Targeting Angiopoietin in Retinal Vascular Diseases: A Literature Review and Summary of Clinical Trials Involving Faricimab

Management of treatment-naïve diabetic macular edema patients: Review of real-world clinical data

The high prevalence of Diabetic macular edema (DME) is a real global health problem. Its complex pathophysiology involves different pathways. Over the last decade, the introduction of intravitreal treatments has dramatically changed the management and prognosis of DME. Among the different treatment options, inhibitors of vascular endothelial growth factor (anti-VEGF) and intravitreal steroids implants represent the first-line therapy of DME. We conducted a review of electronic databases to compile the available evidence about the clinical management of DME in a clinical setting, with a special focus on treatment-naïve patients. Anti-VEGF therapies represent a valuable option for treating DME patients. However, many patients do not respond properly to this treatment and, due to its administration regimen, many patients receive suboptimal treatment in real life. Current evidence demonstrated that in patients with DME, DEX-i improved significantly both anatomic and visual outcomes. Besides eyes with insufficient anti-VEGF respond or recalcitrant DME cases, DEX-i can be effectively and safely used in treatment-naïve DME patients as first line therapy. DEX-i may be considered first line therapy in different clinical scenarios, such as DME eyes with a greater inflammatory component, patients with cardiovascular events, vitrectomized eyes, or those requiring cataract surgery. In conclusion, there are still many points for improvement pending in the clinical management of the patient with DME. Since DME treatment must follow a patient-tailored approach, selecting the best therapeutic approach for each patient requires a good understanding of the pathophysiology of DME.

Impaired pericyte-Müller glia interaction via PDGFRβ suppression aggravates photoreceptor loss in a rodent model of light-induced retinal injury

AIM

To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptor β (PDGFRβ) signaling pathway in retinal pericytes on photoreceptor loss and Müller glial response.

METHODS

Sprague-Dawley rats were exposed to intense light to induce retinal injury. Neutralizing antibody against PDGFRβ were deployed to block the signaling pathway in retinal pericytes through intravitreal injection. Retinal histology and Müller glial reaction were assessed following light injury. In vitro, normal and PDGFRβ-blocked retinal pericytes were cocultured with Müller cell line (rMC-1) to examine morphological and protein expression changes upon supplementation with light-injured supernatants of homogenized retinas (SHRs).

RESULTS

PDGFRβ blockage 24h prior to intense light exposure resulted in a significant exacerbation of photoreceptor loss. The upregulation of GFAP and p-STAT3, observed after intense light exposure, was significantly inhibited in the PDGFRβ blockage group. Further upregulation of cytokines monocyte chemoattractant protein 1 (MCP-1) and interleukin-1β (IL-1β) was also observed following PDGFRβ inhibition. In the in vitro coculture system, the addition of light-injured SHRs induced pericyte deformation and upregulation of proliferating cell nuclear antigen (PCNA) expression, while Müller cells exhibited neuron-like morphology and expressed Nestin. However, PDGFRβ blockage in retinal pericytes abolished these cellular responses to light-induced damage, consistent with the in vivo PDGFRβ blockage findings.

CONCLUSION

Pericyte-Müller glia interaction plays a potential role in the endogenous repair process of retinal injury. Impairment of this interaction exacerbates photoreceptor degeneration in light-induced retinal injury.

Role of Plasma Angiopoietin-1 and VEGF Levels as Potential Biomarkers in Chronic Central Serous Chorioretinopathy with Macular Neovascularization

To evaluate the plasma levels of angiopoietin-1 and vascular endothelial growth factor (VEGF) and their association with macular neovascularization (MNV) in patients with chronic central serous chorioretinopathy (cCSC). Correlations between plasma cytokine levels, CSC duration, and mean choroidal thickness (CT) were also investigated. Of the 59 patients with cCSC, 10 patients with MNV secondary to cCSC and 10 patients with cCSC without MNV were enrolled in the study. The control group included 15 healthy volunteers matched for age, sex, smoking status, and comorbidities. Chronic CSC was diagnosed based on typical findings on swept-source optical coherence tomography (OCT), fundus fluorescein angiography, and indocyanine green angiography. Additionally, all patients underwent OCT angiography to help detect MNV. Plasma angiopoietin-1 and VEGF levels were assessed using multiplex immunoassay. The plasma angiopoietin-1 levels differed between the 3 groups (p = 0.005). The angiopoietin-1 levels were lower in patients with cCSC with MNV than in controls (p = 0.006). There were no differences in the plasma VEGF levels between all the 3 groups (p = 0.329). The VEGF levels were negatively correlated with mean CT in cCSC patients with MNV (rho = -0.683, p = 0.042) but correlated positively with disease duration in patients with cCSC without MNV (rho = 0.886, p = 0.003). Our study confirms that MNV is a common complication of cCSC and provides new insights into the role of angiopoietin-1 in cCSC and MNV. Reduced angiopoietin-1 levels in cCSC patients, regardless of MNV status, highlight the importance of the Ang-Tie2 pathway in disease pathogenesis and may point to new therapeutic targets and future novel treatments to improve the management of these patients.

VEGF-A165a and angiopoietin-2 differently affect the barrier formed by retinal endothelial cells

Exposure to VEGF-A165a over several days leads to a persistent dysfunction of the very tight barrier formed by immortalized endothelial cells of the bovine retina (iBREC). Elevated permeability of the barrier is indicated by low cell index values determined by electric cell-substrate impedance measurements, by lower amounts of claudin-1, and by disruption of the homogenous and continuous staining of vascular endothelial cadherin at the plasma membrane. Because of findings that suggest modulation of VEGF-A's detrimental effects on the inner blood-retina barrier by the angiogenic growth factor angiopoietin-2, we investigated in more detail in vitro whether this growth factor indeed changes the stability of the barrier formed by retinal endothelial cells or modulates effects of VEGF-A. In view of the clinical relevance of anti-VEGF therapy, we also studied whether blocking VEGF-A-driven signaling is sufficient to prevent barrier dysfunction induced by a combination of both growth factors. Although angiopoietin-2 stimulated proliferation of iBREC, the formed barrier was not weakened at a concentration of 3 nM: Cell index values remained high and expression or subcellular localization of claudin-1 and vascular endothelial cadherin, respectively, were not affected. Angiopoietin-2 enhanced the changes induced by VEGF-A165a and this was more pronounced at lower concentrations of VEGF-A165a. Specific inhibition of the VEGF receptors with tivozanib as well as interfering with binding of VEGF-A to its receptors with bevacizumab prevented the detrimental effects of the growth factors; dual binding of angiopoietin-2 and VEGF-A by faricimab was marginally more efficient. Uptake of extracellular angiopoietin-2 by iBREC can be efficiently prevented by addition of faricimab which is also internalized by the cells. Exposure of the cells to faricimab over several days stabilized their barrier, confirming that inhibition of VEGF-A signaling is not harmful to this cell type. Taken together, our results confirm the dominant role of VEGF-A165a in processes resulting in increased permeability of retinal endothelial cells in which angiopoietin-2 might play a minor modulating role.

Short-term outcomes of intravitreal faricimab for refractory neovascular age-related macular degeneration

PURPOSE

To assess the short-term outcomes of intravitreal faricimab (IVF) for previously treated refractory neovascular age-related macular degeneration (nAMD) in a real-world setting.

METHODS

A retrospective monocentric study including 44 eyes treated with an upload of 4 × monthly intravitreal injections (IVI) of faricimab 6 mg/0.05 mL and followed for 4 weeks after last IVI (16 W). Patients were switched to IVF after treatment with at least three other anti-vascular endothelial growth factors (anti-VEGF). Main outcome measures included best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and retinal fluid distribution.

RESULTS

44 eyes of 44 patients with previously treated refractory nAMD (63% males) were included. Mean age was 79 ± 7 years. The total number of previous anti-VEGF before switching to IVF was 32 ± 15 IVIs/eye. BCVA (logMAR) improved significantly from 0.65 ± 0.26 to 0.50 ± 0.23 at 16 W (p < 0.01). CMT (µm) decreased significantly from 422 ± 68 to 362 ± 47 at 16 W (p < 0.01). SFCT did not change significantly at 16 W (p = 0.06). The number of eyes with subretinal fluid (SRF) decreased significantly from 29 (65%) to 13 (29%) at 16 W (p = 0.001). There were no significant changes regarding the distribution of intraretinal fluid or pigment epithelial detachment (p > 0.05). A complete fluid resolution was achieved in 8 eyes (18%). No adverse events were noticed.

CONCLUSION

In the short term, IVF led to a significant decrease in CMT as well as a significant improvement of BCVA and thus appears to be an effective treatment option for previously treated refractory nAMD without relevant adverse effects.

Changes in Ocular Blood Flow After Intravitreal Injection for Diabetic Macular Edema Between Aflibercept and Faricimab

Purpose

In this study, we aimed to evaluate and compare the effects of intravitreal aflibercept (IVA) and intravitreal faricimab (IVF) injections on the blood flow of retinal vessels in the peripapillary region and optic nerve head (ONH) in eyes with diabetic macular edema (DME) using laser speckle flowgraphy (LSFG).

