The Role of Laser Photocoagulation in Treating Diabetic Macular Edema in the Era of Intravitreal Drug Administration: A Descriptive Review

Cost-effectiveness analysis of bispecific antibody faricimab for treatment of neovascular age-related macular degeneration and diabetic macular edema in Japan

OBJECTIVE

To assess the cost-effectiveness of faricimab vs. other anti-vascular endothelial growth factor (anti-VEGF) drugs for treatment of neovascular age-related macular degeneration (nAMD) and diabetic macular edema (DME) in Japan, while considering societal burden associated with treatment.

METHODS

A Markov model for cost-effectiveness analysis of anti-VEGF treatment in patients with nAMD and DME was applied based on cost and utility value data from Japan. Faricimab administered through a treat-and-extend (T&E) regimen was compared with ranibizumab administered pro re nata (PRN) and T&E, aflibercept T&E, brolucizumab T&E, and best supportive care (BSC). Further to treatment costs (public payer perspective), the societal burden (societal perspective), including costs of travel, informal care, and productivity, was assessed.

RESULTS

In treatment of nAMD, lifetime quality-adjusted life years (QALYs) gained were highest with faricimab (faricimab T&E: 6.92, ranibizumab PRN: 6.88, ranibizumab T&E: 6.91, aflibercept T&E: 6.89, brolucizumab T&E: 6.89, BSC: 5.99). From the public payer perspective, the lifetime total cost for faricimab T&E was lower than those for ranibizumab (PRN, T&E) and brolucizumab (T&E), comparable to aflibercept T&E, and higher than BSC (incremental costs: 158,385 and 6,475,511 JPY, respectively). As a result, faricimab was cost-effective or dominant in the treatment of nAMD, excluding BSC. From the societal perspective, faricimab was dominant against all comparators in nAMD. In treatment of DME, QALYs gained were highest with faricimab (faricimab T&E: 8.51, ranibizumab PRN: 8.17, aflibercept PRN: 8.36, ranibizumab T&E: 8.13, BSC: 5.16). From both the public payer and societal perspectives, faricimab was dominant against all comparators in DME.

CONCLUSIONS

When societal burdens were considered, faricimab was dominant in both nAMD and DME against all comparators, suggesting that the extended dosing interval associated with faricimab treatment may alleviate societal burdens and consequently improve patient outcomes.

Localization of fluorescent gold nanoparticles throughout the eye after topical administration

The human eye is a highly intricate sensory organ. When a condition requiring treatment occurs, eyedrops, which represent 90% of all ophthalmic treatments, are most frequently used. However, eyedrops are associated with low bioavailability, with less than 0.02% of therapeutic molecules reaching the anterior chamber. Thus, new delivery systems are required to ensure sufficient drug concentration over time at the target site. Gold nanoparticles are a promising avenue for drug delivery; however, they can be difficult to track in biological systems. Fluorescent gold nanoparticles, which have the same ultrastability and biocompatibility as their nonfluorescent counterpart, could act as an effective imaging tool to study their localization throughout the eye after administration. Thus, this study (1) synthesized and characterized fluorescent gold nanoparticles, (2) validated similar properties between nonfluorescent and fluorescent gold nanoparticles, and (3) determined their localization in the eye after topical application on ex vivo rabbit eyes. The fluorescent gold nanoparticles were synthesized, characterized, and identified in the cornea, iris, lens, and posterior segment of rabbit eyeballs, demonstrating tremendous potential for future drug delivery research.

Short-Chain Fatty Acids and the Gut-Retina Connection: A Systematic Review

The interplay between gut microbiota and retinal health, known as the gut--retina axis, has gained increasing attention in recent years. Short-chain fatty acids (SCFAs), metabolites produced by gut microbiota, have been identified as key mediators of gut-retina communication. This systematic review explores the role of SCFAs in retinal health and their potential impact on the development and progression of retinal diseases, such as diabetic retinopathy (DR), age-related macular degeneration (AMD), and glaucoma. A literature search was conducted across multiple databases, including PubMed, Google Scholar, and Science Direct, to identify studies published between 2014 and December 2024. Studies were included if they investigated the effects of SCFAs on retinal structure, function, or disease pathogenesis in animal models or human subjects. The review included 10 original articles spanning both preclinical and clinical studies. Evidence suggests that SCFAs play a crucial role in maintaining retinal homeostasis through anti-inflammatory and neuroprotective mechanisms. Dysbiosis of the gut microbiota, leading to altered SCFA production, was associated with increased retinal inflammation, oxidative stress, and vascular dysfunction. Furthermore, reduced SCFA levels were linked to the progression of retinal diseases, such as diabetic retinopathy and age-related macular degeneration. Modulation of gut microbiota and SCFA levels through dietary interventions or probiotics may represent a novel therapeutic strategy for preventing or managing retinal diseases. Further research is needed to elucidate the precise molecular mechanisms underlying SCFA-mediated retinal protection and to evaluate the efficacy of targeted therapies in clinical settings.

