Future of anti-VEGF: biosimilars and biobetters

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.

Sustained and Efficient Delivery of Antivascular Endothelial Growth Factor by the Adeno-associated Virus for the Treatment of Corneal Neovascularization: An Outlook for Its Clinical Translation

Corneal diseases represent 5.1% of all eye defects and are the fourth leading cause of blindness globally. Corneal neovascularization can arise from all conditions of chronic irritation or hypoxia, which disrupts the immune-privileged state of the healthy cornea, increases the risk of rejection after keratoplasty, and leads to opacity. In the past decades, significant progress has been made for neovascular diseases of the retina and choroid, with plenty of drugs getting commercialized. In addition, to overcome the barriers of the short duration and inadequate penetration of conventional formulations of antivascular endothelial growth factor (VEGF), multiple novel drug delivery systems, including adeno-associated virus (AAV)-mediated transfer have gone through the full process of bench-to-bedside translation. Like retina neovascular diseases, corneal neovascularization also suffers from chronicity and a high risk of recurrence, necessitating sustained and efficient delivery across the epithelial barrier to reach deep layers of the corneal stroma. Among the explored methods, adeno-associated virus-mediated delivery of anti-VEGF to treat corneal neovascularization is the most extensively researched and most promising strategy for clinical translation although currently although, it remains predominantly at the preclinical stage. This review comprehensively examines the necessity, benefits, and risks of applying AAV vectors for anti-VEGF drug delivery in corneal vascularization, including its current progress and challenges in clinical translation.

Off-Label Use of Bevacizumab in Patients Diagnosed with Age-Related Macular Degeneration: A Systematic Review and Meta-Analysis

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of vision loss in elderly people. Current pharmacological treatment in vascular AMD includes anti-VEGF agents, such as ranibizumab and aflibercept. Additionally, the off-label use of bevacizumab has been shown to be effective and has a lower cost, making it an interesting pharmacological approach; however, there is no consensus about its use. Therefore, this systematic review and meta-analysis aims to evaluate the efficacy, safety, and efficiency of bevacizumab in AMD patients.

METHODS

This review only focused on randomized controlled clinical trials published in 2010 in the MEDLINE database that compared the effect of bevacizumab with ranibizumab. The risk of bias in each included study was assessed using the CASP Randomised Clinical Trials checklist.

RESULTS

Twelve studies were included for qualitative synthesis, and nine of them were considered for meta-analysis. Bevacizumab-treated patients showed a significantly reduced neovascularization in a longer spectrum of time; however, they had a higher incidence of endophthalmitis than those treated with ranibizumab. Regarding efficiency, the mean number of administrations was reduced in the treatment with bevacizumab in comparison to ranibizumab.

CONCLUSIONS

Clinical evidence demonstrates that bevacizumab has efficacy and safety profiles comparable with ranibizumab; however, it is relatively more efficient.

Efficacy, safety, and cost-effectiveness of biosimilars of bevacizumab in näive patients with diabetic macular edema

OBJECTIVES

Anti-vascular endothelial growth factor (VEGF) therapy restores retinal architecture and enhances vision in diabetic macular edema (DME). Bevacizumab is an off-label anti-VEGF drug that effectively treats DME. The safety and efficacy of bevacizumab biosimilars, which are more affordable than the original medication, still need to be established. This study aimed to assess the cost-effectiveness, efficacy, and safety of biosimilars for treating patients with naïve DME across various price ranges that are accessible in the Indian market.

MATERIALS AND METHODS

Two biosimilars, BevaciRelTM (Reliance Life Sciences Pvt. Ltd.) and ZyBev (Cadila Healthcare Limited), were compared to their original, Avastin (Roche Products [India] Pvt. Ltd.), in a randomized, control study. Three end-notes were used to assess safety and efficacy: persistence, improvement, and adverse events. Cost-effective analysis was carried out using a decision-tree analysis model.

RESULTS

This study included 69 (59%) men and 54 (41%) women with naïve DME. The cohort had an average log MAR visual acuity of 0.87 ± 0.22, and the central retinal thickness at baseline on OCT was 398.5 ± 37.61 μm. The visual acuity showed a similar improvement, and there was a decrease in central retinal thickness as observed on OCT across the groups. The incremental cost-effectiveness ratio was 10.8.

CONCLUSIONS

The biosimilars of bevacizumab are safe and efficacious in treating DME in a cost-effective manner.