Patients and Methods

This study included 20 eyes of 18 patients treated with IVA and 15 eyes of 11 patients treated with IVF for DME. The mean blur rate (MBR) of the ONH and retinal artery and vein of the peripapillary region were measured using LSFG at baseline and 1 month after injection. Central retinal thickness (CRT) and best-corrected visual acuity (BCVA) were measured for all patients.

Results

CRT decreased significantly in both IVA-treated (p = 0.0003) and IVF-treated groups (p = 0.0004). Some of the MBR-related parameters of the ONH, such as MBR of all areas (MA), MBR of vascular areas (MV), and MBR of tissue areas (MT), decreased significantly 1 month after IVA and IVF compared to baseline values (MA of IVA, p < 0.0001; MT of IVA, p = 0.0220; MA of IVF, p = 0.0002; MT of IVF, p = 0.0461). MBR of the retinal artery (MBR-A) and vein (MBR-V) also decreased significantly 1 month after IVA and IVF compared with baseline values (MBR-A of IVA, p = 0.0002; MBR-V of IVA, p = 0.0010; MBR-A of IVF, p = 0.0368). No significant difference in ocular perfusion was observed between the IVA-treated and IVF-treated groups.

Conclusion

Intravitreal injection led to a reduction in ocular blood flow in both retinal peripapillary vessels and the ONH in both IVA-treated and IVF-treated groups. No significant difference was observed in MBR reduction between the IVA-treated and IVF-treated groups. Our findings warrant further long-term investigations to reveal differences between aflibercept and faricimab.

Changes in Macular Pigment Optical Density after Intravitreal Faricimab in Neovascular Age-Related Macular Degeneration: A Pilot Study

Background: This study aimed to evaluate the effects of faricimab intravitreal injections in patients with exudative age macular degeneration (nAMD) after the loading dose using spectral domain optical coherence tomography (SD-OCT) and macular pigment optical density (MPOD). Methods: In this observational prospective study, we enlisted a total of 12 consecutive eyes of 12 patients (six females, six males; mean age 70.47 ± 2.46 years) affected by nAMD who consecutively presented to the Eye Clinic of the University of Naples "Federico II" and Monaldi Hospital of Naples, from June 2023 to December 2023. All patients received four once-monthly intravitreal injections of faricimab (6 mg/0.05 mL) (loading phase). At baseline and 1 month after the fourth faricimab monthly injection, all patients underwent assessment of best correct visual acuity (BCVA) and ophthalmic examination, including slit-lamp biomicroscopy, intraocular pressure (IOP), fundus biomicroscopy, SD-OCT, and MPOD. Results: A total of 12 eyes of 12 patients (six women, six men; mean age 70.47 ± 2.46 years) were included in this study. A statistically significant raise in BCVA and MOPD parameters was shown between baseline and after the loading phase (p < 0.001). Conclusions: Intravitreal injections of faricimab led in the short term to a significant functional and MPOD improvement along with a decrease in central macular thickness (CMT) and thus appears to be an effective treatment option without relevant adverse effects. MOPD may be considered as a prognostic factor associated with a good visual prognosis after intravitreal injections treatment.

Long-acting delivery and therapies for neovascular age-related macular degeneration

INTRODUCTION

Neovascular age-related macular degeneration (nAMD) represents a leading cause of severe visual impairment in individuals over 50 years of age in developed nations. Intravitreal anti-vascular endothelial growth factor (VEGF) injections have become the standard of care for treating nAMD; however, monthly or bimonthly dosing represents significant time and cost burden due to the disease's chronic nature and limited medication half-life.

AREAS COVERED

This review summarizes innovative therapeutics and delivery methods for nAMD. Emerging methods for extended drug delivery include high molar concentration anti-VEGF drugs, intravitreal sustained-release polymers and devices, reservoirs for intravitreal delivery, suprachoroidal delivery of small molecular suspensions and gene therapy biofactories. In addition to VEGF-A, therapies targeting inhibition of VEGF-C and D, the angiopoetin-2 (Ang-2)/Tie-2 pathway, tyrosine kinases, and integrins are reviewed.

EXPERT OPINION

The evolving therapeutic landscape of nAMD is rapidly expanding our toolkit for effective and durable treatment. Recent FDA approvals of faricimab (Vabysmo) and high-dose aflibercept (Eylea HD) for nAMD with potential extension of injection intervals up to four months have been promising developments for patients and providers alike. Further research and innovation, including novel delivery techniques and pharmacologic targets, is necessary to validate the efficacy of developing therapeutics and characterize real-world outcomes, demonstrating promise in expanding treatment durability.

TENAYA and LUCERNE: Two-Year Results from the Phase 3 Neovascular Age-Related Macular Degeneration Trials of Faricimab with Treat-and-Extend Dosing in Year 2

PURPOSE

To evaluate 2-year efficacy, durability, and safety of the bispecific antibody faricimab, which inhibits both angiopoietin-2 and VEGF-A.

DESIGN

TENAYA (ClinicalTrials.gov identifier, NCT03823287) and LUCERNE (ClinicalTrials.gov identifier, NCT03823300) were identically designed, randomized, double-masked, active comparator-controlled phase 3 noninferiority trials.

PARTICIPANTS

Treatment-naive patients with neovascular age-related macular degeneration (nAMD) 50 years of age or older.

METHODS

Patients were randomized (1:1) to intravitreal faricimab 6.0 mg up to every 16 weeks (Q16W) or aflibercept 2.0 mg every 8 weeks (Q8W). Faricimab fixed dosing based on protocol-defined disease activity at weeks 20 and 24 up to week 60, followed up to week 108 by a treat-and-extend personalized treatment interval regimen.

MAIN OUTCOME MEASURES

Efficacy analyses included change in best-corrected visual acuity (BCVA) from baseline at 2 years (averaged over weeks 104, 108, and 112) and proportion of patients receiving Q16W, every 12 weeks (Q12W), and Q8W dosing at week 112 in the intention-to-treat population. Safety analyses included ocular adverse events (AEs) in the study eye through study end at week 112.

RESULTS

Of 1326 patients treated across TENAYA/LUCERNE, 1113 (83.9%) completed treatment (n = 555 faricimab; n = 558 aflibercept). The BCVA change from baseline at 2 years was comparable between faricimab and aflibercept groups in TENAYA (adjusted mean change, +3.7 letters [95% confidence interval (CI), +2.1 to +5.4] and +3.3 letters [95% CI, +1.7 to +4.9], respectively; mean difference, +0.4 letters [95% CI, -1.9 to +2.8]) and LUCERNE (adjusted mean change, +5.0 letters [95% CI, +3.4 to +6.6] and +5.2 letters [95% CI, +3.6 to +6.8], respectively; mean difference, -0.2 letters [95% CI, -2.4 to +2.1]). At week 112 in TENAYA and LUCERNE, 59.0% and 66.9%, respectively, achieved Q16W faricimab dosing, increasing from year 1, and 74.1% and 81.2%, achieved Q12W or longer dosing. Ocular AEs in the study eye were comparable between faricimab and aflibercept groups in TENAYA (55.0% and 56.5% of patients, respectively) and LUCERNE (52.9% and 47.5% of patients, respectively) through week 112.

CONCLUSIONS

Treat-and-extend faricimab treatment based on nAMD disease activity maintained vision gains through year 2, with most patients achieving extended dosing intervals.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Real-World Outcomes of a Loading Phase with Intravitreal Faricimab in Neovascular Age-Related Macular Degeneration (n-AMD) and Diabetic Macular Edema (DME)

INTRODUCTION

The aims of this work were to evaluate the real-world efficacy and safety of a loading dose of intravitreal faricimab in eyes with active neovascular age-related macular degeneration (n-AMD) or diabetic macular edema (DME) and to analyze the treatment outcome in relation to specific biomarkers.

METHODS

Patients with active n-AMD or DME, treated with four monthly intravitreal injections of faricimab, were enrolled in this retrospective, uncontrolled study. Best-corrected visual acuity (BCVA), central subfield thickness (CST), presence of retinal fluid (RF) on optical coherence tomography (OCT), and adverse events were assessed at baseline and at weeks 4, 8, 12, and 16. Predefined biomarkers were evaluated at baseline (BL) and at last visit.

RESULTS

Sixteen eyes of 15 patients with n-AMD (n-AMD group) and 15 eyes of 12 patients with DME (DME group) were included. Mean (± standard deviation) logarithm of minimum angle of resolution (logMAR) BL BCVA changed from 0.68 (± 0.43) to 0.53 (± 0.36; P = 0.13) and from 0.51 (± 0.34) to 0.32 (± 0.24; P: 0.048) at week 16 in n-AMD and DME group, respectively. A statistically significant mean CST reduction was reported in both groups at last visit (n-AMD: - 166.5 μm; P = 0.0009/DME: - 110.8 μm; P = 0.0086). Seventy-five and 33% of eyes with n-AMD and DME respectively achieved complete RF resolution at last visit. Subfoveal inner and outer retinal damage correlated with a lower final BCVA in n-AMD group. The presence of large (> 100 μm) juxtafoveal microaneurysms (MAs) was significantly correlated with a higher chance of residual fluid in eyes with DME.

