Impact on visual acuity and psychological outcomes of ranibizumab and subsequent treatment for diabetic macular oedema in Japan (MERCURY)

Poly (ADP-Ribose) Polymerase-1 (PARP-1) Inhibitors in Diabetic Retinopathy: An Attractive but Elusive Choice for Drug Development

Owing to its promiscuous roles, poly (ADP-ribose) polymerase-1 (PARP-1) is involved in various neurological disorders including several retinal pathologies. Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus affecting the retina. In the present review, we highlight the importance of PARP-1 participation in pathophysiology of DR and discuss promising potential inhibitors for treatment. A high glucose level enhances PARP-1 expression; PARP inhibitors have gained attention due to their potential therapeutic effects in DR. They target different checkpoints (blocking nuclear transcription factor (NF-κB) activation; oxidative stress protection, influence on vascular endothelial growth factor (VEGF) expression, impacting neovascularization). Nowadays, there are several improved clinical PARP-1 inhibitors with different allosteric effects. Combining PARP-1 inhibitors with other compounds is another promising option in DR treatments. Besides pharmacological inhibition, genetic disruption of the PARP-1 gene is another approach in PARP-1-initiated therapies. In terms of future treatments, the limitations of single-target approaches shift the focus onto combined therapies. We emphasize the importance of multi-targeted therapies, which could be effective not only in DR, but also in other ischemic conditions.

Anti-VEGF therapy for the long-term management of diabetic macular edema: a treat-to-target strategy based on macular morphology

In an aging population, the prevalence and burden of diabetes mellitus, diabetic retinopathy, and vision-threatening diabetic macular edema (DME) are only expected to rise around the world. Similarly to other complications of diabetes mellitus, DME requires long-term management. This article aims to review the current challenges associated with the long-term management of DME, opportunities to improve outcomes for patients, and to develop a treat-to-target strategy based on macular morphology. At present, intravitreal anti-vascular endothelial growth factor (VEGF) therapy is the standard of care for the management of DME; however, best-achievable vision outcomes with treatment are reliant on frequent injections and close monitoring, which are difficult to maintain in current clinical practice because of the burden this imposes on patients. Achieving and maintaining good vision with treatment are the most important factors for patients with DME. Landmark trials have shown that vision gains with anti-VEGF therapy are typically accompanied by anatomical improvements (e.g., reductions in retinal thickness); therefore, multimodal imaging measures of macular morphology are often used in patients with DME to guide real-world treatment decisions. We would like to propose a hypothetical treat-to-target algorithm to guide physicians on treatment strategies for the long-term management of DME. Alternative measures of retinal fluid (e.g., persistence, stability, location) may be stronger predictors of visual acuity in DME, although further research is required to confirm whether alternate quantifiable biomarkers such as subretinal fluid and intraretinal fluid volumes can be used as a biomarker of clinical improvement. Identifying novel biomarkers and treatments that target neuroinflammation and neurodegeneration, improving patient-physician communication around treatment adherence, and using treat-to-target measures may help to ensure that the long-term benefits of treatment are realized.

Complementary Approaches to Retinal Health Focusing on Diabetic Retinopathy

Diabetes mellitus affects carbohydrate homeostasis but also influences fat and protein metabolism. Due to ophthalmic complications, it is a leading cause of blindness worldwide. The molecular pathology reveals that nuclear factor kappa B (NFκB) has a central role in the progression of diabetic retinopathy, sharing this signaling pathway with another major retinal disorder, glaucoma. Therefore, new therapeutic approaches can be elaborated to decelerate the ever-emerging "epidemics" of diabetic retinopathy and glaucoma targeting this critical node. In our review, we emphasize the role of an improvement of lifestyle in its prevention as well as the use of phytomedicals associated with evidence-based protocols. A balanced personalized therapy requires an integrative approach to be more successful for prevention and early treatment.

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

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy.