Biosimilars of anti-vascular endothelial growth factor for ophthalmic diseases: A review

The development of intravitreally injected biologic medicines (biologics) acting against vascular endothelial growth factor (VEGF) substantially improved the clinical outcomes of patients with common VEGF-driven retinal diseases. The relatively high cost of branded agents, however, represents a financial burden for most healthcare systems and patients, likely resulting in impaired access to treatment and poorer clinical outcomes for some patients. Biosimilar medicines (biosimilars) are clinically equivalent, potentially economic alternatives to reference products. Biosimilars approved by leading health authorities have been demonstrated to be similar to the reference product in a comprehensive comparability exercise, generating the totality of evidence necessary to support analytical, pre-clinical, and clinical biosimilarity. Anti-VEGF biosimilars have been entering the field of ophthalmology in the US since 2022. We review regulatory and scientific concepts of biosimilars, the biosimilar development landscape in ophthalmology, with a specific focus on anti-VEGF biosimilars, and discuss opportunities and challenges facing the uptake of biosimilars.

Biosimilar Candidate CT-P42 in Diabetic Macular Edema: 24-Week Results from a Randomized, Active-Controlled, Phase III Study

OBJECTIVE

To demonstrate the therapeutic similarity of CT-P42 compared with reference aflibercept (Eylea) in adult patients with diabetic macular edema (DME).

DESIGN

Randomized, active-controlled, double-masked, phase III clinical trial PARTICIPANTS: Patients with a diagnosis of either type 1 or 2 diabetes mellitus with DME involving the center of the macula.

METHODS

Patients were randomized (1:1) to receive either CT-P42 or reference aflibercept (2 mg/0.05 ml) by intravitreal injection every 4 weeks (5 doses), then every 8 weeks (4 doses), in the main study period. Results up to week 24 are reported herein.

MAIN OUTCOME MEASURES

The primary end point was mean change from baseline at week 8 in best-corrected visual acuity (BCVA) using the ETDRS chart. Equivalence between CT-P42 and reference aflibercept was to be concluded if the 2-sided 95% confidence interval (CI) (global assumptions) and 2-sided 90% CI (United States Food and Drug Administration [FDA] assumptions) for the treatment difference fell entirely within the equivalence margin of ±3 letters, as assessed in the full analysis set.

RESULTS

Overall, 348 patients were randomized (CT-P42: 173; reference aflibercept: 175). Best-corrected visual acuity improved from baseline to week 8 in both groups, with a least squares mean (standard error) improvement of 9.43 (0.798) and 8.85 (0.775) letters in the CT-P42 and reference aflibercept groups, respectively. The estimated between-group treatment difference was 0.58 letters, with the CIs within the predefined equivalence margin of ±3 letters (95% CI, -0.73 to 1.88 [global]; 90% CI, -0.52 to 1.67 [FDA]). Through week 24, other efficacy results for the 2 groups, in terms of change in BCVA and retinal central subfield thickness, as well as ETDRS Diabetic Retinopathy Severity Scale score, supported therapeutic similarity. Pharmacokinetics, usability, safety (including the proportions of patients experiencing ≥1 treatment-emergent adverse event [CT-P42: 50.3%; reference aflibercept: 53.7%]), and immunogenicity were also comparable between groups.

CONCLUSIONS

This study in patients with DME demonstrated equivalence between CT-P42 and reference aflibercept (2 mg/0.05 ml) in terms of efficacy, with similar pharmacokinetic, usability, safety, and immunogenicity profiles.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Comparison of the efficacy and safety of SCD411 and reference aflibercept in patients with neovascular age-related macular degeneration

To compare the efficacy and safety of the proposed aflibercept biosimilar SCD411 and reference aflibercept in patients with neovascular age-related macular degeneration, this randomized, double-masked, parallel-group, multicenter study was conducted in 14 countries from 13 August 2020 to 8 September 2022. Patients with neovascular age-related macular degeneration. With subfoveal, juxtafoveal, or extrafoveal choroidal neovascularization were aged 50 years or older. Intravitreal injection of SCD411 or aflibercept (2.0 mg) were administered every 4 weeks for the first three injections and every 8 weeks until week 48. The primary efficacy endpoint was the change in best-corrected visual acuity from baseline to week 8 with an adjusted equivalence margin of ± 3.0 letters. Patients were randomly assigned to receive either SCD411 (n = 288) or reference aflibercept (n = 288). A total of 566 participants (98.3%) completed week 8 of the study. The least-squares mean difference of change in best-corrected visual acuity from baseline to week 8 (SCD411-aflibercept) was - 0.4 letters (90% confidence interval =  - 1.6 to 0.9). The incidence of ocular (69 of 287 [24.0%] vs. 71 of 286 [24.8%]) and serious ocular (5 of 287 [1.7%] vs. 3 of 286 [1.0%]) treatment-emergent adverse effects were similar between the SCD411 and aflibercept groups. Immunogenicity analysis revealed a low incidence of neutralizing antibody formation in both groups. In conclusion, SCD411 has equivalent efficacy compared with reference aflibercept in patients with neovascular age-related macular degeneration and has a comparable safety profile. The results support the potential use of SCD411 for the treatment of neovascular age-related macular degeneration.

