Ziv-aflibercept: A cost-effective, off-label, highly potent antagonist of vascular endothelial growth factor

Diabetic Macular Edema Management: A Review of Anti-Vascular Endothelial Growth Factor (VEGF) Therapies

Diabetic macular edema (DME) is a major cause of vision impairment in diabetic individuals, characterized by fluid accumulation in the macula due to a breakdown of the blood-retinal barrier (BRB). This review article explores the role of anti-vascular endothelial growth factor (anti-VEGF) therapies in the management of DME. Anti-VEGF treatments, including ranibizumab, bevacizumab, and aflibercept, have revolutionized DME management by targeting VEGF, a key mediator in DME pathogenesis. We critically examined the efficacy of these therapies in reducing macular edema and improving visual acuity, assessed their safety and tolerability, and explored the variability in treatment response. The review highlights the latest advancements and future directions in anti-VEGF therapy, including novel drug delivery systems and emerging treatment paradigms. By providing a comprehensive overview of current anti-VEGF therapies, this review seeks to inform clinical practice, guide future research, and contribute to improved patient outcomes in DME management.

Therapeutic Fusion Proteins

Therapeutic fusion proteins are a class of hybrid constructs that combine distinct biomolecules into a single platform with the additive effects of the components. The ability to fuse two unrelated proteins provides a means to localize mechanisms to better treat a range of diseases. Fusion proteins can be designed to impart diverse functions, including increasing half-life, providing targeting, and enabling sustained signaling. Of these, half-life extenders, which are fused to a therapeutic protein to increase exposure, are the most established group of fusion proteins, with many clinical successes. Rapid advances in antibody and antibody-derivative technology have enabled the fusion of targeting domains with therapeutic proteins. An emerging group of therapeutic fusion proteins has two separate active functions. Although most research for therapeutic fusion proteins focuses on cancer, prior successes provide a foundation for studies into other diseases as well. The exponential emergence of biopharmaceuticals gives precedence for increased research into therapeutic fusion proteins for a multitude of diseases.

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.

Effectiveness of the Use of Three-Dose Intravitreal Ziv-Aflibercept in the Management of Diabetic Macular Edema in a Real-Life Setting

Purpose

It has been reported that intravitreal Ziv-aflibercept is a safe and effective drug for the treatment of diabetes macular edema (DME). The objective of this study was to evaluate in a real-life setting, the efficacy of intravitreal Ziv-aflibercept in the treatment of DME after the administration of three consecutive monthly doses.

Methods

A single arm, prospective cohort study. We included patients with DME who received three doses of intravitreal Ziv-aflibercept. Data such as best corrected visual acuity (BCVA) and tomographic biomarkers before treatment and a month after the third dose were collected. DME was staged using the Panozzo classification.

Results

Thirty-eight patients participated for a total of 53 eyes. The mean age was 59 ± 8.1 years. We observed significant changes after the third dose in the parameters studied (BCVA in LogMAR pre-treatment (0.6 ± 0.33) and post-treatment (0.4 ± 0.29) [p<0.001], macular thickness pre-treatment (501 ± 167 µm) and post-treatment (324 ± 114 µm) [p<0.001], macular volume pre-treatment 10.8 (7.5-17.8) mm³ and post-treatment 9.3 (0-13.6) mm³ [p<0.005]). And 73.6% of the patients presented an advanced severe stage during their pre-treatment evaluation and after post-treatment, 64.2% of the patients no longer presented edema. No systemic or ocular adverse events occurred.

Conclusion

The use of three consecutive monthly doses of intravitreal Ziv-aflibercept in a real-life setting is effective and safe in the management of diabetic macular edema.

An Introduction to Biosimilars for the Treatment of Retinal Diseases: A Narrative Review

Biological therapies have revolutionized the treatment of disease across a number of therapeutic areas including retinal diseases. However, on occasion, such treatments may be relatively more expensive compared to small molecule therapies. This can restrict patient access and treatment length leading to suboptimal clinical outcomes. Several biosimilar candidates of ranibizumab and aflibercept are currently in development and the first biosimilar of ranibizumab received EMA approval in August and FDA approval in September 2021. Biosimilars are biological medicines that are highly similar to an already-approved biological medicine (reference product). The physicochemical and clinical similarity of a biosimilar is determined by a rigorous analytical and clinical program, including extensive pharmacokinetic and pharmacodynamic analysis with phase III equivalence studies where appropriate. These phase III studies are carried out in a patient population that is representative of all of the potential approved therapeutic indications of the originator product and the most sensitive for detecting potential differences between the biosimilar and the reference product. Biosimilars have been used successfully across a wide range of therapeutic areas for the past 15 years where they have achieved substantial cost savings that can be reinvested into healthcare systems without affecting the quality of patient care. The current review provides an introduction to biosimilars with the aim of preparing retinal specialists for discussing these products with their patients.