Efficacy & safety of brolucizumab 6.0 mg versus 3.6 mg in diabetic macular edema

BACKGROUND

Management of Diabetic Macular edema (DME) requires repeated injections. Therefore newer Anti-VEGFs like Brolucizumab with longer durability have been introduced. We compared two different dosages of Brolucizumab, 6.0 mg and 3.6 mg, for their safety & efficacy in treatment of DME, in treatment naïve patients over 52 weeks.

METHOD

A prospective, pilot randomised controlled, single centre, double blinded, two arm comparative study was conducted between Dec 2022 to Apr 2024. The study recruited 82 patients of DME who were randomised into two groups of 41 patients each, one group to be treated with Brolucizumab 6.0 mg in 50 μL and the other to receive 3.6 mg in 30 μL. All patients received the first dose of Brolucizumab at 0 week and were then followed up at every 4 weeks for detailed ophthalmic and OCT macula examination. Those who met the pre-defined re-treatment criteria were re-injected with Brolucizumab, the dose being fixed for each group throughout the study. All patient receiving an injection were further followed up on Day 1, Day 7 and Day 28 to look for any adverse reactions. The efficacy parameters included change in best corrected visusal acuity (BCVA), contrast and central macular thickness (CMT) on Optical Coherence Tomography. The average number of injections recd in each group were also calculated.

RESULTS

The change in BCVA from baseline in 6.0 mg group was 0.54 LogMAR units and 3.6 mg group was 0.59 LogMAR units, which was not statistically significant. The reduction in CMT from baseline in 6.0 mg group was 133.2 µm (μ) and 3.6 mg group was 110.6 μ, which was not statistically significant. The improvement in contrast from baseline in 6.0 mg group was 0.74 and 3.6 mg group was 0.95, with p value of 0.0002. The re-injection interval was 14.21 weeks in 6.0 mg group and 15.56 weeks for 3.6 mg subgroup. The total number of adverse events in both groups were similar at 70 in 6.0 mg group and 47 in 3.6 mg group with only one grade 4 adverse event occurring in each group.

CONCLUSION

The results of present study show that the safety and efficacy of both doses of Brolucizumab, i.e. 6.0 mg and 3.6 mg, for treating diabetic macular edema is similar. Trial registration Study was registered with Clinical trials registry of India (CTRI ref no. CTRI/2023/06/054105), registered on 14 Nov 2022.

Brolucizumab for the Treatment of Diabetic Macular Edema: An Optical Coherence Tomography-Based Analysis

Objectives: The objectives of this study were to evaluate the structural and functional outcomes after the loading phase with brolucizumab in switched patients with diabetic macular edema (DME) and to identify potential predictive biomarkers of treatment response. Methods: A total of 28 eyes with DME, switched to brolucizumab, were retrospectively reviewed. Main outcomes during the follow-up period, up to 6 weeks after the fifth injection, included changes in best-corrected visual acuity (BCVA), central subfield thickness (CST), macular volume, subfoveal choroidal thickness, intraretinal and subretinal fluid (IRF and SRF), cyst dimension including maximal horizontal cyst diameter (MHCD), maximal vertical cyst diameter (MVCD), width-to-height ratio (WHR), foveal avascular zone (FAZ) dimension, and vessel density (VD). Results: At the last follow-up, BCVA was significantly improved (p = 0.003). Significant reduction of CST was demonstrated after each injection time point (p < 0.05), and a dry macula was detected in 64.3% of patients at the last follow-up. The WHR was 1.23 ± 0.46, and a negative correlation to final CST (p < 0.0001) was found. In FAZ and VD analysis, no significant variation was detected. At the last disease activity assessment, the treatment regimen was q12 in 64% of patients. Conclusions: Brolucizumab leads to anatomical and functional improvements in switched eyes affected by DME. WHR may represent a predictive biomarker of treatment response.