International Classification System for Ocular Complications of Anti-VEGF Agents in Clinical Trials

PURPOSE

Complications associated with intravitreal anti-VEGF therapies are reported inconsistently in the literature, thus limiting an accurate evaluation and comparison of safety between studies. This study aimed to develop a standardized classification system for anti-VEGF ocular complications using the Delphi consensus process.

DESIGN

Systematic review and Delphi consensus process.

PARTICIPANTS

Twenty-five international retinal specialists participated in the Delphi consensus survey.

METHODS

A systematic literature search was conducted to identify complications of intravitreal anti-VEGF agent administration based on randomized controlled trials (RCTs) of anti-VEGF therapy. A comprehensive list of complications was derived from these studies, and this list was subjected to iterative Delphi consensus surveys involving international retinal specialists who voted on inclusion, exclusion, rephrasing, and addition of complications. Furthermore, surveys determined specifiers for the selected complications. This iterative process helped to refine the final classification system.

MAIN OUTCOME MEASURES

The proportion of retinal specialists who choose to include or exclude complications associated with anti-VEGF administration.

RESULTS

After screening 18 229 articles, 130 complications were categorized from 145 included RCTs. Participant consensus via the Delphi method resulted in the inclusion of 91 complications (70%) after 3 rounds. After incorporating further modifications made based on participant suggestions, such as rewording certain phrases and combining similar terms, 24 redundant complications were removed, leaving a total of 67 complications (52%) in the final list. A total of 14 complications (11%) met exclusion thresholds and were eliminated by participants across both rounds. All other remaining complications not meeting inclusion or exclusion thresholds also were excluded from the final classification system after the Delphi process terminated. In addition, 47 of 75 proposed complication specifiers (63%) were included based on participant agreement.

CONCLUSIONS

Using the Delphi consensus process, a comprehensive, standardized classification system consisting of 67 ocular complications and 47 unique specifiers was established for intravitreal anti-VEGF agents in clinical trials. The adoption of this system in future trials could improve consistency and quality of adverse event reporting, potentially facilitating more accurate risk-benefit analyses.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Challenges and opportunities of developing small-molecule therapies for age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of vision loss in senior adults. The disease can be categorized into two types: wet AMD and dry AMD. Wet AMD, also known as exudative or neovascular AMD, is less common but more severe than dry AMD and is responsible for 90% of the visual impairment caused by AMD and affects 20 million people worldwide. Current treatment options mainly involve biologics that inhibit the vascular endothelial growth factor or complement pathways. However, these treatments have limitations such as high cost, injection-related risks, and limited efficacy. Therefore, new therapeutic targets and strategies have been explored to improve the outcomes of patients with AMD. A promising approach is the use of small-molecule drugs that modulate different factors involved in AMD pathogenesis, such as tyrosine kinases and integrins. Small-molecule drugs offer advantages, such as oral administration, low cost, good penetration, and increased specificity for the treatment of wet and dry AMD. This review summarizes the current status and prospects of small-molecule drugs for the treatment of wet AMD. These advances are expected to support the development of effective and targeted treatments for patients with AMD.

Gene therapy for age-related macular degeneration: potential, feasibility, and pitfalls

PURPOSE OF REVIEW

The landscape for age-related macular degeneration (AMD) is rapidly changing with addition of biosimilars and now United States Food and Drug Administration (FDA) approved nonneovascular AMD (nnAMD) treatment options. These developments have inspired a burgeoning pipeline of gene therapy approaches focused on similar antivascular endothelial growth factors (VEGF) and complement related pathways. Historic and more recent setbacks in the gene therapy pipeline, including intraocular inflammatory reactions, have raised important concerns for adverse events related to AMD therapeutics both for gene and nongene approaches. The specific clinical profile of these therapeutics approaching later stage clinical trials are complex and under active investigation; however, these options hold promise to disrupt the current landscape and change management paradigms for one of the leading causes of vision loss worldwide.