The sterility, stability and efficacy of repackaged ziv-aflibercept for intravitreal administration

To evaluate the sterility, stability, and efficacy of repackaged ziv-aflibercept in 1-mL plastic tuberculin syringes for intravitreal injection after storage for up to 90 days at controlled (4 °C) and ambient (25.8 °C) temperature. A total of 168 tuberculin-type 1-mL syringes were prepared containing ziv-aflibercept (100 mg/4 mL). Samples were stored at 4 °C and 25.8 °C for 0, 3, 7, 14, 21, 28, 60, and 90 days. At each time point, four samples were evaluated for the stability and binding affinity of anti-VEGF to VEGF (efficacy) using enzyme-linked immunosorbent assays (ELISAs). All samples were analyzed for microbial growth. No microbial growth was obtained from any of the ziv-aflibercept samples during each time point, indicating that the repackaged ziv-aflibercept stored at 4 °C and 25.8 °C remained sterile. ELISA analysis revealed no significant decrease in concentration, and binding affinity was observed, indicating that the stability and efficacy were preserved. However, the concentration of ziv-aflibercept decreased less than the minimum expected concentration of 8 ng/mL after 60 days at 4 °C and after 30 days at 25.8 °C. The repackaged anti-VEGF drug ziv-aflibercept does not lose stability or efficacy and remains uncontaminated if prepared under sterile conditions and stored at 4 °C for up to 60 days or stored at 25.8 °C for up to 30 days.

Emerging Therapeutic Agents for Colorectal Cancer

There are promising new therapeutic agents for CRC patients, including novel small-molecule inhibitors and immune checkpoint blockers. We focused on emerging CRC’s therapeutic agents that have shown the potential for progress in clinical practice. This review provides an overview of tyrosine kinase inhibitors targeting VEGF and KIT, BRAF and MEK inhibitors, TLR9 agonist, STAT3 inhibitors, and immune checkpoint blockers (PD1/PDL-1 inhibitors), for which recent advances have been reported. These new agents have the potential to provide benefits to CRC patients with unmet medical needs.

Treatment of Macular Edema in Vascular Retinal Diseases: A 2021 Update

Macular edema (ME) is associated with various conditions; however, the main causes of ME are retinal vein occlusion (RVO) and diabetes. Laser photocoagulation, formerly the gold standard for the treatment of ME, has been replaced by anti-vascular endothelial growth factor (anti-VEGF) intravitreal injections. Despite its efficiency, this treatment requires frequent injections to preserve the outcomes of anti-VEGF therapy, and as many patients do not sufficiently respond to the treatment, ME is typically a chronic condition that can lead to permanent visual impairment. Generalized recommendations for the treatment of ME are lacking, which highlights the importance of reviewing treatment approaches, including recent anti-VEGFs, intravitreal steroid implants, and subthreshold micropulse lasers. We reviewed relevant studies, emphasizing the articles published between 2019 and 2021 and using the following keywords: macular edema, diabetic macular edema, retinal vein occlusion, laser photocoagulation, anti-VEGF, and intravitreal injections. Our results revealed that a combination of different treatment methods may be beneficial in resistant cases. Additionally, artificial intelligence (AI) is likely to help select the best treatment option for patients in the near future.

Intravitreal Therapy for Diabetic Macular Edema: An Update

Diabetic macular edema (DME) represents a prevalent and disabling eye condition. Despite that DME represents a sight-threatening condition, it is also among the most accessible to treatment. Many different treatment options including photocoagulation, intravitreal medical treatment (either vascular endothelial growth factor inhibitors or corticosteroids therapies), and surgical removal are currently available. Although laser has been considered as the gold standard for many years, over the past several years vascular endothelial growth factor inhibitors (anti-VEGFs) have become first-line therapy. However, many patients do not adequately respond to them. With the development of sustained-release corticosteroid devices, steroids have gained a presence in the management of the DME. We review and update the role of anti-VEGF and intravitreal sustained-release corticosteroid management of DME. According to the currently available scientific evidence, the choice of one anti-VEGF over another critically depends on the baseline best-corrected visual acuity (BCVA). While aflibercept may be the drug of choice in low baseline BCVA, the three anti-VEGFs (bevacizumab, ranibizumab, and aflibercept) provided similar functional outcomes when the baseline BCVA was higher. DEX implants are a valuable option for treating DME, although they are usually seen as a second choice, particularly in those eyes that have an insufficient response to anti-VEGF. The new evidence suggested that, in eyes that did not adequately respond to anti-VEGF, switching to a DEX implant at the time to 3 monthly anti-VEGF injections provided better functional outcomes.