CONCLUSIONS

Both n-AMD and DME groups achieved satisfactory anatomical results after a loading-dose of intravitreal faricimab. BCVA improvement might be hampered by pre-existing retinal damage in eyes with n-AMD. Large, juxtafoveal MAs might represent a hallmark of a slower anatomical response to the treatment in eyes with DME.

Efficacy, durability, and safety of faricimab up to every 16 weeks in patients with neovascular age-related macular degeneration: 2-year results from the Japan subgroup of the phase III TENAYA trial

PURPOSE

To evaluate 2-year efficacy, durability, and safety of faricimab in the TENAYA Japan subgroup and pooled global TENAYA/LUCERNE cohort of patients with neovascular age-related macular degeneration (nAMD).

METHODS

Subgroup analysis of TENAYA/LUCERNE (NCT03823287/NCT03823300): phase III, multicentre, randomised, active comparator-controlled, double-masked, non-inferiority trials. Treatment-naïve patients aged ≥ 50 years with nAMD were randomised (1:1) to intravitreal faricimab (6.0 mg up to every 16 weeks [Q16W] after 4 initial Q4W doses) or aflibercept (2.0 mg Q8W after 3 initial Q4W doses). Outcomes were assessed through year 2 for the TENAYA Japan subgroup (N = 133) and global pooled TENAYA/LUCERNE cohort (N = 1329).

RESULTS

Vision and anatomic improvements achieved with faricimab at year 1 were maintained over 2 years and were generally comparable between the TENAYA Japan subgroup and pooled TENAYA/LUCERNE cohort. Adjusted mean best-corrected visual acuity (BCVA) change from baseline at year 2 for the TENAYA Japan subgroup and global pooled TENAYA/LUCERNE cohort was +7.1 (3.7-10.5) and +4.4 (3.2-5.5) letters in the faricimab arm, respectively, and +5.2 (1.9-8.6) and +4.3 (3.1-5.4) letters in the aflibercept arm, respectively. At week 112, the proportion of faricimab-treated patients on Q16W dosing was 61.0% and 63.1% in the TENAYA Japan subgroup and pooled TENAYA/LUCERNE cohort. Faricimab was well tolerated through year 2.

CONCLUSION

Year 2 TENAYA Japan subgroup findings for faricimab were generally consistent with the pooled global TENAYA/LUCERNE results in patients with nAMD. Vision and anatomical benefits with faricimab were similar to those with aflibercept but with fewer injections.

Response of Diabetic Macular Edema to Anti-VEGF Medications Correlates with Improvement in Macular Vessel Architecture Measured with OCT Angiography

Purpose

Improvements in best-corrected visual acuity (BCVA) and central subfield thickness (CST) have been well documented after intravitreal injection of anti-VEGF medications in diabetic macular edema (DME); however, their effect on the vasculature of the macula in diabetic retinopathy (DR) remains poorly understood. Our aim was to explore the effect of intravitreal injection of anti-VEGF on parameters of retinal vascular microstructure in DR with OCT angiography (OCTA).

Design

Retrospective study of adult patients with DME that were treated with anti-VEGF intravitreal injections at the University of Illinois at Chicago between 2017 and 2022.

Participants

Forty-one eyes from 30 patients with nonproliferative or proliferative DR with a mean age of 58.83 ± 11.71 years, mean number of intravitreal injections of 2.8 ± 1.4, and mean follow-up of 6.5 ± 1.7 months.

Methods

ImageJ was employed to measure parameters of retinal vascular microstructure in OCTA images, which included perfusion density, vessel-length density (VLD), vessel diameter, and foveal avascular zone (FAZ) characteristics (area, perimeter, and circularity). Student t tests and analysis of variance were used to determine statistical significance.

Main Outcome Measures

A primary analysis was performed comparing the mean of each parameter of all patients as a single group at the beginning and end of the study period. A subgroup analysis was then performed after stratifying patients based on visual improvement, change in CST, prior injection history, and number of injections.

Results

Eyes demonstrated statistical improvement in BCVA logarithm of the minimum angle of resolution score and CST after anti-VEGF treatment. Primary analysis showed a reduction in the vessel diameter of the superficial and deep retinal vasculature, as well as an increase in the circularity of the FAZ within the superficial retinal vasculature after anti-VEGF treatment. Subgroup analysis revealed that eyes with improvement in BCVA exhibited reduced vessel diameter in the superficial retinal vasculature and that eyes with the largest decrease in CST displayed increased perfusion density and VLD in the deep retinal vasculature.

Conclusions

Intravitreal injection of anti-VEGF agents to treat DME improved parameters of retinal vascular microstructure on OCTA over a period of 3 to 9 months, and this effect was most pronounced in eyes that experienced improvement in BCVA and CST.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Pericyte in retinal vascular diseases: A multifunctional regulator and potential therapeutic target

Retinal vascular diseases (RVDs), in particular diabetic retinopathy, retinal vein occlusion, and retinopathy of prematurity, are leading contributors to blindness. The pathogenesis of RVD involves vessel dilatation, leakage, and occlusion; however, the specific underlying mechanisms remain unclear. Recent findings have indicated that pericytes (PCs), as critical members of the vascular mural cells, significantly contribute to the progression of RVDs, including detachment from microvessels, alteration of contractile and secretory properties, and excessive production of the extracellular matrix. Moreover, PCs are believed to have mesenchymal stem properties and, therefore, might contribute to regenerative therapy. Here, we review novel ideas concerning PC characteristics and functions in RVDs and discuss potential therapeutic strategies based on PCs, including the targeting of pathological signals and cell-based regenerative treatments.

Factors Associated with Success of Switching to Faricimab for Neovascular Age-Related Macular Degeneration Refractory to Intravitreal Aflibercept

We investigated the factors associated with the success of switching to faricimab for type 1 macular neovascularization (MNV) refractory to intravitreal aflibercept (IVA). This retrospective cohort study included patients with type 1 MNV who were switched to faricimab because they were refractory to IVA at two centers. The primary endpoint was a more than two-week extension of the treatment interval after 6 months. In addition, factors related to the success or failure of extension and visual and anatomical outcomes were assessed. The analysis included 43 eyes from 43 patients. Extended dosing intervals of >2 weeks were identified in 14 eyes (32.6%). A short dosing interval before switching, absence of polypoidal lesions, and thin central choroidal thickness before switching were identified as factors involved in successful extension. For patients with refractory type 1 MNV, switching to faricimab is a safe and potential option to extend existing dosing intervals.

Associations of Angiopoietin 2 and Vascular Endothelial Growth Factor-A Concentrations with Clinical End Points

BACKGROUND

Angiopoietin 2 regulates endothelial function partially mediated by vascular endothelial growth factor-A (VEGF-A) and may play a role in diabetic kidney disease (DKD). We assessed the association of angiopoietin 2 and VEGF-A with cardiorenal outcomes and investigated the effect of canagliflozin on angiopoietin 2 and VEGF-A concentrations.

METHODS

Two thousand five hundred sixty-five study participants with DKD and available plasma samples treated with canagliflozin or placebo in the Canagliflozin and Kidney Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial were included. Angiopoietin 2 and VEGF-A concentrations were measured at baseline, year 1, and year 3. The primary composite end point of the trial was a composite of kidney failure, doubling of the serum creatinine level, and kidney or cardiovascular death.

RESULTS

Patients with the highest baseline quartile of angiopoietin 2, but not VEGF-A, concentration had the highest risk clinical profile. Treatment with canagliflozin significantly lowered concentrations of angiopoietin 2 (adjusted geometric mean ratio: 0.94; 95% confidence interval, 0.92 to 0.95; P < 0.001), but not VEGF-A. In multivariable-adjusted modeling, each 50% increment in log baseline angiopoietin 2 concentrations was associated with a higher risk of primary composite outcome (hazard ratio, 1.27; 95% confidence interval, 1.13 to 1.43). Angiopoietin 2 change at year 1 compared with baseline explained 10% of the effect of canagliflozin on the primary composite outcome. VEGF-A concentrations were not associated with outcomes, alone or in combination with angiopoietin 2.

CONCLUSIONS

Higher angiopoietin 2 levels were associated with cardiorenal risk among individuals with DKD independent of VEGF-A. Canagliflozin lowered angiopoietin 2 concentrations.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Evaluation of the Effects of Canagliflozin on Renal and Cardiovascular Outcomes in Participants With Diabetic Nephropathy, NCT02065791 .