RECENT FINDINGS

This review covers current gene therapy approaches for neovascular AMD (nAMD) and nnAMD. Intravitreal, suprachoroidal, and subretinal delivery routes are discussed with attention to technical procedure, capabilities for transgene delivery to target tissue, immunogenicity, and collateral effects. Suprachoroidal delivery is an emerging approach which may bridge some of the practical drawbacks for intravitreal and subretinal methods, though with less elaborated immunologic profile. In parallel to delivery modification, viral vectors have been cultivated to target specific cells, with promising enhancements in adeno-associated viral (AAV) vectors and persistent interest in alternate viral and nonviral delivery vectors. Ongoing questions such as steroid or immunosuppressive regimen and economic considerations from a payer and societal perspective are discussed.

SUMMARY

The present review discusses emerging gene therapy options which could foster new, more durable nAMD and nnAMD therapeutics. These options will need refinement with regards to route, vector, and dosage, and specialists must decipher the specific clinical risk benefit profile for individual patients. Ongoing concerns for immunogenicity or dosage related adverse events could stifle progress, while further vector development and refined delivery techniques have the potential to change the safety and efficacy of currently options in the pipeline.

[Frequency and distribution of the active agent of intravitreal injections in German centers 2015-2021-An oregis study]

INTRODUCTION

Digitalization in medicine, especially the electronic documentation of patient data, is revolutionizing healthcare systems worldwide. The evaluation of real-world data collected under everyday conditions presents opportunities but also challenges. Electronic medical registries provide a means to compile extensive patient data for scientific inquiries. Oregis is the first nationwide digital registry for health services research established by the German Ophthalmological Society (DOG). Intravitreal operative medicinal injections (IVOM) are among the most frequently performed procedures in ophthalmology. Data on injection numbers and injection frequencies with anti-vascular endothelial growth factor (VEGF) are already available from other countries, whereas data at a national level are not yet available in Germany due to the lack of a nationwide register. It is known that the treatment success of anti-VEGF IVOMs depends largely on the adherence to treatment and thus on the number of injections. There are also differences in cost. In the context of this study, real-world data on the frequency and distribution of intravitreal injections in German centers from 2015 to 2021 were compiled for the first time since the introduction of oregis. The aim of this study is to collect data on the use of anti-VEGF IVOMs in Germany from oregis for the first time and to show the development of injection numbers and anti-VEGF drugs used. At the same time, the possibilities of data retrieval from oregis are demonstrated using a concrete example from daily ophthalmological practice.

MATERIAL AND METHODS

An automated query of records was performed for all patients who received IVOM at oregis-affiliated healthcare facilities between 2015 and 2021. The number of treated patients and the use of anti-VEGF medications, including aflibercept, bevacizumab, brolucizumab, and ranibizumab, were determined. The data were collected in a pseudonymized and anonymized manner.

RESULTS

At the time of data collection, 9 German ophthalmological healthcare facilities were affiliated with oregis. In total, 309,152 patients were registered during the observation period, with 8474 receiving IVOMs. Over the observation period, the number of participating centers, patients, and intravitreal injections increased. The proportional share of anti-VEGF agents among the total number of injections varied during the observation period.

DISCUSSION

Real-world data captured in oregis offer significant potential for enhancing healthcare provision. Oregis enables the depiction of ophthalmological care conditions in Germany and contributes to research and quality assurance. The ability to query the presented data exemplifies the multitude of inquiries through which oregis can contribute to the representation of ophthalmological care in Germany.

An Overview of Biosimilars-Development, Quality, Regulatory Issues, and Management in Healthcare

Biological therapies have transformed high-burden treatments. As the patent and exclusivity period for biological medicines draws to a close, there is a possibility for the development and authorization of biosimilars. These products boast comparable levels of safety, quality, and effectiveness to their precursor reference products. Biosimilars, although similar to reference products, are not identical copies and should not be considered generic substitutes for the original. Their development and evaluation involve a rigorous step-by-step process that includes analytical, functional, and nonclinical evaluations and clinical trials. Clinical studies conducted for biosimilars aim to establish similar efficacy, safety, and immunogenicity, rather than demonstrating a clinical benefit, as with the reference product. However, although the current knowledge regarding biosimilars has significantly increased, several controversies and misconceptions still exist regarding their immunogenicity, extrapolation, interchangeability, substitution, and nomenclature. The development of biosimilars stimulates market competition, contributes toward healthcare sustainability, and allows for greater patient access. However, maximizing the benefits of biosimilars requires cooperation between regulators and developers to ensure that patients can benefit quickly from access to these new therapeutic alternatives while maintaining high standards of quality, safety, and efficacy. Recognizing the inherent complexities of comprehending biosimilars fully, it is essential to focus on realistic approaches, such as fostering open communication between healthcare providers and patients, encouraging informed decision-making, and minimizing risks. This review addresses the regulatory and manufacturing requirements for biosimilars and provides clinicians with relevant insights for informed prescribing.