Ziv-aflibercept for Better Regulating Neovascular Age-Related Macular Degeneration (ZEBRA): A Prospective, Randomized Trial

OBJECTIVE

The purpose of this study is to determine if ziv-aflibercept is a safe and effective maintenance drug for nAMD.

STUDY DESIGN AND METHODS

This is a randomized, prospective, single-blinded trial. Inclusion criteria were active nAMD, prior anti-VEGF treatment, and BCVA ≤20/200. The treatment group received ziv-aflibercept. The control group continued their existing anti-VEGF regimen. The main outcome measures were BCVA, CFT, and safety.

RESULTS

Mean baseline BCVA was 1.58 ± 0.44 logMAR and 1.71 ± 0.39 logMAR in the control (n = 27) and treatment (n = 29) groups, respectively. After 24 months, the mean change in BCVA was 0.11 in the control group (equivalent to a loss of 5 ETDRS letters) and 0.01 logMAR in the treatment group (p = .48). Baseline CFT was 257 ± 33 μm and 247 ± 30 μm in the control and treatment groups, respectively, and after 24 months mean change in CFT was 26 μm and -5 μm (p = .24). There were no ocular or systemic adverse events during the study.

CONCLUSION

Ziv-aflibercept is a safe and effective as a maintenance drug for patients with nAMD. It may represent a cost-effective alternative to aflibercept and second-line therapy for eye resistant bevacizumab or ranibizumab.

Gene Therapy Intervention in Neovascular Eye Disease: A Recent Update

Aberrant growth of blood vessels (neovascularization) is a key feature of severe eye diseases that can cause legal blindness, including neovascular age-related macular degeneration (nAMD) and diabetic retinopathy (DR). The development of anti-vascular endothelial growth factor (VEGF) agents has revolutionized the treatment of ocular neovascularization. Novel proangiogenic targets, such as angiopoietin and platelet-derived growth factor (PDGF), are under development for patients who respond poorly to anti-VEGF therapy and to reduce adverse effects from long-term VEGF inhibition. A rapidly advancing area is gene therapy, which may provide significant therapeutic benefits. Viral vector-mediated transgene delivery provides the potential for continuous production of antiangiogenic proteins, which would avoid the need for repeated anti-VEGF injections. Gene silencing with RNA interference to target ocular angiogenesis has been investigated in clinical trials. Proof-of-concept gene therapy studies using gene-editing tools such as CRISPR-Cas have already been shown to be effective in suppressing neovascularization in animal models, highlighting the therapeutic potential of the system for treatment of aberrant ocular angiogenesis. This review provides updates on the development of anti-VEGF agents and novel antiangiogenic targets. We also summarize current gene therapy strategies already in clinical trials and those with the latest approaches utilizing CRISPR-Cas gene editing against aberrant ocular neovascularization.

Safety of Intravitreal Injection of Biosimilar of Aflibercept in Rabbit Eyes

Purpose

To assess the safety of biosimilar intravitreal aflibercept (CinnaGen Co., Iran) compared to the reference product (Eylea®; Bayer Schweiz AG, Zurich, Switzerland) in rabbit eyes through functional and histologic studies.

Methods

Forty New Zealand albino rabbits were recruited to the study and were divided into four groups to be sacrificed at 48 hours, one, two, and four weeks after injections. In each group, five rabbits received 0.05 mL (2 mg) biosimilar aflibercept in the right eye and 0.05 mL saline in the left eye as the control, and in a similar manner, the remaining five rabbits received the reference drug in the right eye and saline in the left eye. All the rabbits underwent comprehensive ophthalmic examination and electroretinography (ERG) tests at baseline and also just before enucleation at the specific predefined time points. The enucleated eyes were prepared for retinal toxicity histological examination.

Results

No retinal toxicity was observed based on histologic and ERG findings in all groups. Choroidal congestion was revealed after 1 week in an eye that was injected with biosimilar aflibercept, although the similar finding was detected in the contralateral eye which received saline. Also, one subject which received the reference drug showed chronic vitritis and lymphoplasmocytic reaction of the optic disc at week 4. The remaining subjects showed no histologic changes.

Conclusion

The 2 mg intravitreal injection of biosimilar aflibercept (CinnaGen Co., Iran) was found to be nontoxic in rabbit eyes in the short-term period. Further studies are required to warrant the efficacy and safety profile of the drug in human subjects.