. Silencing of tsRNA-1599 suppressed angiogenic effects in endothelial cells in vitro and inhibited pathological ocular angiogenesis in vivo. Mechanistically, tsRNA-1599 exhibited little effect on VEGF signaling but could cause reduced glycolysis and NAD+/NADH production in endothelial cells by regulating the expression of HK2 gene through interacting with YBX1, thus affecting endothelial effects. Conclusions: Targeting glycolytic reprogramming of endothelial cells by a tRNA-derived small RNA represents an exploitable therapeutic approach for ocular neovascular diseases.

Trends in Anti-Vascular Endothelial Growth Factor Original Medicare Part B Claims in the United States, 2014-2019

PURPOSE

To characterize trends in use of and expenditure for the intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents aflibercept, ranibizumab, and bevacizumab among the population enrolled in Original Medicare from 2014 to 2019.

METHODS

The Centers for Medicare and Medicaid Services Physician and Other Supplier Public Use File was used to extract Medicare Part B fee-for-service outpatient injection claims data submitted by ophthalmologists. Multivariable linear regression models were used to evaluate the association between reimbursement, ophthalmologist availability, and agent administration rate.

RESULTS

Between 2014 and 2019, 17,588,995 intravitreal injection claims were filed by 4218 US ophthalmologists. Medicare costs for anti-VEGF injections increased from 2.51 B USD in 2014 to 4.02 B USD in 2019. Increased state-level ophthalmologist availability and incremental increases in average reimbursement amounts were found to be significantly associated with a 6.8-fold variation in 2019 overall anti-VEGF injection rates across states.

CONCLUSIONS

Medicare injection rates and costs for anti-VEGF injections have both increased between 2014 and 2019, largely driven by increased aflibercept use. There is a significant association between ophthalmologist availability and anti-VEGF injection rate on the state level, suggesting access to care may contribute to the observed state-level disparities in intravitreal injection rates. Further characterization of factors contributing to the state-level variation in injection rates of individual anti-VEGF agents may help inform interventions promoting equitable access to and use of these drugs.

Patient adherence to therapy after switch to aflibercept from bevacizumab or ranibizumab for treatment-refractory neovascular age-related macular degeneration

PURPOSE

Clinical trials have demonstrated that switching patients from intravitreal bevacizumab (IVB) or ranibizumab (IVR) to aflibercept (IVA) for treatment-refractory neovascular age-related macular degeneration (nAMD) can decrease the injection frequency. This study evaluated whether there was a difference in the rate of injections or nonadherent events after switching therapies.

METHODS

The study comprised a retrospective, cross-sectional analysis of patients treated for nAMD from 2010 to 2018 who received ≥3 intravitreal injections of IVB/IVR prior to switching to IVA because of treatment-refractory nAMD. The treatment index, outcomes, and adherence to treatment were compared between both treatment regimens.

RESULTS

Sixty-two patients (67 eyes) met inclusion criteria. There was no change in the treatment index (0.65 versus 0.66, P = 0.650) or the number of nonadherent events (33 versus 36, P = 0.760) after the switch from IVB/IVR to IVA. Central macular thickness (CMT) increased 7.7%±13.8% in eyes that had a nonadherent event (283±69 µm to 304±75 µm after resuming care, P = 0.039). There was no short-term impact on visual acuity (VA) for this subset of eyes (0.387±0.202 LogMAR versus 0.365±0.156 LogMAR, P = 0.636). Patients who had nonadherent events ended the study with similar VA compared with patients who had no treatment lapses (0.370±0.616 LogMAR versus 0.337±0.638 LogMAR, P = 0.843).

CONCLUSION

Switching from IVB/ IVR to IVA for treatment-refractory nAMD in a real-world setting does not reduce the treatment index or increase adherence to treatment. Although there were short-term anatomical effects resulting from missed treatments, VA remained stable.

Pathologic vs. protective roles of hypoxia-inducible factor 1 in RPE and photoreceptors in wet vs. dry age-related macular degeneration

It has previously been reported that antioxidant vitamins can help reduce the risk of vision loss associated with progression to advanced age-related macular degeneration (AMD), a leading cause of visual impairment among the elderly. Nonetheless, how oxidative stress contributes to the development of choroidal neovascularization (CNV) in some AMD patients and geographic atrophy (GA) in others is poorly understood. Here, we provide evidence demonstrating that oxidative stress cooperates with hypoxia to synergistically stimulate the accumulation of hypoxia-inducible factor (HIF)-1α in the retinal pigment epithelium (RPE), resulting in increased expression of the HIF-1-dependent angiogenic mediators that promote CNV. HIF-1 inhibition blocked the expression of these angiogenic mediators and prevented CNV development in an animal model of ocular oxidative stress, demonstrating the pathological role of HIF-1 in response to oxidative stress stimulation in neovascular AMD. While human-induced pluripotent stem cell (hiPSC)-derived RPE monolayers exposed to chemical oxidants resulted in disorganization and disruption of their normal architecture, RPE cells proved remarkably resistant to oxidative stress. Conversely, equivalent doses of chemical oxidants resulted in apoptosis of hiPSC-derived retinal photoreceptors. Pharmacologic inhibition of HIF-1 in the mouse retina enhanced-while HIF-1 augmentation reduced-photoreceptor apoptosis in two mouse models for oxidative stress, consistent with a protective role for HIF-1 in photoreceptors in patients with advanced dry AMD. Collectively, these results suggest that in patients with AMD, increased expression of HIF-1α in RPE exposed to oxidative stress promotes the development of CNV, but inadequate HIF-1α expression in photoreceptors contributes to the development of GA.

Research progress on diagnosing retinal vascular diseases based on artificial intelligence and fundus images

As the only blood vessels that can directly be seen in the whole body, pathological changes in retinal vessels are related to the metabolic state of the whole body and many systems, which seriously affect the vision and quality of life of patients. Timely diagnosis and treatment are key to improving vision prognosis. In recent years, with the rapid development of artificial intelligence, the application of artificial intelligence in ophthalmology has become increasingly extensive and in-depth, especially in the field of retinal vascular diseases. Research study results based on artificial intelligence and fundus images are remarkable and provides a great possibility for early diagnosis and treatment. This paper reviews the recent research progress on artificial intelligence in retinal vascular diseases (including diabetic retinopathy, hypertensive retinopathy, retinal vein occlusion, retinopathy of prematurity, and age-related macular degeneration). The limitations and challenges of the research process are also discussed.