Bibliometric and visualized analysis of diabetic macular edema

PURPOSE

Our aim was to identify recent research trends on diabetic macular edema (DME) and focus on publications from different countries, institutions, and authors.

METHODS

We retrieved and analyzed data from January 1, 2003 to December 31, 2022 on the DME research field from the Web of Science Core Collection (WoSCC) database. Microsoft Excel and VOSviewer were applied to perform visualization analysis and evaluate the trends.

RESULTS

A total of 4482 publications were identified, and the annual global publications increased steadily, from 36 to 390, during this period. The United States (1339 publications, 71,754 citations), Johns Hopkins University (176 publications, 17,015 citations), and Bressler NM (76 publications, 9621 citations) were the most influential and productive countries, institutions, and authors, respectively. The top 100 keywords were classified into five clusters: (1) therapy and adverse effects of DME; (2) clinical biomarkers of DME; (3) mechanistic research on DME; (4) improving bioavailability and efficacy; and (5) early diagnosis of diabetic complications. "Diabetic macular edema," "retinopathy," "ranibizumab," and "optical coherence tomography angiography" were the most frequent keywords. Regarding the average appearing years (AAYs) of the keywords, "deep learning" (AAY:2020.83), "optical coherence tomography angiography" (AAY:2019.59), "intravitreal Aflibercept" (AAY:2019.29), and "dexamethasone implant" (AAY:2019.20) were recognized as the hotspots of the DME research area in the short run.

CONCLUSION

In the past two decades, the United States was in master status in DME research. Although intravitreal drug injection has been the mainstream therapy for a long time, the effectiveness of different drugs, such as dexamethasone, new solutions for drug delivery, such as intravitreal implantation, and more accurate tools for the classification and follow-up of DME patients, such as deep learning systems, are still research hotspots.

The Biosimilar Paradox: How Anti-Vascular Endothelial Growth Factor Biosimilars Could Increase Patient and Overall Health Care Costs

PURPOSE

Anti-vascular endothelial growth factor (VEGF) medications for intraocular use are a major and increasing cost, and biosimilars may be a means of reducing the high cost of many biologic medications. However, a bevacizumab biosimilar, which is currently pending Food and Drug Administration (FDA) approval (bevacizumab-vikg), paradoxically may increase the cost burden of intravitreal anti-VEGF agents, because off-label repackaged drugs may no longer be allowed per the Drug Quality and Security Act (DQSA). We aimed to investigate the potential impact of biosimilars on costs in the United States.

DESIGN

Cost analysis of anti-VEGF medications.

PARTICIPANTS

Medicare data from October 2022 and previously published market share data from 2019.

METHODS

Average sales prices (ASPs) of ranibizumab, aflibercept, and bevacizumab were calculated from Medicare allowable payments. The ASPs of biosimilars were calculated from wholesale acquisition costs from a representative distributor. The cost of an intraocular bevacizumab formulation is modeled at $500/1.25-mg dose and $900/1.25-mg dose.

MAIN OUTCOME MEASURES

Costs of anti-VEGF drugs to Medicare Part B and patients.

RESULTS

If an intraocular bevacizumab biosimilar were to be priced at $500, costs to Medicare would increase by $457 million from $3.01 billion to $3.47 billion (15.2% increase). Patient responsibility would increase by $117 million from $768 million to $884 million. Similarly, if intraocular bevacizumab were priced at $900, Medicare costs would increase by $897 million to $3.91 billion (29.8% increase), and patient responsibility would increase by $229 million to $997 million. If bevacizumab were $500/dose, switching all patients currently receiving ranibizumab or aflibercept to respective biosimilars would compensate for only 28.8% of the increased cost. Current prices of ranibizumab and aflibercept biosimilars would have to decrease by an aggregate of 15.7% to $616.80/injection, $1027.97/injection, and $1436.88/injection for ranibizumab 0.3 mg, ranibizumab 0.5 mg, and aflibercept, respectively.

CONCLUSIONS

An FDA-approved bevacizumab biosimilar for ophthalmic use could increase costs to the health care system and patients, raising concerns for access. This increase would not be offset by ranibizumab and aflibercept biosimilar use at current prices. These data support the need for an exemption of section 503B of the DQSA and continued use of repackaged off-label bevacizumab.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Assessment of structural and functional similarity of biosimilar products: Bevacizumab as a case study