Diabetic macular edema (DME): dissecting pathogenesis, prognostication, diagnostic modalities along with current and futuristic therapeutic insights

One of the most common health concerns disturbing people within working years globally is diabetes mellitus (DM). One well-known consequence of DM is vascular damage, which can manifest as macro- and microangiopathy affecting the ocular retina. Therefore, Diabetic macular edema (DME) is a major sight-threatening complication of diabetic retinopathy (DR) worldwide. It is the most prevalent cause of significant vision impairment in diabetic patients. Long-term vision loss can be avoided by following early DME treatment guidelines in everyday life. Hence, there are various therapeutic approaches for DME management. Currently, the first-line treatment for DME is anti-VEGF family drugs, such as ranibizumab, brolucizumab, bevacizumab, and aflibercept. Nevertheless, relapses of the disease, inadequate response, and resistance during anti-VEGF therapy are still seen because of the intricate pathophysiological foundation of the disease. Consequently, there is an excellent requirement for therapeutic approaches to advance and become better at controlling diseases more satisfactorily and require fewer treatments overall. We conducted a thorough literature search in the current review to present a comprehensive overview of the primary data about the current DME therapeutic agents. We also covered the novel advances in DME management and probable future treatments being investigated and developed. This review recommended that Large clinical trials should afford sufficient evidence to support these innovative treatment modalities.

Vascular endothelial growth factor/connective tissue growth factor and proteomic analysis of aqueous humor after intravitreal conbercept for proliferative diabetes retinopathy

AIM

To investigate the role of connective tissue growth factor (CTGF) and vascular endothelial growth factor (VEGF) in the protein profile of the aqueous humor in patients with proliferative diabetic retinopathy (PDR) following intravitreal injection of conbercept.

METHODS

This study included 72 PDR patients and 8 cataract patients as controls. PDR patients were divided into 3 groups according to the intervals of 3, 5, and 7d between intravitreal conbercept (IVC, 0.5 mg/0.05 mL) injection and pars plana vitrectomy (PPV) performed. Aqueous humor samples were collected before and after IVC and PPV for VEGF and CTGF levels detected with enzyme-linked immunosorbent assay (ELISA). The differential proteomics of 10 patients who underwent PPV surgery 5d after IVC and 8 normal controls was studied, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on the data, and the protein interaction network of 23 differential proteins was studied.

RESULTS

Post-IVC, VEGF levels decreased and CTGF levels increased significantly in aqueous humor, with the CTGF/VEGF ratio rising significantly at all intervals. Liquid chromatography tandem mass spectrometry (LC-MS/MS) identified differentially expressed proteins between pre- and post-IVC samples. GO and KEGG analyses revealed involvement in immune response, stress response, complement and coagulation cascades, ferroptosis, and PPAR signaling pathways. PPI analysis highlighted key proteins like APOA1, C3, and transferrin (TF). ELISA assay confirmed the differential expression of proteins such as HBA1, SERPINA1, COL1A1, and ACTB, with significant changes in the IVC groups.

CONCLUSION

The study demonstrates that IVC effectively reduces VEGF levels while increasing CTGF levels, thereby modifying the CTGF/VEGF ratio, and IVC significantly alters the protein profile in the aqueous humor of patients with PDR. Proteomic analysis reveals that these changes are associated with critical biological pathways and protein interactions involved in immune response, stress response, and cellular metabolism.

Laser Treatment for Diabetic Retinopathy: History, Mechanism, and Novel Technologies

Background: Diabetic retinopathy (DR), as a complication of diabetes mellitus (DM), remains a significant contributor to preventable vision impairment in the working-age population. Laser photocoagulation is essential in treating DR in conjunction with anti-vascular endothelial growth factor (VEGF) injection, steroids, and vitrectomy. This review summarizes the history of laser photocoagulation and highlights its current role and long-term effectiveness in real-world conditions. Methods: The National Clinical Trial (NCT), PubMed, Google Scholar, and China National Knowledge Infrastructure (CNKI) databases were searched utilizing combined or individual keywords, and a total of 121 articles were reviewed by the authors. Results: Several novel laser photocoagulation technologies, such as patterned scanning laser, subthreshold micropulse laser, navigated laser, multimodal imaging-guided laser, and retina rejuvenation therapy, substantially decrease the adverse effects and improve the accuracy and security of laser therapy. Numerous studies have demonstrated the outstanding clinical efficacy of combination therapies with pharmacologic treatments like anti-VEGF in treating DR and diabetic macular edema (DME). A 20-year follow-up retrospective study in our center preliminarily demonstrated the long-term effectiveness of conventional laser photocoagulation. Conclusions: More clinical trials are required to confirm the clinical effectiveness of novel laser technologies. Better treatment protocols for the combination therapy may be detailed. Anti-VEGF treatment has better effects, especially for DME and in a short period. But in real-world conditions, given the long-term effectiveness and economic advantages of conventional laser treatment, it should be prioritized over anti-VEGF injection in certain situations.

