Brolucizumab for the Treatment of Degenerative Macular Conditions: A Review of Clinical Studies

The Safety of Recently Approved Therapeutics in Age-Related Macular Degeneration

Recent developments in treatments for both forms of advanced age-related macular degeneration (AMD) have led to the approval of multiple agents and modalities within the last few years. Five new medications for both neovascular AMD (nAMD) and geographic atrophy (GA) secondary to nonexudative AMD (neAMD) have been FDA-approved within the last 5 years, along with a new device designed for sustained drug delivery for nAMD. In nAMD, the newest agents approved by the FDA are brolucizumab (Novartis Pharmaceuticals, Basel, Switzerland), faricimab (F. Hoffman-La Roche, Basel, Switzerland), aflibercept 8 mg (Regeneron Pharmaceuticals, Tarrytown, NY, USA), and a new device in the port delivery system with ranibizumab (Genentech, San Francisco, CA, USA). The first agents FDA-approved for GA secondary to neAMD are pegcetacoplan (Apellis Pharmaceuticals, Waltham, MA, USA) and avacincaptad pegol (Iveric Bio, Parsippany, NJ, USA). Evaluation of safety in both clinical trials and the real-world has been of paramount importance after the approval of these newest agents to understand their effects in real patients. Real-world data, as demonstrated in both registrational studies along with retrospective chart review studies, has shown to be an important factor in the implementation of newer drugs, along with the treatment decisions that physicians choose to make regarding their dosing and follow-up. This review article discusses the safety of the most recently approved FDA as seen in both clinical trials and real-world studies.

Adverse events associated with brolucizumab: a disproportionality analysis of the FDA adverse event reporting system (FAERS)

BACKGROUND

The safety information of brolucizumab primarily comes from clinical trials experience. This study aimed to explore the ocular and systemic adverse events (AEs) associated with brolucizumab among real-world patients through data mining the FDA Adverse Event Reporting System (FAERS) database.

METHODS

AE reports submitted to the FAERS database between October 2019 and March 2023 were extracted. The reporting odds ratio was used to evaluate AE signals associated with brolucizumab.

RESULTS

There were 4,380,839 AE reports extracted from the FAERS database, and 3,313 of which were with brolucizumab as primary suspected. A total of 150 ocular AE signals were identified. Ninety-nine were known ocular AEs listed in brolucizumab' label, primarily including vision-related AEs, intraocular infections, and retinal disorders. Fifty-one were unexpected ocular AE signals, including keratic precipitates, retinal perivascular sheathing, dry eye, glaucoma, etc. Meanwhile, several serious systemic AE signals, including arterial thromboembolic events and rhinorrhea, were also identified.

CONCLUSIONS

Several unexpected ocular and systemic AE signals associated with brolucizumab were identified through data mining of the FAERS database.

Generation of rabbit single-chain variable fragments with different physicochemical and biological properties by complementary determining region-grafting technology

In this study, we have demonstrated a complementary-determining region (CDR) grafting technology for the generation of rabbit scFvs with different antigen recognition and physicochemical properties. The antigen-binding affinity of the CDR-grafted anti-CRP scFv, C1R/B1R (V1), which was generated by the CDR/framework region (CDR/FR) definition based on the traditional numbering rule, was insufficient when compared to that of the original clone, C1R, suggesting that the amino acid residues outside the original CDRs might significantly contribute to antigen recognition in rabbit scFvs. We redefined new CDRs and FRs to maintain antigen-binding affinities through the extension of multiple amino acid residues for CDRH1 and CDRH2, based on the amino acid sequence alignments of rabbit scFvs isolated from phage libraries. The new version successfully maintained the antigen binding affinity. CDR-grafted scFvs possessing a common CDR sequence and different FR sequences were successfully generated based on this new CDR/FR definition, and their physicochemical properties were further investigated. The antigen-binding activities of rabbit scFvs on Maxisorp varied between the tested clones in sandwich ELISA, supporting the idea that the combination of CDR with different FRs might change the physicochemical properties of scFvs on a solid material. The CDR-grafted scFvs possessing a frame sequence of anti-CRP scFv C2R maintained the ability to bind to protein L and were successfully purified. Expression titers showed improved solubility by diminishing the amount of insoluble scFvs. Thus, the method developed in this study is promising for generating alternatives with strict antigen binding recognition and different physicochemical properties.

