Emerging pharmacotherapies for diabetic macular edema

Review of real-world evidence of dual inhibition of VEGF-A and ANG-2 with faricimab in NAMD and DME

Management of vitreoretinal disorders (e.g., neovascular age-related macular degeneration [nAMD] and diabetic macular edema [DME]) have assumed the standard therapy of lifelong anti-VEGF injections with drugs like aflibercept, brolucizumab, ranibizumab and bevacizumab. However, the burden imposed on patients is a major deterrent for continual therapy and recovery. Faricimab, a bispecific antibody, blocking both VEGF-A and Ang-2 molecules, produces a comparable functional and anatomical results, with less injections, significantly reducing patient burden. Visual acuity, safety, adverse effects, and anatomical outcomes are discussed in the pivotal clinical trials (YOSEMITE/RHINE and TENAYA/LUCERNE), and early data from real-world studies (TRUCKEE, TAHOE, FARWIDE-DME, FARETINA and others). In YOSEMITE and RHINE, faricimab demonstrated non-inferior vision gains, better anatomical outcomes compared to aflibercept every 8 weeks. Faricimab in the personalized treatment interval (PTI), after week 96, achieved 12-week interval in 78.1% of the patients and 16-week interval in 62.3%. TENAYA and LUCERNE reported comparable best corrected visual acuity (BCVA) improvement and better anatomic outcomes during head-to-head phase, parallel to aflibercept, at its 8-week treatment schedule. Faricimab in the PTI regimen, after week 96 achieved 12-week interval in 77.8% of the patients and 16-week interval in 63.1%. Safety of faricimab has been comparable to aflibercept in these pivotal trials. Real-world data supports the data from the pivotal studies regarding the efficacy and safety profile of faricimab in heterogenous real world patient population. Moreover, in previously treated patients, it also demonstrated a faster fluid resolution, good safety profile. Considering faricimab has demonstrated anatomic and durability benefit in the treatment of nAMD and DME, additional data from ongoing extension clinical trials, AVONELLE-X and RHONE-X will help understand longer term outcomes for patients treated with faricimab as well as patients switching from aflibercept to faricimab after finishing the pivotal trials. Longer term data from the real-world studies will also continue to contribute to our understanding of long-term efficacy, safety and durability in the real world patient population.

Lp-PLA2 activity is associated with increased risk of diabetic retinopathy: a longitudinal disease progression study

AIMS/HYPOTHESIS

The aim of the study was to examine the association between lipoprotein-associated phospholipase A2 (Lp-PLA2) activity levels and incident diabetic retinopathy and change in retinopathy grade.

METHODS

This was a cohort study of diabetic participants with serum collected at baseline and routinely collected diabetic retinal screening data. Participants with type 2 diabetes from the GoDARTS (Genetics of Diabetes Audit and Research in Tayside Scotland) cohort were used. This cohort is composed of individuals of white Scottish ancestry from the Tayside region of Scotland. Survival analysis accounting for informative censoring by modelling death as a competing risk was performed for the development of incident diabetic retinopathy from a disease-free state in a 3 year follow-up period (n = 1364) by stratified Lp-PLA2 activity levels (in quartiles). The same analysis was performed for transitions to more severe grades.

RESULTS

The hazard of developing incident diabetic retinopathy was 2.08 times higher (95% CI 1.64, 2.63) for the highest quartile of Lp-PLA2 activity compared with the lowest. Higher Lp-PLA2 activity levels were associated with a significantly increased risk for transitions to all grades. The hazards of developing observable (or more severe) and referable (or more severe) retinopathy were 2.82 (95% CI 1.71, 4.65) and 1.87 (95% CI 1.26, 2.77) times higher for the highest quartile of Lp-PLA2 activity compared with the lowest, respectively.

CONCLUSIONS/INTERPRETATION

Higher Lp-PLA2 levels are associated with increased risk of death and the development of incident diabetic retinopathy, as well as transitions to more severe grades of diabetic retinopathy. These associations are independent of calculated LDL-cholesterol and other traditional risk factors. Further, this biomarker study shows that the association is temporally sensitive to the proximity of the event to measurement of Lp-PLA2.

Pharmacotherapy for diabetic retinopathy

BACKGROUND

Diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) continue to cause significant visual loss among patients with diabetes mellitus. In some patients unresponsive to standard laser techniques, as well as improved control of blood pressure and blood sugar, pharmacologic treatment may be beneficial. Although no agent is now approved by the FDA for this purpose, many agents are now being studied in randomized clinical trials (RCTs).

OBJECTIVE

To review concisely the chief pharmacotherapies for diabetic retinopathy available at present.

METHODS

Literature review and synopsis.

RESULTS

Used alone, intravitreal triamcinolone acetonide (IVTA) seems to have some short-term efficacy against DME, but longer-term outcomes (< or = 3 years) using IVTA monotherapy showed a lesser benefit than focal/grid laser treatment in a prospective RCT done by the Diabetic Retinopathy Clinical Research Network. Intravitreal anti-VEGF agents have demonstrated some short-term efficacy against DME, and continuing RCTs will evaluate combination therapies (anti-VEGF and laser) for both DME and PDR. Other agents are being evaluated in pilot studies and Phase II RCTs.

CONCLUSION

Pharmacotherapies for DME and PDR have potential for vision stabilization or improvement. Continuing RCTs will provide evidence-based data on their role in clinical practice. A potential role for pharmacotherapy in the prevention of DME and PDR is also emerging.

Primary treatment of diabetic macular edema

Diabetic macular edema (DME) is a leading cause of vision loss in older Americans. Thermal laser treatment remains the mainstay of treatment for DME. Recently, alternative primary treatments for DME have been evaluated. These treatments include intravitreal injections of steroids as well as pharmaceuticals containing antibodies against vascular endothelial growth factor (VEGF). Surgical treatment has been shown to be appropriate in selected cases. We review the evidence and scientific rationale for various primary treatment options in patients with DME. Regular and timely ophthalmologic evaluation remains crucial to recognition and treatment of macular edema in diabetic patients.

Eye disease and the older diabetic

Elderly diabetic persons are 1.5 times more likely than age-matched nondiabetic persons to develop vision loss and blindness. Annually, between 12,000 and 24,000 diabetic patients in the United States become legally blind because of complications caused by diabetic retinopathy. Even more diabetic persons experience vision loss caused by comorbid ocular and periocular conditions such as dry eye syndrome, cataracts, macular degeneration, and glaucoma. This article discusses the synergy between these conditions and diabetes. Standards of care that slow the progression of vision loss and exciting new research on new strategies of care that may reverse vision loss are presented.