Response to Initial Anti-Vascular Endothelial Growth Factor for Diabetic Macular Edema Is Significantly Correlated with Response to Third Consecutive Monthly Injection

Purpose: To determine whether the response to the initial anti-vascular endothelial growth factor (anti-VEGF) injection to treat diabetic macular edema (DME) is significantly correlated with the response to the third consecutive monthly injection of the same anti-VEGF agent. Methods: Seventy eyes with DME that were treated with an anti-VEGF agent (16 eyes with 1.25-mg bevacizumab, 35 eyes with 0.5-mg ranibizumab, and 19 eyes with 2.0-mg aflibercept) were studied. They were treated with three consecutive monthly injections of one of the three anti-VEGF agents. The best-corrected visual acuity (BCVA) in the logarithm of the minimum angle of resolution (logMAR units) and the central macular thickness (CMT) were measured at the baseline, 1 week after the initial injection, and 1 month after the third consecutive monthly injection. The changes of both values from the baseline 1 week after the initial injection (day 7) and 1 month after the third monthly injection were determined. The significance of the correlations between the BCVA and the CMT was determined. Results: The mean BCVA improved significantly for all three agents (0.38 ± 0.22 logMAR units at the baseline to 0.27 ± 0.25 logMAR units) after the three monthly injections (p < 0.05, repeated ANOVA). For all cases, a moderate but significant correlation was found between the BCVA at day 7 and 1 month after the third injection (r = 0.58, p < 0.01; Spearman’s rank correlation). No significant correlation was found for bevacizumab (r = 0.09, p = 0.73), moderate correlation was found for ranibizumab (r = 0.42, p < 0.05), and a strong correlation was found for aflibercept (r = 0.83, p < 0.001) between the BCVA at day 7 and at 1 month after the third injection. The mean CMT improved significantly for all three agents (481.9 ± 96.3 μm at the baseline to 364.1 ± 116.0 μm after the three monthly injections, p < 0.05), and a moderate correlation was found for the three agents between CMT at day 7 to that at one month after the third anti-VEGF injection (r = 0.54, p < 0.01). A moderate correlation was found for all three agents between CMT at day 7 to that at one month after the third anti-VEGF injection (r = 0.68 for bevacizumab, r = 0.41 for ranibizumab and r = 0.53 for aflibercept, p < 0.05). Conclusions: The significant correlations between the results on day 7 to that one month after the third anti-VEGF treatment for DME indicates that the long-term effects of anti-VEGF therapy can be predicted by the short-term response. In addition, the results indicate that there may be differences in the effectiveness between the three anti-VEGF agents.

Two-year visual and psychological outcomes of ranibizumab and subsequent treatment for diabetic macular oedema in Japan (MERCURY)

Objective

We report the 2-year visual and psychological outcomes of the MERCURY study, examining the long-term effectiveness and safety of ranibizumab and subsequent therapy in Japanese patients with diabetic macular oedema with impaired visual acuity (VA) in the real-world setting.

Methods and analysis

This was a 24-month, phase 4, open-label, single-arm, multicentre, prospective, observational study. Following an initial dose of ranibizumab (0.5 mg) by intravitreal injection (0.05 mL), treatment was administered as needed after month 1. The primary treated eye (PTE) was the first eye that received a ranibizumab injection.

Results

In total, 209 patients were enrolled; 192 (91.9%) and 174 (83.3%) completed months 12 and 24, respectively. In the PTE set, mean±SD changes in best-corrected VA (BCVA) from baseline to months 12 (primary endpoint) and 24 were −0.08±0.35 (p=0.015) and −0.13±0.30 (p<0.001) logarithmic minimum angle of resolution, respectively. Mean±SD central subfoveal thickness (CSFT) changes from baseline to months 12 and 24 were −102.3±146.1 µm (p<0.001) and −103.6±157.2 µm (p<0.001), respectively. Patients receiving three injections during the first 2 months had greater BCVA improvements throughout the study than those receiving 1–2 consecutive injections. Overall, 91 (43.5%) and 130 (62.2%) patients had ocular and non-ocular adverse events, respectively. At month 24, the mean±SD Hospital Anxiety and Depression Scale (HADS)-Anxiety and HADS-Depression scores decreased by 0.44±3.75 (p=0.196) and 0.19±3.38 (p=0.541), respectively.

Conclusions

At 24 months after initiation of ranibizumab and subsequent treatment, patients showed significant BCVA and CSFT improvements. Long-term treatment was considered safe and tolerable and did not lead to worsened psychological status.