Anti-angiogenic biomolecules in neovascular age-related macular degeneration; therapeutics and drug delivery systems

Blindness in the elderly is often caused by age-related macular degeneration (AMD). The advanced type of AMD known as neovascular AMD (nAMD) has been linked to being the predominant cause of visual impairment in these people. Multiple neovascular structures including choroidal neovascular (CNV) membranes, fluid exudation, hemorrhages, and subretinal fibrosis, are diagnostic of nAMD. These pathological alterations ultimately lead to anatomical and visual loss. It is known that vascular endothelial growth factor (VEGF), a type of proangiogenic factor, mediates the pathological process underlying nAMD. Therefore, various therapies have evolved to directly target the disease. In this review article, an attempt has been made to discuss general explanations about this disease, all common treatment methods based on anti-VEGF drugs, and the use of drug delivery systems in the treatment of AMD. Initially, the pathophysiology, angiogenesis, and different types of AMD were described. Then we described current treatments and future treatment prospects for AMD and outlined the advantages and disadvantages of each. In this context, we first examined the types of therapeutic biomolecules and anti-VEGF drugs that are used in the treatment of AMD. These biomolecules include aptamers, monoclonal antibodies, small interfering RNAs, microRNAs, peptides, fusion proteins, nanobodies, and other therapeutic biomolecules. Finally, we described drug delivery systems based on liposomes, nanomicelles, nanoemulsions, nanoparticles, cyclodextrin, dendrimers, and composite vehicles that are used in AMD therapy.

Comparison between intravitreal brolucizumab and aflibercept in the treatment-naive central involved diabetic macular edema: One-year real-life case series

PURPOSE

To evaluate the effectiveness and safety of intravitreal brolucizumab (IVB) and intravitreal aflibercept (IVA) injections in the management of naive central involved diabetic macular edema (CIDME).

METHODS

This study included 45 treatment-naive eyes with CIDME. A complete ophthalmic examination, including BCVA and SD-OCT was performed. Patients were randomized to (IVB) or (IVA) groups. All participants received a loading phase of three consecutive intravitreal injections, then followed by a personalized treat and extend (T&E) regimen.

RESULTS

At 12-month follow-up, the mean numbers of injections in IVA and IVB groups were 7.25  ±  0.53 and 6.3  ±  0.45, respectively (P < 0.0001). The IVA group showed a significant increase of the mean BCVA from 0.66  ±  0.15 logMAR (50.9  ±  7.7 letters) to 0.41  ±  0.19 logMAR (63.7  ±  10.8 letters). Mean CFT decreased significantly from 441.2  ±  35.7 μm to 281.3  ±  18.4 μm. The IVB group showed a significant increase of mean BCVA from 0.65  ±  0.16 logMAR (52.1  ±  7.9 letters) to 0.39  ±  0.17 logMAR (65.3  ±  8.7 letters). Mean CFT decreased significantly from 437.2  ±  41.9 μm to 275.5  ±  21.7 μm.No significant difference between both groups in terms of the vision improvement and the reduction of CFT was reported, whereas a statistical difference was observed in terms of intravitreal injections (IVI) numbers. No ocular complications were reported.

CONCLUSIONS

This case series highlights the effectiveness of both brolucizumab and aflibercept in the treatment of CIDME with a lower frequency of injection in brolucizumab group lowering the burden of IVI in this cohort.

Functional and anatomical outcomes of brolucizumab for nAMD in a real-life setting

