Aflibercept versus ranibizumab for treating persistent diabetic macular oedema

Aflibercept or ranibizumab for diabetic macular edema

Background

Vascular endothelial growth factor (VEGF) is the primary substance involved in retinal barrier breach. VEGF overexpression may cause diabetic macular edema (DME). Laser photocoagulation of the macula is the standard treatment for DME; however, recently, intravitreal anti-VEGF injections have surpassed laser treatment. Our aim was to evaluate the efficacy of intravitreal injections of aflibercept or ranibizumab for managing treatment-naive DME.

Methods

This single-center, retrospective, interventional, comparative study included eyes with visual impairment due to treatment-naive DME that underwent intravitreal injection of either aflibercept 2 mg/0.05 mL or ranibizumab 0.5 mg/0.05 mL at Al-Azhar University Hospitals, Egypt between March 2023 and January 2024. Demographic data and full ophthalmological examination results at baseline and 1, 3, and 6 months post-injection were collected, including the best-corrected distance visual acuity (BCDVA) in logarithm of the minimum angle of resolution (logMAR) notation, slit-lamp biomicroscopy, dilated fundoscopy, and central subfield thickness (CST) measured using spectral-domain optical coherence tomography.

Results

Overall, the 96 eyes of 96 patients with a median (interquartile range [IQR]) age of 57 (10) (range: 20-74) years and a male-to-female ratio of 1:2.7 were allocated to one of two groups with comparable age, sex, diabetes mellitus duration, and presence of other comorbidities (all P >0.05). There was no statistically significant difference in baseline diabetic retinopathy status or DME type between groups (both P >0.05). In both groups, the median (IQR) BCDVA significantly improved from 0.7 (0.8) logMAR at baseline to 0.4 (0.1) logMAR at 6 months post-injection (both P = 0.001), with no statistically significant difference between groups at all follow-up visits (all P >0.05). The median (IQR) CST significantly decreased in the aflibercept group from 347 (166) µm at baseline to 180 (233) µm at 6 months post-injection, and it decreased in the ranibizumab group from 360 (180) µm at baseline to 190 (224) µm at 6 months post-injection (both P = 0.001), with no statistically significant differences between groups at all follow-up visits (all P >0.05). No serious adverse effects were documented in either group.

Conclusions

Ranibizumab and aflibercept were equally effective in achieving the desired anatomical and functional results in patients with treatment-naïve DME in short-term follow-up without significant differences in injection counts between both drugs. Larger prospective, randomized, double-blinded trials with longer follow-up periods are needed to confirm our preliminary results.

One-year results of switching to aflibercept for persistent diabetic macular edema resistant to bevacizumab

PURPOSE

The aim of this study is to evaluate the functional and anatomical effects of switching from bevacizumab to aflibercept in patients with persistent diabetic macular edema (DME) resistant to bevacizumab.

MATERIALS AND METHODS

Patients with DME refractory to bevacizumab (1.25 mg/0.05 mL) were subsequently switched to aflibercept. The included patients received five loading doses of intravitreal aflibercept (2 mg/0.05 mL) given monthly. After the loading dose, aflibercept was injected every 2 months. The follow-up duration was 1 year.

RESULTS

The study consisted of 37 eyes of 37 patients. The mean age of the participants was 56.81 ± 7.11 years. The mean central macular thickness at baseline was 428.32 ± 84.89 μm, which decreased significantly to 275.54 ± 50.24 μm (P < 0.003). There was a significant improvement in the mean best-corrected logMAR visual acuity from 0.627 ± 0.307 at baseline to 0.203 ± 0.235 (P < 0.017) at the end of follow-up.

CONCLUSIONS

Aflibercept is effective in patients with persistent DME not responsive to bevacizumab.

Angiopoietins as Potential Targets in Management of Retinal Disease

The Ang/Tie2 pathway complements VEGF-mediated activity in retinal vascular diseases such as DME, AMD, and RVO by decreasing vascular integrity, increasing neovascularization, and increasing inflammatory signaling. Faricimab is a bispecific antibody that has been developed as an inhibitor of both VEGF and Ang2 that has shown positive results in phase I, II and III trials. Recent Year 1 data from phase III clinical trials YOSEMITE, RHINE, TENAYA, and LUCERNE have confirmed the efficacy, safety, durability, and superiority of faricimab in patients with DME and nAMD. Faricimab, if approved, may significantly decrease treatment burden in patients with retinal vascular diseases to a greater extent than would current standard of care anti-VEGF injections.

Antiangiogenic cytokines as potential new therapeutic targets for resveratrol in diabetic retinopathy