Aflibercept Off-Target Effects in Diabetic Macular Edema: An In Silico Modeling Approach

Intravitreal aflibercept injection (IAI) is a treatment for diabetic macular edema (DME), but its mechanism of action (MoA) has not been completely elucidated. Here, we aimed to explore IAI's MoA and its multi-target nature in DME pathophysiology with an in silico (computer simulation) disease model. We used the Therapeutic Performance Mapping System (Anaxomics Biotech property) to generate mathematical models based on the available scientific knowledge at the time of the study, describing the relationship between the modulation of vascular endothelial growth factor receptors (VEGFRs) by IAI and DME pathophysiological processes. We also undertook an enrichment analysis to explore the processes modulated by IAI, visualized the effectors' predicted protein activity, and specifically evaluated the role of VEGFR1 pathway inhibition on DME treatment. The models simulated the potential pathophysiology of DME and the likely IAI's MoA by inhibiting VEGFR1 and VEGFR2 signaling. The action of IAI through both signaling pathways modulated the identified pathophysiological processes associated with DME, with the strongest effects in angiogenesis, blood-retinal barrier alteration and permeability, and inflammation. VEGFR1 inhibition was essential to modulate inflammatory protein effectors. Given the role of VEGFR1 signaling on the modulation of inflammatory-related pathways, IAI may offer therapeutic advantages for DME through sustained VEGFR1 pathway inhibition.

Recent advances in bioaffinity strategies for preclinical and clinical drug discovery: Screening natural products, small molecules and antibodies

Bioaffinity drug screening strategies have gained popularity in preclinical and clinical drug discovery for natural products, small molecules and antibodies owing to their superior selectivity, the large number of compounds to be screened and their ability to minimize the time and expenses of the drug discovery process. This paper provides a systematic summary of the principles of commonly used bioaffinity-based screening methods, elaborates on the success of bioaffinity in clinical drug development and summarizes the active compounds, preclinical drugs and marketed drugs obtained through affinity screening methods. Owing to the high demand for new drugs, bioaffinity-guided screening techniques will play a greater part in clinical drug development.

Two cases of diabetic macular edema with diminished areas of retinal non-perfusion and microaneurysms after intravitreal faricimab injections

Purpose

To report two cases of diabetic macular edema (DME) treated with intravitreal faricimab injections (IVFs), including the assessment of retinal microaneurysms and extent of retinal capillary non-perfusion using fluorescein angiography (FA) and indocyanine green angiography (IA).

Observations

Case 1: A 72-year-old man presented with aflibercept-resistant DME in the left eye, with a best-corrected visual acuity (BCVA) of 20/16. FA showed areas of retinal capillary non-perfusion and focal leakage in the macular area of the left eye. IA revealed numerous microaneurysms in the temporal region of the macula. Four consecutive monthly IVFs were administered to the left eye, and DME eventually diminished. After the loading phase, the BCVA was maintained at 20/16 with reduced visual distortion. FA showed improvement of macular leakage and stable retinal capillary non-perfusion areas, and the foveal avascular zone was clearly observed. The disappearance of numerous microaneurysms was confirmed on IA images.Case 2: An 80-year-old woman developed DME with macular vein occlusion in the left eye after panretinal laser photocoagulation for proliferative diabetic retinopathy. The patient's BCVA was 20/32. DME was resistant to subtenon triamcinolone injections. FA revealed focal areas of retinal capillary non-perfusion and persistent leakage in the macular area of the left eye. IA revealed scattered microaneurysms within the retinal arcade. Four consecutive monthly IVFs were administered to the left eye, and DME eventually diminished. After the loading phase, the BCVA was maintained at 20/32. FA showed improvement of macular leakage and stable retinal capillary non-perfusion areas. The reduction of microaneurysms was confirmed on IA images.

Conclusions and importance

These case reports highlight the potential of faricimab as an alternative anti-vascular endothelial growth factor drug for treatment-resistant DME, including reduction of retinal microaneurysms and stabilization of the areas of retinal capillary non-perfusion. However, continuation of a robust treatment regimen may be required to achieve these objectives.

Quantifying Fluid and Function in Suboptimal Responders Switched From an Anti-vascular Endothelial Growth Factor (VEGF) to Faricimab

Background Anti-vascular endothelial growth factor (VEGF) injections have been successful in reducing vision loss from neovascular age-related macular degeneration, a leading cause of blindness. Due to the high treatment burden and suboptimal responses, switching to bi-specific faricimab treatment may lead to improved outcomes. Methods This retrospective chart review evaluated if suboptimal responders to anti-VEGF injections had better outcomes when switched to faricimab. Suboptimal responders were defined as patients with a history of >3 months of injections and the presence of fluid after ≥3 injections. The primary endpoints were best-corrected visual acuity, treatment interval, and fluid levels. Visual acuity measurements and optical coherence tomography were performed before each injection. The total fluid area (TFA) was measured using MATLAB 2023a (MathWorks, Natick, MA, USA). Results Nineteen eyes were included in the analysis. After three faricimab injections, average letters increased from 54.5 to 59.0 (SD: 15.3; p<0.05), and the injection interval was extended from 7.6 to 9.3 weeks (SD: 3.9; p<0.01) after four injections. Patients also experienced anatomical retinal changes, with a reduction in the TFA to 47.3% (p<0.005) after the second injection and a reduction in pigment epithelial detachment height to 82.3% (p<0.005) after one injection. The central subfield thickness was significantly reduced after the second injection (90.6% (SD: 17.6%) p<0.05). Conclusion Switching to faricimab after a suboptimal anti-VEGF response results in improvements in visual acuity, reduced treatment burden, and reduced fluid levels.

Ang-1, Ang-2, and Tie2 are diagnostic biomarkers for Henoch-Schönlein purpura and pediatric-onset systemic lupus erythematous

Henoch-Schönlein purpura (HSP) and pediatric-onset systemic lupus erythematosus (pSLE) are closely associated with vasculitis and vascular diseases. This study aimed to investigate the clinical diagnostic values of Ang-1, Ang-2, and Tie2 for HSP and pSLE. We surveyed 82 HSP patients, 34 pSLE patients, and 10 healthy children. The expression levels of Ang-1, Ang-2, and Tie2 in the serum and urine were assessed using enzyme-linked immunosorbent assay. The diagnostic values of Ang-1, Ang-2, and Tie2 for HSP and pSLE were evaluated using receiver operating characteristic curve analysis. The results revealed that the serum and urine expression levels of Ang-2 and Tie2 were significantly elevated in HSP and pSLE patients, whereas the Ang-1/Ang-2 values were reduced. Additionally, Ang-1 was highly expressed in the serum and urine of HSP patients and in the serum of pSLE patients. Ang-1, Ang-2, and Tie2 showed differential expression in various types of HSP and pSLE compared with their expression in healthy controls. In summary, Ang-1, Ang-2, and Tie2 can serve as biomarkers for HSP and pSLE. Moreover, Ang-1/Ang-2 values are reduced in HSP and pSLE patients. Ang-1, Ang-2, and Tie2 can be used as biomarkers for HSP and pSLE.

Comparative efficacy and safety of Faricimab and other anti-VEGF therapy for age-related macular degeneration and diabetic macular edema: A systematic review and meta-analysis of randomized clinical trials

INTRODUCTION

A systematic review and meta-analysis were conducted to evaluate the efficacy and the overall safety of Faricimab compared with other anti-vascular endothelial growth factors (VEGF) therapy for neovascular age-related macular degeneration (AMD) and diabetic macular edema (DME).

MATERIALS AND METHODS

A systematic literature search of a comprehensive electronic database was performed to identify randomized clinical trials published from January 2013 to January 2023 for Faricimab in AMD and DME. Weighted mean differences and risk ratios were used to integrate the different studies.

RESULTS

A total of 4 randomized controlled trials (RCTs) with 1678 AMD patients and 3 RCTs with 20 DME patients were included in the meta-analysis.In patients with AMD, a significant difference was found in the number of injections between Faricimab and other anti-VEGF therapy (MD = -2.42, 95% CI [-3.93 to -0.90], P = .002).No significant difference was found for the change in best corrected visual acuity (BVCA), central subfoveal thickness (CST), and gaining 15 or more letters. Similarly, no significant difference was found for adverse events.In patients with DME, a significant difference was observed for CST (MD = -22.41, 95% CI [-29.95 to -14.86], P < .00001) and the number of injections(MD = -0.93, 95% CI [-1.33 to -0.54], P < .00001). No significant difference was found for BVCA and gaining 15 or more letters, and no significant difference was found for adverse events.

CONCLUSIONS

Comprehensive evidence confirms that Faricimab achieves non-inferior or even better CST improvement than other anti-VEGF therapies with extended dosing intervals, but more long-term follow-up studies are needed to support our conclusions.

The real-world efficacy and safety of faricimab in neovascular age-related macular degeneration: the TRUCKEE study - 6 month results

BACKGROUND/OBJECTIVE

Investigate real-world patients receiving faricimab for the treatment of neovascular age-related macular degeneration (nAMD).