To report long-term outcomes of brolucizumab in neovascular age-related macular degeneration (nAMD) treatment. Records from 74 patients were retrospectively reviewed. Both naïve eyes and those previously treated with other antiVEGF agents were included. Primary outcomes included variation in best corrected visual acuity (BCVA), central subfield thickness (CST), intraretinal fluid (IRF), subretinal fluid (SRF), and pigment epithelial detachment (PED) dimensions. Outcomes were reviewed after the loading phase, at week 24, and at last follow-up. IOI occurrence represented the secondary outcome. BCVA improved significantly in both groups. In switched eyes, IRF and SRF were significantly reduced at every timepoint, with CST reduction from week 24 (p = 0.005). In naïve group, CST decreased from the loading phase (p = 0.006) and all patients showed dry macula from week 24. A significant reduction in PED maximum high was demonstrated in both groups. In seven naïve eyes, PED completely reabsorbed; a slight increase in PED horizontal maximal diameter was also observed from week 24. IOI occurred in 5.4% of cases. In conclusion, brolucizumab showed a strong drying effect, permitting functional improvement together with fluid reabsorption and an encouraging modification of PED dimension, especially on naïve patients. These results together with the extension of treatment intervals make brolucizumab an efficient therapeutic strategy for nAMD.

Brolucizumab in age-related macular neovascularization (BRAIN study): Efficacy, optical coherence tomography biomarkers, and safety profile

BACKGROUND

Brolucizumab is a new anti-vascular endothelial growth factor (anti-VEGF) in the treatment of neovascular age-related macular degeneration (nAMD) and idiopathic polypoidal choroidal vasculopathy (IPCV).

MATERIALS AND METHODS

A retrospective, consecutive, interventional study was conducted from a tertiary eye hospital, in which treatment-naïve and treatment-switch patients were included. They underwent an intravitreal injection of brolucizumab. The decision to reinject was made based on the presence of fluid on spectral domain optical coherence tomography (SD-OCT) or worsening of vision at follow-up. Outcome measures were changes in best-corrected visual acuity (BCVA), central subfield thickness (CST), fluid (subretinal/intraretinal/sub-retinal pigment epithelium fluid) levels, and OCT biomarkers and safety analysis.

RESULTS

A total of 59 eyes of 50 patients with a total of 132 intravitreal injections were included. There was a statistically significant improvement (P < 0.05) in BCVA from baseline in logMAR treatment-naïve patients (mean BCVA at baseline 0.6 ± 0.41 and 0.37 ± 0.56). The mean baseline CST of all patients significantly reduced from 582.92 ± 233.11 µm at baseline to 474.06 ± 252.89 µm at the final treatment visit. Thirty-eight percent of patients showed complete resolution of SHRM after a single injection. The interval between each subsequent injection increased from a mean of 67 to 96 days in treatment-switch patients and from 47 to 151 days in treatment-naïve patients.

CONCLUSION

Brolucizumab promises reduced number of injections with longer treatment intervals.

PolySialic acid-nanoparticles inhibit macrophage mediated inflammation through Siglec agonism: a potential treatment for age related macular degeneration

Age-related macular degeneration (AMD) is a chronic, progressive retinal disease characterized by an inflammatory response mediated by activated macrophages and microglia infiltrating the inner layer of the retina. In this study, we demonstrate that inhibition of macrophages through Siglec binding in the AMD eye can generate therapeutically useful effects. We show that Siglecs-7, -9 and -11 are upregulated in AMD associated M0 and M1 macrophages, and that these can be selectively targeted using polysialic acid (PolySia)-nanoparticles (NPs) to control dampen AMD-associated inflammation. In vitro studies showed that PolySia-NPs bind to macrophages through human Siglecs-7, -9, -11 as well as murine ortholog Siglec-E. Following treatment with PolySia-NPs, we observed that the PolySia-NPs bound and agonized the macrophage Siglecs resulting in a significant decrease in the secretion of IL-6, IL-1β, TNF-α and VEGF, and an increased secretion of IL-10. In vivo intravitreal (IVT) injection of PolySia-NPs was found to be well-tolerated and safe making it effective in preventing thinning of the retinal outer nuclear layer (ONL), inhibiting macrophage infiltration, and restoring electrophysiological retinal function in a model of bright light-induced retinal degeneration. In a clinically validated, laser-induced choroidal neovascularization (CNV) model of exudative AMD, PolySia-NPs reduced the size of neovascular lesions with associated reduction in macrophages. The PolySia-NPs described herein are therefore a promising therapeutic strategy for repolarizing pro-inflammatory macrophages to a more anti-inflammatory, non-angiogenic phenotype, which play a key role in the pathophysiology of non-exudative AMD.

