Cost-effectiveness of Intravitreal Ranibizumab With Verteporfin Photodynamic Therapy Compared With Ranibizumab Monotherapy for Patients With Polypoidal Choroidal Vasculopathy

A Nucleic Acid-Based LYTAC Plus Platform to Simultaneously Mediate Disease-Driven Protein Downregulation

Protein degradation techniques, such as proteolysis-targeting chimeras (PROTACs) and lysosome-targeting chimeras (LYTACs), have emerged as promising therapeutic strategies for the treatment of diseases. However, the efficacy of current protein degradation methods still needs to be improved to address the complex mechanisms underlying diseases. Herein, a LYTAC Plus hydrogel engineered is proposed by nucleic acid self-assembly, which integrates a gene silencing motif into a LYTAC construct to enhance its therapeutic potential. As a proof-of-concept study, vascular endothelial growth factor receptor (VEGFR)-binding peptides and mannose-6 phosphate (M6P) moieties into a self-assembled nucleic acid hydrogel are introduced, enabling its LYTAC capability. Small interference RNAs (siRNAs) is then employed that target the angiopoietin-2 (ANG-2) gene as cross-linkers for hydrogel formation, giving the final LYTAC Plus hydrogel gene silencing ability. With dual functionalities, the LYTAC Plus hydrogel demonstrated effectiveness in simultaneously reducing the levels of VEGFR-2 and ANG-2 both in vitro and in vivo, as well as in improving therapeutic outcomes in treating neovascular age-related macular degeneration in a mouse model. As a general material platform, the LYTAC Plus hydrogel may possess great potential for the treatment of various diseases and warrant further investigation.

Real-world cost-effectiveness of anti-VEGF monotherapy and combination therapy for the treatment of polypoidal choroidal vasculopathy

OBJECTIVES

For patients with polypoidal choroidal vasculopathy (PCV), intravitreal anti-vascular endothelial growth factor (anti-VEGF) combination therapy has been shown to be cost-saving relative to monotherapy in a clinical trial setting. However, whether this also applies to real-world settings is unclear. We aim to compare the real-world functional outcomes and cost-effectiveness of intravitreal anti-VEGF combination therapy relative to monotherapy, to investigate whether combination therapy is truly cost-saving.

METHODS

We used a Markov model to simulate a hypothetical cohort of PCV patients treated at Singapore National Eye Centre. Model parameters were informed by coarsened exact matched estimates of a two-year retrospective study of patients who initiated treatment in 2015. Treatment options included intravitreal aflibercept, bevacizumab, or ranibizumab, as monotherapy or in combination with full-fluence verteporfin photodynamic therapy.

RESULTS

The two-year logMAR letters gains were significant for combination therapy ( + 10.6, P = 0.006) but not monotherapy (-2.2, P = 0.459). Over 20 years, a PCV patient would cost the health system SGD 48,790 under monotherapy and SGD 61,020 under combination therapy. Quality-adjusted life-years (QALYs) were estimated to be 7.41 for monotherapy and 7.80 for combination therapy. The incremental cost-effectiveness ratio of combination therapy was SGD 31,460/QALY, which is less than the common willingness-to-pay threshold of per capita gross domestic product of Singapore (SGD 88,990/QALY). Sensitivity analysis showed that combination therapy remained incrementally cost-effective, but not cost-saving.

CONCLUSIONS

Our study shows that combination therapy is good value for money but is likely to increase costs when applied in real-world settings.

Cost-Utility Analysis of Drug Treatments in Patients with Polypoidal Choroidal Vasculopathy in Thailand

PURPOSE

The aim of this study was to estimate the cost-utility and budget impact of pharmacological treatments for the eye with polypoidal choroidal vasculopathy (PCV) in Thailand.

METHODS

A Markov model-based cost-utility analysis (CUA) and budget impact analysis were conducted. The lifetime cost and outcomes of PCV treatments were estimated. We discounted costs and outcomes at 3% per annum. Parameters were estimated using data from published literatures, local cost and utility data, and epidemiology data among Thai patients. Univariate and probabilistic sensitivity analyses were performed to account for parameter uncertainty.

RESULTS

Intravitreal bevacizumab (IVB) resulted in the lowest lifetime cost, followed by IVB plus verteporfin photodynamic therapy (IVB+vPDT) and intravitreal aflibercept (IVA). The combination of IVB or intravitreal ranibizumab (IVR) and verteporfin photodynamic therapy (IVB+vPDT or IVR+vPDT) yielded the highest quality-adjusted life-years (QALY). When compared with IVB from a societal perspective, the incremental cost-effectiveness ratio for patients with PCV receiving IVB+vPDT, IVR+vPDT, IVA were 10,304; 54,135; and 82,738 the United States dollar (USD) per QALY gained, respectively. At the Thai societal willingness to pay threshold of 4884 USD, IVB had the highest probability of being cost-effective (99%) followed by IVB+vPDT (1%). IVB+vPDT could be a cost-effective strategy and required a budget of 12.61 million USD over five fiscal years when the price of verteporfin reduced by approximately 45%.

CONCLUSION

None of the drug treatments for PCV was cost-effective in the Thai context. The decreased price of verteporfin is required to support the inclusion of IVB+vPDT in the Thai National List of Essential Medicines for the treatment of PCV.

Vitreoretinal Society of India practice pattern survey 2020: Medical retina

Purpose:

The aim of this study was to present the outcomes of the Vitreo-retinal Society of India (VRSI) Practice Pattern Survey 2020 in medical retina.