SUBJECTS/METHODS

Multicenter, retrospective chart review was conducted on patients treated with faricimab for nAMD from February 2022 to September 2022. Collected data includes background demographics, treatment history, best-corrected visual acuity (BCVA), anatomic changes, and adverse events as safety markers. The main outcome measures are changes in BCVA, changes in central subfield thickness (CST) and adverse events. Secondary outcome measures included treatment intervals and presence of retinal fluid.

RESULTS

After one injection of faricimab, all eyes (n = 376), previously-treated (n = 337) and treatment-naïve (n = 39) eyes demonstrated a + 1.1 letter (p = 0.035), a + 0.7 letter (p = 0.196) and a + 4.9 letter (p = 0.076) improvement in BCVA, respectively, and a - 31.3 μM (p < 0.001), a - 25.3 μM (p < 0.001) and a - 84.5 μM (p < 0.001) reduction in CST, respectively. After three injections of faricimab, all eyes (n = 94), previously-treated (n = 81) and treatment-naïve (n = 13) eyes demonstrated a + 3.4 letter (p = 0.03), a + 2.7 letter (p = 0.045) and a + 8.1 letter (p = 0.437) improvement in BCVA, and a - 43.4 μM (p < 0.001), a - 38.1 μM (p < 0.001) and a - 80.1 μM (p < 0.204) reduction in CST, respectively. One case of intraocular inflammation was observed after four injections of faricimab and resolved with topical steroids. One case of infectious endophthalmitis was treated with intravitreal antibiotics and resolved.

CONCLUSIONS

Faricimab has demonstrated improvement or maintenance of visual acuity for patients with nAMD, along with rapid improvement of anatomical parameters. It has been well-tolerated with low incidence of treatable intraocular inflammation. Future data will continue to investigate faricimab for real-world patients with nAMD.

Tyrosine Kinase Inhibitors and their role in treating neovascular age-related macular degeneration and diabetic macular oedema

The advent of intravitreal anti-VEGF injections has revolutionised the treatment of both neovascular age-related macular degeneration (nAMD or wet AMD) and diabetic macular oedema (DMO). Despite their efficacy, anti-VEGF injections precipitate significant treatment burden for patients, caregivers and healthcare systems due to the high frequency of injections required to sustain treatment benefit. Therefore, there remains an unmet need for lower-burden therapies. Tyrosine kinase inhibitors (TKI) are a novel class of drugs that may have considerable potential in addressing this issue. This review will summarise and discuss the results of various pilot studies and clinical trials exploring the role of TKIs in treatment of nAMD and DMO, highlighting promising candidates and possible challenges in developments.

Immune System, Inflammation and Autoantigens in Wet Age-Related Macular Degeneration: Pathological Significance and Therapeutic Importance

Wet age-related macular degeneration (wAMD) is a chronic inflammation-associated neurodegenerative disease affecting the posterior part of the eye in the aging population. Aging results in the reduced functionality of cells and tissues, including the cells of the retina. Initiators of a chronic inflammatory and pathologic state in wAMD may be a result of the accumulation of inevitable metabolic injuries associated with the maintenance of tissue homeostasis from a young age to over 50. Apart from this, risk factors like smoking, genetic predisposition, and failure to repair the injuries that occur, alongside attempts to rescue the hypoxic outer retina may also contribute to the pathogenesis. Aging of the immune system (immunosenescence) and a compromised outer blood retinal barrier (BRB) result in the exposure of the privileged milieu of the retina to the systemic immune system, further increasing the severity of the disease. When immune-privileged sites like the retina are under pathological stress, certain age- and disease-related conditions may necessitate assistance from cells distant from the resident ones to help restore the functionality of the tissue. As a necessary part of tissue repair, inflammation is a major response to disease and recruits immune cells to the site of damage. We suspect that the specific reparative inflammatory responses are controlled by an autoantigen-T cell-mediated mechanism, a process that may be hindered in wAMD.

5α-Hydroxycostic acid inhibits choroidal neovascularization in rats through a dual signalling pathway mediated by VEGF and angiopoietin 2

BACKGROUND

5α-Hydroxycostic acid is a eudemane sesquiterpene that is isolated from the natural plant, Laggera alata. It exerts anti-inflammatory and anti-angiogenic effects on human breast cancer cells, but its role and underlying mechanism in choroidal neovascularization (CNV) are still unclear. We conducted a study to verify that 5α-Hydroxycostic acid can inhibit the formation and leakage of CNV, and describe the possible dual pathway by which it exerts its inhibitory effects in this process.

METHODS

An in vitro model of choroidal neovascularization was established using VEGF164, while a rat model of choroidal neovascularization was established using a 532 nm laser. In both models, the effects of 5α-Hydroxycostic acid in vivo and in vitro were evaluated to determine its inhibitory effect on abnormal cell proliferation, migration and tubule formation, as well as its effect on pathological changes in choroidal tissues and the area of neovascularization leakage in rats. The levels of components in the VEGF/VEGFR and Ang2/Tie2 signaling pathways were measured in tissues and cells.

RESULTS

In vitro experiments have shown that 5α-Hydroxycostic acid can inhibit abnormal cell proliferation, migration and angiogenesis. Additionally, 5α-Hydroxycostic acid enhances cell adhesion by inhibiting the phosphorylation pathways of VEGFR2 and Tie2. In vivo experiments demonstrated that 5α-Hydroxycostic acid has a positive therapeutic effect on choroidal neovascularization in rats. It can effectively reduce vascular leakage, consistent with the results of the cell experiments.

CONCLUSION

5α-Hydroxycostic acid can inhibit choroidal neovascularization by interfering with the VEGF- and Ang2/Tie2-related pathways, and it may be a good candidate drug for treating CNV.

Anti-VEGF Drugs in Age-Related Macular Degeneration: A Focus on Dosing Regimen-Related Safety and Efficacy

Age-related macular degeneration (AMD) is one of the main causes of visual impairment and severe visual loss, and can progress to two advanced forms-neovascularization and atrophic. The field of anti-AMD drugs has undergone huge developments in recent years, from single-target intravitreal administration to current clinical studies with multi-target and non-invasive agents, offering interesting new pharmacological opportunities for the treatment of this disease. Hence, we summarize some of the approved anti-vascular endothelial growth factor (VEGF) drugs for neovascular AMD, especially their structural characteristics, clinical manifestations, dosing regimens, and safety issues of the anti-VEGF drugs highlighted. In addition, advances in atrophic AMD drug research are also briefly described.

Assessment of Inner Blood-Retinal Barrier: Animal Models and Methods

Proper functioning of the neural retina relies on the unique retinal environment regulated by the blood-retinal barrier (BRB), which restricts the passage of solutes, fluids, and toxic substances. BRB impairment occurs in many retinal vascular diseases and the breakdown of BRB significantly contributes to disease pathology. Understanding the different molecular constituents and signaling pathways involved in BRB development and maintenance is therefore crucial in developing treatment modalities. This review summarizes the major molecular signaling pathways involved in inner BRB (iBRB) formation and maintenance, and representative animal models of eye diseases with retinal vascular leakage. Studies on Wnt/β-catenin signaling are highlighted, which is critical for retinal and brain vascular angiogenesis and barriergenesis. Moreover, multiple in vivo and in vitro methods for the detection and analysis of vascular leakage are described, along with their advantages and limitations. These pre-clinical animal models and methods for assessing iBRB provide valuable experimental tools in delineating the molecular mechanisms of retinal vascular diseases and evaluating therapeutic drugs.

Faricimab in neovascular AMD: first report of real-world outcomes in an independent retina clinic

PURPOSE

Assess short-term real-world outcomes in neovascular aged-related macular degeneration (nAMD) treated with novel faricimab.

METHODS

Retrospective case series of nine patients with nAMD (11 eyes) treated with faricimab between May and November 2022. Treatment-naïve patients and non-naïve patients underwent logMAR best corrected visual acuity (BCVA), optical coherence tomography (OCT) DRI OCT-1 Triton (Topcon Corp, Tokyo, Japan), ultra-widefield (UWF) and fundus autofluorescence (FAF) (California Optomap, Optos plc, Dunfermline, Scotland, UK). Previous treatment intervals, number of intravitreal injections, sub/intra retinal fluid (SRF/IRF), central retinal thickness (CRT) and presence/changes in pigment epithelial detachments (PEDs) were recorded.

RESULTS

Mean baseline BCVA and CRT values of patients who switched from other agents were 0.612 ± 0.75 logMAR and 256.16 ± 12.98 µm respectively, with a mean 36-day previous treatment interval. The median number of other previous anti-VEGF intravitreal injections was 8. Mean BCVA at one month significantly improved to 0.387 ± 0.54 logMAR, as well as CRT values which decreased to 245.43 ± 15.34 µm. In the 3 naïve patients, mean baseline BVCA and CRT values were 0.33 ± 0.29 and 874.67 ± 510.86 µm, respectively. At one month follow-up, mean BCVA improved to 0.30 ± 0.29 logMAR and mean CRT was 536.04 ± 36.15 µm. Overall, a significant improvement in BCVA of 0.21 ± 41 logMAR and 238.44 ± 114.9 µm was achieved at one month after the first faricimab intravitreal injection. In addition, a complete resolution of SRF was observed in 6 out of 8 eyes (75%) and of IRF in 2 out of 3 eyes (66.67%), respectively. Drusenoid PED morphology changes were observed in all patients and no drug-related adverse events were observed.