Faricimab: Transforming the Future of Macular Diseases Treatment - A Comprehensive Review of Clinical Studies

Degenerative eye conditions such as age-related macular degeneration (AMD), diabetic retinopathy, and retinal vein occlusion are major contributors to significant vision loss in developed nations. The primary therapeutic approach for managing complications linked to these diseases involves the intravitreal delivery of anti-vascular endothelial growth factor (VEGF) treatments. Faricimab is a novel, humanised, bispecific antibody that simultaneously binds all VEGF-A isoforms and Angiopoietin-2, which has been approved by regulatory agencies, such as the US Food and Drug Administration (FDA), the UK Medicines and Healthcare products Regulatory Agency (MHRA) and the European Medicines Agency (EMA), for the treatment of neovascular AMD and diabetic macular oedema (DMO). Intravitreal faricimab holds the promise of reducing the treatment burden for patients with these conditions by achieving comparable or superior therapeutic outcomes with fewer clinic visits. The scope of faricimab's application includes addressing complex macular conditions such as DMO. This review intends to elucidate the distinctive pharmacological characteristics of faricimab and provide an overview of the key clinical trials and real-world studies that assess its effectiveness and safety in treating degenerative macular diseases.

Preclinical modeling of intravitreal suspensions

There are a number of obstacles that complicate the development of intravitreal delivered small molecules therapies. One serious complication is the potential need for complex polymer depot formulations early in the drug discovery process. The development of such formulations often requires substantial investment of time and material which may not be readily available in preclinical development. Herein I present a diffusion limited pseudo-steady state model to provide prediction of drug release from an intravitreally administered suspension formulation. By using such a model, a preclinical formulator may be able to more confidently determine if development of a complex formulation is required or if a simple suspension may work to support a study design. In this report, the model is used to predict the intravitreal preformance of two different molecules (triamcinolone acetonide and GNE-947) at multiple dose levels in rabbit eyes as well as provide a prediction for the performance of a marketed formulation of Trimacinolone Acetonide in humans.

Ocular Delivery of Therapeutic Proteins: A Review

Therapeutic proteins, including monoclonal antibodies, single chain variable fragment (ScFv), crystallizable fragment (Fc), and fragment antigen binding (Fab), have accounted for one-third of all drugs on the world market. In particular, these medicines have been widely used in ocular therapies in the treatment of various diseases, such as age-related macular degeneration, corneal neovascularization, diabetic retinopathy, and retinal vein occlusion. However, the formulation of these biomacromolecules is challenging due to their high molecular weight, complex structure, instability, short half-life, enzymatic degradation, and immunogenicity, which leads to the failure of therapies. Various efforts have been made to overcome the ocular barriers, providing effective delivery of therapeutic proteins, such as altering the protein structure or including it in new delivery systems. These strategies are not only cost-effective and beneficial to patients but have also been shown to allow for fewer drug side effects. In this review, we discuss several factors that affect the design of formulations and the delivery of therapeutic proteins to ocular tissues, such as the use of injectable micro/nanocarriers, hydrogels, implants, iontophoresis, cell-based therapy, and combination techniques. In addition, other approaches are briefly discussed, related to the structural modification of these proteins, improving their bioavailability in the posterior segments of the eye without affecting their stability. Future research should be conducted toward the development of more effective, stable, noninvasive, and cost-effective formulations for the ocular delivery of therapeutic proteins. In addition, more insights into preclinical to clinical translation are needed.

Monoclonal Antibodies: A Therapeutic Option for the Treatment of Ophthalmic Diseases of the Eye Posterior Segment

The eye is an organ that allows us to observe the outside world. Pathologies of the eye's posterior segment, such as glaucoma, macular degeneration, diabetic retinopathy, uveitis, and retinoblastoma, cause vision loss. Traditional treatments consist of applying topical medications that do not penetrate properly or using high doses that generate adverse effects. Different laser surgeries stop the pathology's progression but do not allow visual improvement. So, an alternative is to use monoclonal antibodies, proteins produced by different processes that selectively bind to metabolites associated with diseases, reducing the adverse effects of traditional treatments and improving the application of the drug in the area. The two main molecular targets are TNF (adalimumab, infliximab, and certolizumab pegol) and VEGF (bevacizumab and ranibizumab); other possibilities are under investigation.