The antiangiogenic drug bevacizumab is a blockbuster therapeutic pharmaceutical product that is used to treat many different types of cancer including kidney, colon, rectum, lung, and breast cancer. As a result, multiple biosimilars have been approved across the various regulatory jurisdictions in India (>20 in number till date). The rapidly growing market and acceptance of biosimilars was the motivation to perform comparability study of bevacizumab biosimilars that are presently available in the Indian market. A comprehensive analytical and functional biosimilarity assessment has been performed to examine and compare innovator product of bevacizumab (Avastin-innovator product, Roche Products (India) Pvt Ltd) and six biosimilars that are being marketed in India (Abevmy from Mylan Pharmaceuticals Pvt Ltd, Bevazza from Lupin Ltd, Bryxta from Zydus Cadila, Krabeva from Biocon, Ivzumab from RPG Life Sciences Ltd, and Advamab from Alkem Laboratories Ltd). Physiochemical characterization of drug products was performed with respect to their primary structure (intact mass, reduced mass, peptide mapping by LC-MS), higher order structure (secondary structure by FTIR, Far-UV-CD, and tertiary structure by Near-UV-CD, intrinsic fluorescence spectroscopy), impurity profile (SE-HPLC, SEC-MALS, extrinsic fluorescence: size heterogenicity, degradation, stability; DLS: hydrodynamic radius; WCX-HPLC: charge variants analysis) and post-translational modifications by measuring reduced glycans through fluorescence dye analysis. Functional characterization was performed by SPR and cell proliferation assay. Further, chemometrics based quantitative evaluation of biosimilarity has been performed by combining the data obtained from analytical characterization platform. The analysis of the analytical, functional and chemometric results revealed significant levels of similarity, with biosimilar4 being the sole exception. Despite being within product specifications, Biosimilar4 displayed significant deviations with respect to critical quality attributes, including a lower proportion of monomer content, a larger percentage of basic charge variant species, and a lower proportion of aglycosylated glycoform.

Randomized Trial of Biosimilar XSB-001 versus Reference Ranibizumab in Patients with Neovascular Age-Related Macular Degeneration

OBJECTIVE

To evaluate the efficacy, safety, and immunogenicity of a ranibizumab biosimilar candidate (XSB-001) versus reference product (Lucentis) for neovascular age-related macular degeneration (nAMD).

DESIGN

Phase III, multicenter, randomized, double-masked, parallel-group study.

PARTICIPANTS

Patients with nAMD.

METHODS

Eligible patients were randomized (1:1) to receive intravitreal injections of XSB-001 or reference ranibizumab (0.5 mg [0.05 ml]) in the study eye once every 4 weeks for 52 weeks. Efficacy and safety assessments continued through 52 weeks of treatment.

MAIN OUTCOME MEASURES

Primary end point was change from baseline in best-corrected visual acuity (BCVA) by ETDRS letters at week 8. Biosimilarity was concluded if the 2-sided 90% confidence interval (CI) (United States) or 95% CI (rest of world) for the difference in least-squares (LS) mean change in BCVA at week 8 between treatment groups was within the predefined equivalence margin of ± 3.5 letters.

RESULTS

In total, 582 patients (n = 292 XSB-001, n = 290 reference ranibizumab) were randomized. Mean age was 74.1 years, most patients (85.2%) were White, and 55.8% were women. Mean BCVA score at baseline was 61.7 and 61.5 ETDRS letters in the XSB-001 and reference ranibizumab groups, respectively. At week 8, the LS mean (standard error [SE]) change in BCVA from baseline was 4.6 (0.5) ETDRS letters in the XSB-001 group and 6.4 (0.5) letters in the reference ranibizumab group (LS mean [SE] treatment difference: -1.8 [0.7] ETDRS letters; 90% CI, -2.9 to -0.7; 95% CI, -3.1 to -0.5). The 90% CI and 95% CI for LS mean difference in change from baseline were within the predefined equivalence margin. At week 52, LS mean (SE) change in BCVA was 6.4 (0.8) and 7.8 (0.8) letters, respectively (LS mean [SE] treatment difference, -1.5 [1.1] ETDRS letters; 90% CI, -3.3 to 0.4; 95% CI, -3.6 to 0.7). There were no clinically meaningful differences between treatments in anatomical, safety, or immunogenicity end points through week 52.