CONCLUSION

Real-world outcomes showed improvement in BCVA and anatomic parameters at an early timepoint, demonstrating the efficacy and durability of faricimab in nAMD patients. Larger numbers of patients and longer follow-up are needed to determine whether the loading dose is required in all, what percentage of patients experience an improvement, and whether improvement it is maintained.

Fc-Engineered Therapeutic Antibodies: Recent Advances and Future Directions

Monoclonal therapeutic antibodies have revolutionized the treatment of cancer and other diseases. Fc engineering aims to enhance the effector functions or half-life of therapeutic antibodies by modifying their Fc regions. Recent advances in the Fc engineering of modern therapeutic antibodies can be considered the next generation of antibody therapy. Various strategies are employed, including altering glycosylation patterns via glycoengineering and introducing mutations to the Fc region, thereby enhancing Fc receptor or complement interactions. Further, Fc engineering strategies enable the generation of bispecific IgG-based heterodimeric antibodies. As Fc engineering techniques continue to evolve, an expanding portfolio of Fc-engineered antibodies is advancing through clinical development, with several already approved for medical use. Despite the plethora of Fc-based mutations that have been analyzed in in vitro and in vivo models, we focus here in this review on the relevant Fc engineering strategies of approved therapeutic antibodies to finetune effector functions, to modify half-life and to stabilize asymmetric bispecific IgGs.

The novel angiogenesis regulator circFAM169A promotes the metastasis of colorectal cancer through the angiopoietin-2 signaling axis

BACKGROUND

Angiogenesis plays an important role in the metastasis of cancers. However, the mechanisms whereby circular RNAs (circRNAs) regulate angiogenesis and affect cancer metastasis are still unclear.

METHODS

We used gene set variation and Spearman's correlation analyses to identify novel angiogenesis-related circRNAs, including circFAM169A. The Kyoto Encyclopedia of Genes and Genomes and Gene Ontology were used to assess the potential biological function of circFAM169A. A quantitative reverse transcription-PCR (qRT-PCR) analysis of 20 pairs of colorectal cancer (CRC) samples was performed to detect the expression level of circFAM169A. Transwell assays, tube formation assays, and nude mouse metastatic tumor models were used to study the function of circFAM169A in CRC. qRT-PCR, dual-luciferase reporter gene assay, RNA antisense purification assay, and Western blot were performed to analyze the competing endogenous RNA mechanism of circFAM169A in promoting CRC angiogenesis.

RESULTS

circFAM169A was highly correlated with the hallmark of angiogenesis in CRC patients. It was up-regulated in liver metastasized CRC patients. circFAM169A overexpression promoted the angiogenesis, migration, and invasion of CRC cells while its down-regulation had the opposite effects. In vivo mouse models further highlighted the pro-metastatic role of circFAM169A in CRC. More importantly, we discovered that circFAM169A enhances the expression of angiopoietin-2 by binding to miR-518a-5p.

Targeted long-term noninvasive treatment of choroidal neovascularization by biodegradable nanoparticles

Choroidal neovascularization (CNV) is the main cause of vision loss in patients with wet age-related macular degeneration (AMD). Currently, treatment of these conditions requires repeated intravitreal injections, which may lead to complications such as infection and hemorrhage. So, we have developed a noninvasive method for treating CNV with nanoparticles, namely, Angiopoietin1-anti CD105-PLGA nanoparticles (AAP NPs), which targets the CNV to enhance drug accumulation at the site. These nanoparticles, with PLGA as a carrier, can slowly release encapsulated Angiopoietin 1 (Ang 1) and target the choroidal neovascularization marker CD105 to enhance drug accumulation, increases vascular endothelial cadherin (VE-cadherin) expression between vascular endothelial cells, effectively reduce neovascularization leakage and inhibit Angiopoietin 2(Ang 2) secretion by endothelial cells. In a rat model of laser-induced CNV, intravenous injection of AAP NPs exerted a good therapeutic effect in reducing CNV leakage and area. In short, these synthetic AAP NPs provide an effective alternative treatment for AMD and meet the urgent need for noninvasive treatment in neovascular ophthalmopathy. STATEMENT OF SIGNIFICANCE: This work describes the synthesis, injection-mediated delivery, in vitro and in vivo efficacy of targeted nanoparticles with encapsulated Ang1; via these nanoparticles, the drug can be targeted to choroidal neovascularization lesions for continuous treatment. The release of Ang1 can effectively reduce neovascularization leakage, maintain vascular stability, and inhibit Ang2 secretion and inflammation. This study provides a new approach for the treatment of wet age-related macular degeneration.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

Faricimab Effectively Resolves Intraretinal Fluid and Preserves Vision in Refractory, Recalcitrant, and Nonresponsive Neovascular Age-Related Macular Degeneration

PURPOSE

To evaluate the functional and anatomic outcomes of faricimab treatment in patients with neovascular age-related macular degeneration (nAMD) who are unresponsive to other anti-vascular endothelial growth factor (VEGF) therapies.

METHODS

A retrospective interventional study was conducted on patients with refractory nAMD who were initially treated with intravitreal bevacizumab, ranibizumab, or aflibercept. These patients were switched to monthly faricimab injections. The central subfield thickness (CST), intraretinal fluid (IRF) or subretinal fluid (SRF) height, and visual acuities were compared before and after faricimab treatment.

RESULTS

A total of 13 eyes (eight right eyes and five left eyes) from 11 patients were followed for 10.4 ± 6.9 months after bevacizumab treatment and 40.3 ± 28.7 months after aflibercept treatment before switching to faricimab. The follow-up time for patients receiving a mean number of 3.7 ± 1.3 faricimab injections was 3.4 ± 1.2 months. The overall median CST was reduced by 18µm (p=0.001) from 342µm to 318µm, along with a reduction of 89µm (p=0.03) in IRF/SRF height from 97µm to 40µm. Following three consecutive injections, the CST showed a significant reduction of 21.5µm (p=0.004) from 344µm to 322.5µm, and IRF/SRF height was reduced by 89µm (p=0.03) from 104µm to 18.5µm. The intraretinal fluid size decreased and leakage stopped, as seen on fluorescein angiography. Visual acuity remained stable after switching to faricimab treatment (0.59 ± 0.45 logMAR vs 0.58 ± 0.45 logMAR, p=1).

CONCLUSIONS

Faricimab has proven to be an effective treatment for nAMD patients resistant to other anti-VEGF agents. It demonstrates significant anatomical improvement and vision preservation in this challenging patient population.

Faricimab for the Treatment of Diabetic Macular Edema and Neovascular Age-Related Macular Degeneration

Nowadays; intravitreal anti-vascular endothelial growth factor (VEGF) drugs are considered the first-line therapeutic strategy for treating macular exudative diseases; including wet age-related macular degeneration (w-AMD) and diabetic macular edema (DME). Despite the important clinical achievements obtained by anti-VEGF drugs in the management of w-AMD and DME; some limits still remain; including high treatment burden; the presence of unsatisfactory results in a certain percentage of patients and long-term visual acuity decline due to complications such as macular atrophy and fibrosis. Targeting the angiopoietin/Tie (Ang/Tie) pathway beyond the VEGF pathway may be a possible therapeutic strategy; which may has the potential to solve some of the previous mentioned challenges. Faricimab is a new; bispecific antibody targeting both VEGF-A and the Ang-Tie/pathway. It was approved by FDA and; more recently; by EMA for treating w-AMD and DME. Results from phase III trials TENAYA and LUCERNE (w-AMD) and RHINE and YOSEMITE (DME) have shown the potential of faricimab to maintain clinical efficacy with more prolonged treatment regimens compared to aflibercept (12 or 16 weeks) with a a good safety profile.

Impact of Angiopoietin-2 on Kidney Diseases

Background

Angiopoietins (Ang) are essential angiogenic factors involved in angiogenesis, vascular maturation, and inflammation. The most studied angiopoietins, angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2), behave antagonistically to each other in vivo to sustain vascular endothelium homeostasis. While Ang-1 typically acts as the endothelium-protective mediator, its context-dependent antagonist Ang-2 can promote endothelium permeability and vascular destabilization, hence contributing to a poor outcome in vascular diseases via endothelial injury, vascular dysfunction, and microinflammation. The pathogenesis of kidney diseases is associated with endothelial dysfunction and chronic inflammation in renal diseases.

Summary

Several preclinical studies report overexpression of Ang-2 in renal tissues of certain kidney disease models; additionally, clinical studies show increased levels of circulating Ang-2 in the course of chronic kidney disease, implying that Ang-2 may serve as a useful biomarker in these patients. However, the exact mechanisms of Ang-2 action in renal diseases remain unclear.