Progress of Diabetic Macular Edema after Loading Injection of Anti-Vascular Endothelial Growth Factor Agents in Real-World Cases

Background and Objectives: To evaluate the recurrence of diabetic macular edema (DME) after loading an injection of anti-VEGF agents by a pro re nata (PRN) protocol using central retinal thickness (CRT) as a re-injection criterion. Materials and Methods: This is a retrospective, observational single-center study. DME patients with a central retinal thickness (CRT) over 350 μm received a PRN injection of anti-VEGF agents following one to three consecutive monthly loading injections (bevacizumab, ranibizumab, and aflibercept) for 6 months from January 2012 to June 2019. Results: We enrolled a total of 72 eyes for loading injections and the mean CRT improved from 434.04 ± 139.4 μm (before treatment) to 362.9 ± 125.0 μm after the loading injection. One week after injection, 36 eyes (50%) obtained a CRT of ≤350 μm. Fourteen eyes (19.4%) remained with a CRT of ≤350 μm for 6 months without additional injections. A total of 22 eyes (30.6%) had a CRT of >350 μm at 6 months. Fifteen eyes did not receive additional injections because of visual improvement. Conclusions: About 20% of DME patients can be maintained at a CRT of ≤350 μm for 6 months with only a loading injection. However, there is a tendency to delay additional injections for patients with recurrences using PRN protocol.

Anti-vascular endothelial growth factor therapy in diabetic macular edema: real-life outcomes from a multicenter study in Turkey over 36 months

PURPOSE

This study aimed to report the visual and anatomical outcomes of intravitreal anti-VEGF treatment for diabetic macular edema (DME) in a real-world clinical setting from Turkey over 36 months.

METHODS

This is a retrospective, multicenter (7 sites) study. The medical records of 1072 eyes (both previously treated and naive eyes) of 706 consecutive patients with visual impairment due to center-involving DME treated with intravitreal anti-VEGF injections between April 2007 and February 2017 were reviewed. The eyes were divided into mutually exclusive three groups based on the duration of follow-up (12, 24, or 36 months). Primary outcome measures were changes in visual acuity (VA) and central macular thickness (CMT) from baseline to final visit in each cohort, frequency of visits and intravitreal anti-VEGF injections. As secondary endpoints, VA outcomes were assessed in subgroups stratified by baseline VA [<70 ETDRS letters and ≥70 ETDRS letters] and loading dose status of anti-VEGF injections.

RESULTS

VA increased by a mean of 8.2 letters (12-month cohort, p < 0.001), 5.3 letters (24-month cohort, p < 0.001), and 4.4 letters (36-month cohort, p = 0.017) at final visits. The eyes with <70 VA letters achieved more significant VA improvement at final visits in all cohorts compared with eyes with >70 VA letters (p < 0.001). The mean decreases in CMT from baseline to last visits at 12-, 24-, and 36- month cohorts were -100.5 µm, -107.7 µm, and -114.3 µm, respectively (p < 0.001). The mean number of injections given were 4.6, 2.3, and 1.8 during years 1 to 3, respectively. Patients who received loading dose showed greater VA gains than those who did not in all follow-up cohorts.

CONCLUSION

Our study revealed that anti-VEGF treatment improved VA and CMT over a follow-up of 36 months. Although these real-life VA outcomes following anti-VEGF therapy for DME were similar to other real-life studies, they were inferior to those noted in randomized controlled trials, mainly due to undertreatment.

The Impact of Interval between Recurrence and Reinjection in Anti-VEGF Therapy for Diabetic Macular Edema in Pro Re Nata Regimen

Background: Pro re nata (PRN) regimen using anti-vascular endothelial growth factor (VEGF) agent is popular for the treatment of diabetic macular edema (DME). We investigated the influence of waiting time (WT) and interval between the date of recurrence of edema and re-injection on treatment efficacy. Methods: This retrospective study conducted at 7 sites in Japan enrolled patients who received intravitreal injection of ranibizumab (IVR) and aflibercept (IVA) in 1+PRN regimen. Enrolled patients were divided into 2 groups: prompt group (less than 1 week) and deferred group (3 weeks or more). Central retinal thickness (CRT) and best corrected visual acuity (BCVA) were measured every month for 1 year. Results: CRT in the deferred group was significantly higher than that in the prompt group at 2, 5, 6, 7, and 12 months (p < 0.05). BCVA in the prompt group was significantly better than that in the deferred group at 7, 10, and 12 months (p < 0.05). Conclusion: The prompt group was superior in anatomical and functional improvement of DME in anti-VEGF therapy than the deferred group. Our data suggests that shorter WT is recommended for better visual prognosis in the treatment for DME.