Methods:

An online survey of members of VRSI was conducted in April 2020 regarding their practice-patterns on varied medical and surgical retina topics concerning imaging and management approach. The results were evaluated by two independent experts in this field and compared with the evidence and other practice patterns in the world.

Results:

A total of 107 VRSI members participated in the online survey. Responses were obtained on management of wide-ranging chorioretinal disorders such as Central Serous Chorioretinopathy (CSCR), Polypoidal Choroidal Vasculopathy (PCV), Neovascular age related macular degeneration (n-AMD), Retinal Vein Occlusions (RVO), and Diabetic Retinopathy (DR). Participants were also surveyed regarding their attitudes and perceptions about anti-VEGF practice patterns and role of imaging in their current practice. Each of the survey question responses were then compared to contemporary literature, including evidence-based guidelines, randomized controlled trials (RCTs), real-world evidence and analogous international surveys. Comprehensive analysis related to this has been put forward in the article.

Conclusion:

This survey represents the contemporary practice patterns amongst vitreoretinal specialists in India. The survey results are vital for fellow practitioners to understand the 'standard of care’ practice in medical retina. This will guide them to devise the best possible individualized treatment strategy for most favorable clinical outcomes.

The polyp regression rate and treatment prognosis of different interventions for polypoidal choroidal vasculopathy: a systematic review and meta-analysis

PURPOSE

To estimate the polyp regression rate and treatment prognosis of different interventions for polypoidal choroidal vasculopathy (PCV) and clarify its baseline characteristics.

METHODS

The PubMed, EMBASE, and Ovid were searched up to January 2020 to identify related studies. R software version 3.6.3 was used to perform the statistical analyses. Results in proportion with 95% confidence interval (CI) were calculated by means of the Freeman-Tukey variant of arcsine square transformation. Chi-squared test and I² statistics were used to evaluate the statistical heterogeneity. Sensitivity analysis and subgroup analyses were performed to identify the source of heterogeneity.

RESULTS

This meta-analysis included 104 studies with 5816 patients. The pooling results indicated the general rate of complete polyp regression at post-treatment 12 months was 64% (95% CI [57~71%]), 89% (95% CI [81~95%]) for photodynamic therapy (PDT) monotherapy, 78% (95% CI [68~86%]) for PDT plus anti-vascular endothelial growth factor (anti-VEGF), and 42% (95% CI [35~49%]) for anti-VEGF monotherapy; PDT plus anti-VEGF showed the best efficacy in visual improvement and achieved the highest rate of dry macula (91%, 95% CI [78~99%]), while anti-VEGF monotherapy achieved the lowest polyp recurrence rate (14%, 95% CI [8~20%]); PDT monotherapy showed the best efficacy in pigment epithelial detachment regression (66%, 95% CI [58~83%]). Additionally, the baseline characteristics of PCV were also well described.

CONCLUSION

PDT plus anti-VEGF is still valuable for the management of PCV; it could achieve not only satisfactory anatomical outcomes like dry macula rate and polyp regression rate but also ideal visual prognosis like BCVA improvement.

Long-Term Outcomes of Switching from Fixed-Dose to As-Needed Regimen for Treating Submacular Hemorrhage Secondary to Polypoidal Choroidal Vasculopathy

Background: The aim of this study was to evaluate outcomes in patients with submacular hemorrhage secondary to polypoidal choroidal vasculopathy (PCV) after switching treatment from a fixed-dose to an as-needed regimen. Methods: This retrospective study included 19 patients with submacular hemorrhage secondary to PCV who were treated with fixed-dose intravitreal aflibercept during the first 56 weeks. After 56 weeks, the treatment regimen was switched to an as-needed regimen. The incidence and timing of lesion reactivation during the as-needed phase were evaluated. The best-corrected visual acuity (BCVA) at baseline (beginning of the regimen) and the final follow-up were compared. Multivariate analysis was performed to determine the factors associated with lesion reactivation. Results: During the mean follow-up period of 27 ± 7.3 months, lesion reactivation was noted in 10 patients (52.6%; mean time period: 12.2 ± 9.1 months) in the as-needed phase. Reactivations were treated with anti-vascular endothelial growth factor (VEGF) injections (mean, 4.1 ± 2.6). The mean logarithm of the minimum angle of resolution (logMAR) BCVA was 0.26 ± 0.34 at baseline and 0.31 ± 0.38 at final follow-up (p = 0.212). Deterioration of ≥0.2 logMAR BCVA was noted in two patients (10.5%). In multivariate analysis, large lesion size was closely associated with a high risk of lesion reactivation (p = 0.009). Conclusion: Visual acuity was relatively stable after switching from a fixed-dose to an as-needed regimen, with no definite visual deterioration in the majority of patients. We conclude that patients with large lesions should be carefully monitored when switching to an as-needed regimen.

Photodynamic Therapy for Chorioretinal Diseases: A Practical Approach

Photodynamic therapy (PDT) using verteporfin (Visudyne®; Bausch + Lomb) is a treatment that is widely used to elicit cell and tissue death. In ophthalmology, PDT targets choroidal vascular abnormalities and induces selective occlusion of vessels. PDT was originally used in combination with full-dose verteporfin to treat neovascular age-related macular degeneration. Since the introduction of treatment with vascular endothelial growth factor receptor inhibitors, the clinical targets of PDT have shifted to other chorioretinal conditions, such as central serous chorioretinopathy, polypoidal choroidal vasculopathy, and choroidal hemangioma. In recent years, clinical studies have facilitated the optimization of treatment outcomes through changes in protocols, including the introduction of reduced treatment settings, such as PDT with half-dose verteporfin and half-fluence PDT. Here, we review PDT and its use for chorioretinal diseases from a practical perspective.