Key Messages

We summarized the recent findings on Ang-2 in kidney diseases, including preclinical studies and clinical studies, aiming to provide a systematic understanding of the role of Ang-2 in these diseases.

Elucidating glial responses to products of diabetes-associated systemic dyshomeostasis

Diabetic retinopathy (DR) is a leading cause of blindness in working age adults. DR has non-proliferative stages, characterized in part by retinal neuroinflammation and ischemia, and proliferative stages, characterized by retinal angiogenesis. Several systemic factors, including poor glycemic control, hypertension, and hyperlipidemia, increase the risk of DR progression to vision-threatening stages. Identification of cellular or molecular targets in early DR events could allow more prompt interventions pre-empting DR progression to vision-threatening stages. Glia mediate homeostasis and repair. They contribute to immune surveillance and defense, cytokine and growth factor production and secretion, ion and neurotransmitter balance, neuroprotection, and, potentially, regeneration. Therefore, it is likely that glia orchestrate events throughout the development and progression of retinopathy. Understanding glial responses to products of diabetes-associated systemic dyshomeostasis may reveal novel insights into the pathophysiology of DR and guide the development of novel therapies for this potentially blinding condition. In this article, first, we review normal glial functions and their putative roles in the development of DR. We then describe glial transcriptome alterations in response to systemic circulating factors that are upregulated in patients with diabetes and diabetes-related comorbidities; namely glucose in hyperglycemia, angiotensin II in hypertension, and the free fatty acid palmitic acid in hyperlipidemia. Finally, we discuss potential benefits and challenges associated with studying glia as targets of DR therapeutic interventions. In vitro stimulation of glia with glucose, angiotensin II and palmitic acid suggests that: 1) astrocytes may be more responsive than other glia to these products of systemic dyshomeostasis; 2) the effects of hyperglycemia on glia are likely to be largely osmotic; 3) fatty acid accumulation may compound DR pathophysiology by promoting predominantly proinflammatory and proangiogenic transcriptional alterations of macro and microglia; and 4) cell-targeted therapies may offer safer and more effective avenues for DR treatment as they may circumvent the complication of pleiotropism in retinal cell responses. Although several molecules previously implicated in DR pathophysiology are validated in this review, some less explored molecules emerge as potential therapeutic targets. Whereas much is known regarding glial cell activation, future studies characterizing the role of glia in DR and how their activation is regulated and sustained (independently or as part of retinal cell networks) may help elucidate mechanisms of DR pathogenesis and identify novel drug targets for this blinding disease.

VEGF Induces Expression of Genes That Either Promote or Limit Relaxation of the Retinal Endothelial Barrier

The purpose of this study was to identify genes that mediate VEGF-induced permeability. We performed RNA-Seq analysis on primary human retinal endothelial cells (HRECs) cultured in normal (5 mM) and high glucose (30 mM) conditions that were treated with vehicle, VEGF, or VEGF then anti-VEGF. We filtered our RNA-Seq dataset to identify genes with the following four characteristics: (1) regulated by VEGF, (2) VEGF regulation reversed by anti-VEGF, (3) regulated by VEGF in both normal and high glucose conditions, and (4) known contribution to vascular homeostasis. Of the resultant 18 genes, members of the Notch signaling pathway and ANGPT2 (Ang2) were selected for further study. Permeability assays revealed that while the Notch pathway was dispensable for relaxing the barrier, it contributed to maintaining an open barrier. In contrast, Ang2 limited the extent of barrier relaxation in response to VEGF. These findings indicate that VEGF engages distinct sets of genes to induce and sustain barrier relaxation. Furthermore, VEGF induces expression of genes that limit the extent of barrier relaxation. Together, these observations begin to elucidate the elegance of VEGF-mediated transcriptional regulation of permeability.

Platelet‑related parameters as potential biomarkers for the prognosis of sepsis

Early diagnosis and accurate prognosis are key for reducing the fatality rate and medical expenses associated with sepsis. Platelets are involved in the delayed tissue injury that occurs during sepsis. Therefore, the aim of the present study was to investigate the usefulness of platelets and associated parameters as prognostic markers of sepsis. The present study collected patient samples based on The Third International Consensus Definitions for Sepsis and Septic Shock criteria. Platelet-associated parameters were detected by flow cytometry and their correlation with clinical scores and prognoses was analyzed. Considering the association between endothelial cells and platelet activation, levels of plasma tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and angiopoietin-2 (Ang-2) were analyzed by ELISA. The results showed significant differences in platelet P-selectin expression and phosphatidylserine exposure, mitochondrial membrane potential (Mmp)-Index values and plasma levels of TWEAK and Ang-2 between patients and healthy controls (P<0.05). Except for P-selectin and TWEAK levels, all parameters were correlated with clinical scores (acute physiology and chronic health evaluation II and sequential/sepsis-related organ failure assessment). Additionally, platelet Mmp-Index between admission and the end of therapy was only different in non-survivors (P<0.001) and platelet phosphatidylserine exposure was significantly lower in survivors (P=0.006). Therefore, of the parameters tested, the dynamic monitoring of phosphatidylserine exposure, platelet Mmp-Index values and plasma Ang-2 levels had the most potential for the assessment of disease severity and clinical outcomes.

Systemic Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a vasoproliferative vitreoretinal disorder, is the leading cause of childhood blindness worldwide. Although angiogenic pathways have been the main focus, cytokine-mediated inflammation is also involved in ROP etiology. Herein, we illustrate the characteristics and actions of all cytokines involved in ROP pathogenesis. The two-phase (vaso-obliteration followed by vasoproliferation) theory outlines the evaluation of cytokines in a time-dependent manner. Levels of cytokines may even differ between the blood and the vitreous. Data from animal models of oxygen-induced retinopathy are also valuable. Although conventional cryotherapy and laser photocoagulation are well established and anti-vascular endothelial growth factor agents are available, less destructive novel therapeutics that can precisely target the signaling pathways are required. Linking the cytokines involved in ROP to other maternal and neonatal diseases and conditions provides insights into the management of ROP. Suppressing disordered retinal angiogenesis via the modulation of hypoxia-inducible factor, supplementation of insulin-like growth factor (IGF)-1/IGF-binding protein 3 complex, erythropoietin, and its derivatives, polyunsaturated fatty acids, and inhibition of secretogranin III have attracted the attention of researchers. Recently, gut microbiota modulation, non-coding RNAs, and gene therapies have shown promise in regulating ROP. These emerging therapeutics can be used to treat preterm infants with ROP.

Quantitative analysis of tear angiogenic factors in retinopathy of prematurity: a pilot biomarker study

PURPOSE

To determine whether vascular endothelial growth factor (VEGF), angiopoeitin-1 (Ang-1), angiopoetin-2 (Ang-2), and matrix metalloproteinase-9 (MMP-9) can be reliably collected and analyzed from infant tears to aid in the diagnosis of retinopathy of prematurity (ROP) and enhance the ability to objectively monitor its clinical course.

METHODS

In this nonrandomized controlled investigation, tear and saliva samples collected from 20 premature infants during serial ophthalmic examination were analyzed using enzyme-linked immunoassay with results analyzed as a function of disease stage and need for treatment.

RESULTS

Tear volume was directly correlated with corrected gestational age (P < 0.001). Tear VEGF levels from samples corresponding to stage 3 ROP were 47.9% lower (P = 0.006) than in samples corresponding to stage 0-1 and 49.1% lower (P = 0.01) than in samples corresponding to stage 2 ROP. There were no between-group differences after normalizing tear VEGF by saliva VEGF levels. Tear/saliva ratio for Ang-1 was 200% greater (P = 0.042) and tear/saliva ratio for Ang-2 was 165% greater (P = 0.035) in samples corresponding to stage 2 versus stage 0-1 ROP disease. Ang-1/Ang-2 ratio was lower in samples from infants who developed stage 2 or worse ROP than in samples from infants who never developed worse than stage 1 ROP (P = 0.031).

CONCLUSIONS

In this study cohort, cytokines involved in the pathophysiology of ROP could be reliably identified in and analyzed from infant tears, and showed variation with ROP severity.

The effects and mechanisms of ghrelin upon angiogenesis in human coronary artery endothelial cells under hypoxia

Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor (GHSR), has been found to stimulate angiogenesis both in vivo and in vitro. However, the effect of ghrelin upon angiogenesis, and the corresponding mechanisms of ghrelin therein, in human coronary artery endothelial cells (HCAECs) under hypoxia is still unknown. Our study found that ghrelin significantly increased HCAECs proliferation, migration, in vitro angiogenesis, and microvessel sprouting from the aortic ring under hypoxic conditions. The ghrelin-induced angiogenic process was accompanied by vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and endothelial-specific receptor tyrosine kinase (Tie2) expressions. In addition, this angiogenic effect was almost completely inhibited by Ang-2 RNAi and Tie2 RNAi. Pretreatment with the GHSR1a blocker [D-Lys3]-GHRP-6 abolished ghrelin-induced VEGF, Ang-1, Ang-2 and Tie2 expressions and in vitro angiogenesis. In conclusion, this is the first demonstration that ghrelin stimulates HCAECs in vitro angiogenesis through GHSR1a-mediated VEGF, Ang-1, Ang-2 and Tie2 pathways under hypoxic conditions. It indicated that ghrelin might play an important role in myocardial angiogenesis after ischemic injury.