CONCLUSIONS

XSB-001 demonstrated biosimilarity to reference ranibizumab in patients with nAMD. Treatment with XSB-001 for 52 weeks was generally safe and well tolerated, with a safety profile similar to the reference product.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Twenty Years of Anti-Vascular Endothelial Growth Factor Therapeutics in Neovascular Age-Related Macular Degeneration Treatment

Neovascular age-related macular degeneration (nAMD) is the primary disastrous retinal disease that leads to blindness in the elderly population. In the early 2000s, nAMD resulted in irreversible vision loss and blindness with no available treatment options. However, there have been breakthrough advances in the drug development of anti-angiogenic biological agents over the last two decades. The primary target molecule for treating nAMD is the vascular endothelial growth factor (VEGF), and there are currently several anti-VEGF drugs such as bevacizumab, ranibizumab, and aflibercept, which have made nAMD more manageable than before, thus preventing vision loss. Nevertheless, it should be noted that these anti-VEGF drugs for nAMD treatment are not effective in more than half of the patients, and even those who initially gain visual improvements lose their vision over time, along with potential deterioration in the geography of atrophy. As a result, there have been continuous endeavors to improve anti-VEGF agents through better efficacy, fewer doses, expanded intervals, and additional targets. This review describes past and current anti-VEGF therapeutics used to treat nAMD and outlines future directions to improve the effectiveness and safety of anti-VEGF agents.

Intravitreal Anti-Vascular Endothelial Growth Factor Therapies for Retinal Disorders

Vascular endothelial growth factors (VEGFs) are key mediator of retinal and choroidal neovascularization as well as retinal vascular leakage leading to macular edema. As such, VEGF plays an important role in mediating visually significant complications associated with common retinal disorders such as diabetic retinopathy, retinal vein occlusion, and age-related macular degeneration. Various drugs that inhibit vascular endothelial growth factors (anti-VEGF therapies) have been developed to minimize vision loss associated with these disorders. These drugs are injected into the vitreous cavity in a clinic setting at regular intervals. This article provides an overview of the various anti-VEGF drugs used in ophthalmology and the common retinal conditions that benefit from this therapy.

Systematic review of efficacy and meta-analysis of safety of ranibizumab biosimilars relative to reference ranibizumab anti-VEGF therapy for nAMD treatment

TOPIC

This systematic review and meta-analysis provides a summary of the efficacy and safety of ranibizumab biosimilars relative to reference ranibizumab anti-vascular endothelial growth factor (VEGF) therapy for the treatment of neovascular age-related macular degeneration (nAMD).

METHODS

We conducted systematic searches from January 2003 to August 2022 on Ovid MEDLINE, EMBASE and the Cochrane Controlled Register of Trials. We included studies reporting changes in early treatment diabetic retinopathy study-measured best-corrected visual acuity (BCVA), number of patients who lost or gained more than 15 letters in BCVA from baseline, changes in retinal thickness and adverse events between treatment arms. The following studies were excluded: studies that did not report visual outcomes following biosimilar and reference ranibizumab intravitreal injections, study arms combining anti-VEGF agents with laser or steroid injections, sham injections as a control comparator, studies without English full texts and non-comparative, observational study design.

RESULTS

Five studies reported on four randomised controlled trials (RCTs) and 1544 eyes at baseline were included in this systematic review and meta-analysis. The studies in our systematic review found no significant differences between reference ranibizumab and ranibizumab biosimilar medications (FYB201, SB11, RanizuRel and Lupin's ranibizumab) for visual and anatomical outcomes. No significant differences were detected between biosimilar and reference ranibizumab for treatment emergent adverse events (risk ratio, RR 1.06, 95% CI (0.91 to 1.23), p=0.45, I²=52%) or IOP-related adverse events with significant heterogeneity (RR 2.59, 95% CI (0.11 to 62.25), p=0.56, I²=76%).

CONCLUSION

This systematic review of four RCTs demonstrated no significant difference in visual outcomes, retinal thickness outcomes, as well as meta-analysis of adverse events between biosimilar and reference ranibizumab therapies for nAMD treatment.

Ocular Delivery of Therapeutic Agents by Cell-Penetrating Peptides

Cell-penetrating peptides (CPPs) are short peptides with the ability to translocate through the cell membrane to facilitate their cellular uptake. CPPs can be used as drug-delivery systems for molecules that are difficult to uptake. Ocular drug delivery is challenging due to the structural and physiological complexity of the eye. CPPs may be tailored to overcome this challenge, facilitating cellular uptake and delivery to the targeted area. Retinal diseases occur at the posterior pole of the eye; thus, intravitreal injections are needed to deliver drugs at an effective concentration in situ. However, frequent injections have risks of causing vision-threatening complications. Recent investigations have focused on developing long-acting drugs and drug delivery systems to reduce the frequency of injections. In fact, conjugation with CPP could deliver FDA-approved drugs to the back of the eye, as seen by topical application in animal models. This review summarizes recent advances in CPPs, protein/peptide-based drugs for eye diseases, and the use of CPPs for drug delivery based on systematic searches in PubMed and clinical trials. We highlight targeted therapies and explore the potential of CPPs and peptide-based drugs for eye diseases.