Effect of ranibizumab combined with laser photocoagulation in the treatment of diabetic macular edema

Objective

To explore the clinical effect of ranibizumab combined with laser photocoagulation (LP) in treating diabetic macular edema (DME).

Methods

We retrospectively reviewed the clinical data of 118 patients with DME admitted to The Affiliated Eye Hospital of Nanchang University from May 2021 to March 2023. Among them, 38 patients received LP alone (Laser-group), 39 patients received ranibizumab alone (Ranibizumab-group), and 41 patients received LP combined with ranibizumab (Combined-group). The improvement of macular edema (ME), visual acuity, and complications between the groups were compared.

Results

The time of ME regression, exudation absorption and fundus hemorrhage absorption in the Combined-group was shorter than in the Laser-group and the Ranibizumab-group (P<0.05). After treatment, the CMT and RNV of the three groups decreased compared to pretreatment levels and were lower in the Combined-group compared to the Laser-group and the Ranibizumab-group (P<0.05). BCVA increased after the treatment in all groups, and was markedly higher in the Combined-group than in the Laser and the Ranibizumab-groups (P<0.05). NO were higher in the Combined-group compared to the Laser-group and the Ranibizumab-group. The post-treatment VEGF levels decreased in all groups, and were significantly lower in the Combined-group compared to the Laser-group and the Ranibizumab-group (P<0.05). The incidence of complications in the Combined-group was lower than in the Laser-group and the Ranibizumab-group (P<0.05).

Conclusions

Compared to ranibizumab or LP alone, ranibizumab combined with LP is more effective in reducing ME in patients with DEM, and is associated with fewer complications.

Use of Ranibizumab for evaluating focal laser combination therapy for refractory diabetic macular edema patients: an exploratory study on the RELAND trials

Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for diabetic macular edema (DME), but is less effective in some patients. We conducted a prospective study to determine whether laser combination therapy with anti-VEGF was more effective than Ranibizumab monotherapy in anti-VEGF-resistant DME patients. There was no significant difference in the improvement of the best-corrected visual acuity (BCVA) between the laser combination therapy and Ranibizumab monotherapy groups (3.2 letters and -7.5 letters, p = 0.165). BCVA did not significantly change between visits 1 and 7 (the laser combination group, 64.3 letters 70.3 letters, respectively, p = 0.537; the Ranibizumab monotherapy group, 72.3 letters and 64.8 letters, respectively, p = 0.554), with no significant improvements in central foveal retinal thickness (the laser combination therapy group, 9.3%: the Ranibizumab monotherapy groups, - 7.3%; p = 0.926). There was no significant difference in the number of Ranibizumab intravitreal therapy (IVT) sessions between the groups (laser combination therapy, 5.2; ranibizumab monotherapy, 6.0; p = 0.237). This study did not show that laser combination therapy was significantly more effective for anti-VEGF-resistant DME than anti-VEGF monotherapy alone. Therefore, for anti-VEGF-resistant DME, alternative therapeutic approaches beyond combined laser therapy may be considered.

Role of the Vitreous in Retinal Pathology: A Narrative Review

The vitreous body is an anatomically and biochemically complex structure. Because of its proximity and firm adherence to the retina, researchers have examined the link between these two structures and how their individual pathologies might be connected. Several experimental and clinical studies have already demonstrated the important role of vitreous in the pathogenesis of retinal disorders. This narrative review highlights the role of the vitreous in retinal diseases and the improvements that have been made since the introduction of optical coherence tomography. This leads to a better understanding of vitreoretinal diseases and demonstrates its determinant role in other retinal pathologies, such as diabetic retinopathy or age-related macular degeneration. As we deepen our knowledge of the vitreous's structure, function, and abnormal conditions, we can better link the changes in diseases and identify effective treatments.