Classification of diabetic retinopathy: Past, present and future

Diabetic retinopathy (DR) is a leading cause of visual impairment and blindness worldwide. Since DR was first recognized as an important complication of diabetes, there have been many attempts to accurately classify the severity and stages of disease. These historical classification systems evolved as understanding of disease pathophysiology improved, methods of imaging and assessing DR changed, and effective treatments were developed. Current DR classification systems are effective, and have been the basis of major research trials and clinical management guidelines for decades. However, with further new developments such as recognition of diabetic retinal neurodegeneration, new imaging platforms such as optical coherence tomography and ultra wide-field retinal imaging, artificial intelligence and new treatments, our current classification systems have significant limitations that need to be addressed. In this paper, we provide a historical review of different classification systems for DR, and discuss the limitations of our current classification systems in the context of new developments. We also review the implications of new developments in the field, to see how they might feature in a future, updated classification.

Vitreous protein networks around ANG2 and VEGF in proliferative diabetic retinopathy and the differential effects of aflibercept versus bevacizumab pre-treatment

Extracellular signalling proteins interact in networks rather than in isolation. In this context we investigated vitreous protein levels, including placental growth factor (PlGF), angiopoietin-2 (ANG2) and vascular endothelial growth factor (VEGF), in patients with proliferative diabetic retinopathy (PDR) with variable disease severities, and after anti-VEGF pre-treatment. Vitreous samples of 112 consecutive patients undergoing vitrectomy for PDR and of 52 non-diabetic patients with macular holes as controls were studied. A subset of the PDR patients were treated with either aflibercept (AFB, n = 25) or bevacizumab (BVZ)/ranibizumab (RZB) (n = 13), before surgery. Antibody-based analysis of 35 proteins (growth factors and cytokines) showed a significant increase in expression levels of 27 proteins in PDR patients as compared to controls. In network analysis of co-regulated proteins, a strong correlation in expression levels between VEGF, PlGF, MCP1 and ANG2 was found, mostly clustered around ANG2. In the AFB treatment group, concentrations of several proteins were decreased, including VEGFR1, whereas interleukin 6 and 8 were increased as compared to untreated PDR patients. The observed differences in vitreous protein levels between the different treatments and untreated PDR patients may underlie differences in clinical outcomes in patients with PDR.

The Role of Angiopoietins in Neovascular Diabetes-Related Retinal Diseases

Diabetic retinopathy is a devastating and frequent complication of poorly controlled diabetes, whose pathogenesis is still only partially understood. Advances in basic research over the last two decades have led to the discovery of angiopoietins, proteins that strongly influence the growth and integrity of blood vessels in many vascular beds, with particular importance in the retina. Angiopoietin 1 (Ang1), produced mostly by pericytes and platelets, and angiopoietin 2 (Ang2), produced mainly by endothelial cells, bind to the same receptor (Tie2), but exert opposing effects on target cells. Ang1 maintains the stability of the mature vasculature, while Ang2 promotes vessel wall destabilization and disruption of the connections between endothelial cells and pericytes. Human retinal endothelial cells exposed to Ang2 show reduced membrane expression of the adhesion molecule VE-cadherin, and patients with proliferative diabetic retinopathy or diabetic macular edema have markedly increased vitreal concentrations of Ang2. Faricimab, a bi-specific antibody simultaneously directed against Ang2 and VEGF, has shown promising results in clinical trials among patients with diabetic retinopathy, and other agents targeting the angiopoietin system are currently in development.

Multi-Scalar Data Integration Links Glomerular Angiopoietin-Tie Signaling Pathway Activation With Progression of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease (ESKD). Prognostic biomarkers reflective of underlying molecular mechanisms are critically needed for effective management of DKD. A three-marker panel was derived from a proteomics analysis of plasma samples by an unbiased machine learning approach from participants (N = 58) in the Clinical Phenotyping and Resource Biobank study. In combination with standard clinical parameters, this panel improved prediction of the composite outcome of ESKD or a 40% decline in glomerular filtration rate. The panel was validated in an independent group (N = 68), who also had kidney transcriptomic profiles. One marker, plasma angiopoietin 2 (ANGPT2), was significantly associated with outcomes in cohorts from the Cardiovascular Health Study (N = 3,183) and the Chinese Cohort Study of Chronic Kidney Disease (N = 210). Glomerular transcriptional angiopoietin/Tie (ANG-TIE) pathway scores, derived from the expression of 154 ANG-TIE signaling mediators, correlated positively with plasma ANGPT2 levels and kidney outcomes. Higher receptor expression in glomeruli and higher ANG-TIE pathway scores in endothelial cells corroborated potential functional effects in the kidney from elevated plasma ANGPT2 levels. Our work suggests that ANGPT2 is a promising prognostic endothelial biomarker with likely functional impact on glomerular pathogenesis in DKD.

Pan-cancer analyses of classical protein tyrosine phosphatases and phosphatase-targeted therapy in cancer

Protein tyrosine phosphatases function in dephosphorylating target proteins to regulate signaling pathways that control a broad spectrum of fundamental physiological and pathological processes. Detailed knowledge concerning the roles of classical PTPs in human cancer merits in-depth investigation. We comprehensively analyzed the regulatory mechanisms and clinical relevance of classical PTPs in more than 9000 tumor patients across 33 types of cancer. The independent datasets and functional experiments were employed to validate our findings. We exhibited the extensive dysregulation of classical PTPs and constructed the gene regulatory network in human cancer. Moreover, we characterized the correlation of classical PTPs with both drug-resistant and drug-sensitive responses to anti-cancer drugs. To evaluate the PTP activity in cancer prognosis, we generated a PTPscore based on the expression and hazard ratio of classical PTPs. Our study highlights the notable role of classical PTPs in cancer biology and provides novel intelligence to improve potential therapeutic strategies based on pTyr regulation.

Aflibercept versus Faricimab in the Treatment of Neovascular Age-Related Macular Degeneration and Diabetic Macular Edema: A Review

Diabetic macular edema (DME) and neovascular age-related macular degeneration (nAMD) are common retinal vascular diseases responsible for most blindness in the working-age and older population in developed countries. Currently, anti-VEGF agents that block VEGF family ligands, including ranibizumab, bevacizumab (off-label use), brolucizumab, and aflibercept, are the first-line treatment for nAMD and DME. However, due to the complex pathophysiological background of nAMD and DME, non-response, resistance during anti-VEGF therapy, and relapses of the disease are still observed. Moreover, frequent injections are a psychological and economic burden for patients, leading to inadequate adhesion to therapy and a higher risk of complications. Therefore, therapeutic methods are strongly needed to develop and improve, allowing for more satisfactory disease management and lower treatment burden. Currently, the Ang/Tie-2 pathway is a promising therapeutic target for retinal vascular diseases. Faricimab is the first bispecific monoclonal antibody for intravitreal use that can neutralize VEGF and Ang-2. Due to the prolonged activity, faricimab allows extending the interval between successive injections up to three or four months in nAMD and DME patients, which can be a significant benefit for patients and an alternative to implanted drug delivery systems.

Ang2-Targeted Combination Therapy for Cancer Treatment

Angiopoietin-2 (Ang2), a member of the angiopoietin family, is widely involved in the process of vascular physiology, bone physiology, adipose tissue physiology and the occurrence and development of inflammation, cardiac hypertrophy, rheumatoid, tumor and other diseases under pathological conditions. Proliferation and metastasis of cancer largely depend on angiogenesis. Therefore, anti-angiogenesis has become the target of tumor therapy. Due to the Ang2 plays a key role in promoting angiogenesis and stability in vascular physiology, the imbalance of its expression is an important condition for the occurrence and development of cancer. It has been proved that blocking Ang2 can inhibit the growth, invasion and metastasis of cancer cells. In recent years, research has been constantly supplemented. We focus on the mechanisms that regulate the expression of Ang2 mRNA and protein levels in different cancers, contributing to a better understanding of how Ang2 exerts different effects in different cancers and stages, as well as facilitating more specific targeting of relevant molecules in cancer therapy. At the same time, the importance of Ang2 in cancer growth, metastasis, prognosis and combination therapy is pointed out. And finally, we will discuss the current investigations and future challenges of combining Ang2 inhibition with chemotherapy, immunotherapy, and radiotherapy to increase its efficacy in cancer patients. This review provides a theoretical reference for the development of new targets and effective combination therapy strategies for cancer treatment in the future.