Age-related macular degeneration

Age-related macular degeneration is an increasingly important public health issue due to ageing populations and increased longevity. Age-related macular degeneration affects individuals older than 55 years and threatens high-acuity central vision required for important tasks such as reading, driving, and recognising faces. Advances in retinal imaging have identified biomarkers of progression to late age-related macular degeneration. New treatments for neovascular age-related macular degeneration offer potentially longer-lasting effects, and progress is being made towards a treatment for atrophic late age-related macular degeneration. An effective intervention to slow progression in the earlier stages of disease, or to prevent late age-related macular degeneration development remains elusive, and our understanding of underlying mechanistic pathways continues to evolve.

An Institutional Guide for Formulary Decisions of Biosimilars

Biologics have changed the landscape for the management of many debilitating chronic diseases but account for a significant expenditure of medications globally. Fortunately, advances in technology paved the way for the introduction of biosimilars, which are highly similar to the originator biologics. In the quest to reduce the budget impact of biologics, organizations have begun to adopt biosimilars. Institutions evaluating biosimilars for inclusion in the hospital formulary must make informed formulary decisions by conducting a thorough review of key elements for evaluation of biosimilars and address the multidimensional aspects during the selection process of different biosimilar products. Therefore, we aim to present an institutional guide of these elements to inform formulary decisions. These key elements include biosimilar evaluation for formulary addition; regulatory approval; substitution, interchangeability, and switching; extrapolation; product characteristics, manufacturing, and supply chain issues; pharmacoeconomic evaluations; traceability, nomenclature, and coding; education; and pharmacovigilance.

Diabetic Macular Edema: Current Understanding, Molecular Mechanisms and Therapeutic Implications

Diabetic retinopathy (DR), with increasing incidence, is the major cause of vision loss and blindness worldwide in working-age adults. Diabetic macular edema (DME) remains the main cause of vision impairment in diabetic patients, with its pathogenesis still not completely elucidated. Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of DR and DME. Currently, intravitreal injection of anti-VEGF agents remains as the first-line therapy in DME treatment due to the superior anatomic and functional outcomes. However, some patients do not respond satisfactorily to anti-VEGF injections. More than 30% patients still exist with persistent DME even after regular intravitreal injection for at least 4 injections within 24 weeks, suggesting other pathogenic factors, beyond VEGF, might contribute to the pathogenesis of DME. Recent advances showed nearly all the retinal cells are involved in DR and DME, including breakdown of blood-retinal barrier (BRB), drainage dysfunction of Müller glia and retinal pigment epithelium (RPE), involvement of inflammation, oxidative stress, and neurodegeneration, all complicating the pathogenesis of DME. The profound understanding of the changes in proteomics and metabolomics helps improve the elucidation of the pathogenesis of DR and DME and leads to the identification of novel targets, biomarkers and potential therapeutic strategies for DME treatment. The present review aimed to summarize the current understanding of DME, the involved molecular mechanisms, and the changes in proteomics and metabolomics, thus to propose the potential therapeutic recommendations for personalized treatment of DME.

Current and Novel Therapeutic Approaches for Treatment of Diabetic Macular Edema

Diabetic macular edema (DME) is a major ocular complication of diabetes mellitus (DM), leading to significant visual impairment. DME's pathogenesis is multifactorial. Focal edema tends to occur when primary metabolic abnormalities lead to a persistent hyperglycemic state, causing the development of microaneurysms, often with extravascular lipoprotein in a circinate pattern around the focal leakage. On the other hand, diffusion edema is due to a generalized breakdown of the inner blood-retinal barrier, leading to profuse early leakage from the entire capillary bed of the posterior pole with the subsequent extravasation of fluid into the extracellular space. The pathogenesis of DME occurs through the interaction of multiple molecular mediators, including the overexpression of several growth factors, including vascular endothelial growth factor (VEGF), insulin-like growth factor-1, angiopoietin-1, and -2, stromal-derived factor-1, fibroblast growth factor-2, and tumor necrosis factor. Synergistically, these growth factors mediate angiogenesis, protease production, endothelial cell proliferation, and migration. Treatment for DME generally involves primary management of DM, laser photocoagulation, and pharmacotherapeutics targeting mediators, namely, the anti-VEGF pathway. The emergence of anti-VEGF therapies has resulted in significant clinical improvements compared to laser therapy alone. However, multiple factors influencing the visual outcome after anti-VEGF treatment and the presence of anti-VEGF non-responders have necessitated the development of new pharmacotherapies. In this review, we explore the pathophysiology of DME and current management strategies. In addition, we provide a comprehensive analysis of emerging therapeutic approaches to the treatment of DME.