Diabetes mellitus (DM) affects >350 million people worldwide. With many complications that can reduce the patient’s quality of life, vision loss is one of the most debilitating disorders it can cause. Active research in the field of diabetes includes microvascular complications in diabetic retinopathy (DR). Disturbances in the balance of pro-angiogenesis and anti-angiogenesis factors can lead to the progression of DR. The retinal pigment epithelium (RPE) is the outermost layer of the retina, and it is essential in maintaining the visual function. The RPE produces and secretes growth factors as well as protective agents which maintain structural integrity of the retina. Small natural molecules, such as resveratrol, may influence neurotrophic factors of the retina. The pigment epithelium-derived factor (PEDF) and thrombospondin-1 (TSP-1) are secreted by RPE cells. These two proteins inhibit angiogenesis and inflammation in RPE cells. An alteration of their production contributes to various eye diseases. There is a critical balance between two important factors secreted on opposite sides of the RPE: at the basal side, vascular endothelial growth factor (VEGF; acts on the choroidal endothelium) and, on the apical side, PEDF (acts on neurons and photoreceptors). Resveratrol inhibits VEGF expression in human adult RPE cells and limits the development of proliferative vitreoretinopathy, by attenuating transforming growth factor-β2-induced wound closure and cell migration. Possible new mechanisms could include PEDF and TSP-1 expression alterations under physiological and pathological conditions. Resveratrol is currently of interest due to its capacity to influence the cell’s secretory activity. Some limitations arise from its low bioavailability. Several drug delivery systems are currently tested, promising to improve tissue concentrations. This article reviews biological pathways involved in the pathogenesis of DR that could be influenced by resveratrol. A study of these pathways could identify new potential targets for the reduction of diabetic complications.

Switching Anti-VEGF Drugs in the Treatment of Diabetic Macular Edema

Since their introduction in the late 2000s, anti-vascular endothelial growth factor (VEGF) agents have become the first-line choice for center-involved diabetic macular edema (DME). Even with its proven effectiveness, there are still cases that do not respond satisfactorily. In those cases, a treatment option is to change to another anti-VEGF drug. In this paper, the authors review studies on switching between different anti-VEGF drugs in the treatment of persistent DME. An extensive bibliographic review was done using PubMed, Embase, and Scopus. Fourteen studies published from March 2010 to April 2017 reporting switching from anti-VEGF drugs in DME treatment were included. All reported good anatomical results after conversion; however, visual acuity outcomes showed great variability between publications. Therefore, switching to other anti-VEGFs in patients with DME not responding to previous anti-VEGF therapy may be an option, but the results are still not well-known due to a lack of randomized clinical trials. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:748-754.].

Conversion to Aflibercept After Prior Anti-VEGF Therapy for Persistent Diabetic Macular Edema

PURPOSE

To evaluate the short-term functional and anatomic outcomes of patients with persistent diabetic macular edema (DME) who were converted from bevacizumab and/or ranibizumab to aflibercept.

DESIGN

Retrospective, interventional, noncomparative, consecutive case series.

METHODS

Only eyes treated with at least 4 consecutive injections of ranibizumab/bevacizumab spaced 4-6 weeks apart prior to conversion and with at least 2 aflibercept injections afterward were considered for inclusion. Pertinent patient demographic, examination, and treatment data were extracted from clinical charts and tabulated for analysis.

RESULTS

Fifty eyes of 37 patients were included. Eyes received a mean of 13.7 bevacizumab/ranibizumab injections prior to conversion, followed by 4.1 aflibercept injections over 4.6 months of subsequent follow-up. The mean logMAR visual acuity at the pre-switch visit was 0.60 ± 0.43 (Snellen equivalent, 20/80). This improved to 0.55 ± 0.48 (Snellen equivalent, 20/70) by the second visit after conversion, corresponding to a mean logMAR change of -0.05 ± 0.22 (P = .12). The average central macular thickness from the pre-switch spectral-domain optical coherence tomography scan was 459.2 ± 139.2 μm. This significantly improved to 348.7 ± 107.8 μm by the second visit following conversion, reflecting a mean decrease of 112 ± 141 μm (P < .0001). The mean intraocular pressure (IOP) recorded at the pre-switch visit was 15.1 ± 3.3 mm Hg. At the second follow-up after converting to aflibercept, the IOP averaged 14.9 ± 3.2 mm Hg, with a mean decrease of 0.2 ± 3.0 mm Hg (P = .63).

CONCLUSIONS

Conversion to aflibercept for persistent DME resulted in significant anatomic improvements. While trends towards improved visual acuity and reduction in IOP were observed, these were not statistically significant.

Efficacy of single-dose dexamethasone implantation in patients with persistent diabetic macular edema

To investigate the efficacy of single-dose intravitreal dexamethasone implantation in the treatment of persistent diabetic macular edema (DME) unresponsive to 3 consecutive ranibizumab injections over a period of 6 months. Forty-one patients with a previous history of treatment for DME including at least three consecutive intravitreal ranibizumab injections were enrolled in this retrospective study. Main outcome measures were change in best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure from baseline to 6th month. At the baseline, the mean CMT was 572.4 ± 123.1 μm which improved to 264.2 ± 114.4, 317.7 ± 141.7, 410.6 ± 169.1, and 382.8 ± 181.5 μm at the 1st, 3rd, 5th, and 6th month, respectively (p < 0.05). The preoperative mean BCVA was 0.85 ± 0.54 logMAR units which improved to 0.76 ± 0.5 (p = 0.08), 0.69 ± 0.4 (p = 0.02), 0.74 ± 0.4 (p = 0.284), and 0.72 ± 0.3 (p = 0.489) logMAR units at the 1st, 3rd, 5th, and 6th months, respectively. Additional injections were required for 13 (31 %) eyes at 3rd month and 14 (34 %) eyes at 5th month due to recurrence of macular edema. Intravitreal dexamethasone implantation caused a significant improvement of BCVA and reduction of CMT in the patients with persistent DME that were unresponsive to 3 consecutive ranibizumab injections. However, retreatment before 6 months in the majority of the patients was needed despite the beneficial effects after the index procedure.