Delivery Of Monoclonal Antibodies Research Articles

Monoclonal Antibody Delivery Using 3D Printed Biobased Hollow μNe3dle Arrays for the Treatment of Osteoporosis.

Transdermal microneedles have demonstrated promising potential as an alternative to typical drug administration routes for the treatment of various diseases. As microneedles offer lower administration burden with enhanced patient adherence and reduced ecological footprint, there is a need for further exploitation of microneedle devices. One of the main objectives of this work was to initially develop an innovative biobased photocurable resin with high biobased carbon content comprising isobornyl acrylate (IBA) and pentaerythritol tetraacrylate blends (50:50 wt/wt). The optimization of the printing and curing process resulted in μNe3dle arrays with durable mechanical properties and piercing capacity. Another objective of the work was to employ the 3D printed hollow μNe3dles for the treatment of osteoporosis in vivo. The 3D printed μNe3dle arrays were used to administer denosumab (Dmab), a monoclonal antibody, to osteoporotic mice, and the serum concentrations of critical bone minerals were monitored for six months to assess recovery. It was found that the Dmab administered by the 3D printed μNe3dles showed fast in vitro rates and induced an enhanced therapeutic effect in restoring bone-related minerals compared to subcutaneous injections. The findings of this study introduce a novel green approach with a low ecological footprint for 3D printing of biobased μNe3dles, which can be tailored to improve clinical outcomes and patient compliance for chronic diseases.

Engineering hyaluronic acid-based nanoassemblies for monoclonal antibody delivery – design, characterization, and biological insights

AbstractThe current spotlight of cancer therapeutics is shifting towards personalized medicine with the widespread use of monoclonal antibodies (mAbs). Despite their increasing potential, mAbs have an intrinsic limitation related to their inability to cross cell membranes and reach intracellular targets. Nanotechnology offers promising solutions to overcome this limitation, however, formulation challenges remain. These challenges are the limited loading capacity (often insufficient to achieve clinical dosing), the complex formulation methods, and the insufficient characterization of mAb-loaded nanocarriers. Here, we present a new nanocarrier consisting of hyaluronic acid-based nanoassemblies (HANAs) specifically designed to entrap mAbs with a high efficiency and an outstanding loading capacity (50%, w/w). HANAs composed by an mAb, modified HA and phosphatidylcholine (PC) resulted in sizes of ~ 100 nm and neutral surface charge. Computational modeling identified the principal factors governing the high affinity of mAbs with the amphiphilic HA and PC. HANAs composition and structural configuration were analyzed using the orthogonal techniques cryogenic transmission electron microscopy (cryo-TEM), asymmetrical flow field-flow fractionation (AF4), and small-angle X-ray scattering (SAXS). These techniques provided evidence of the formation of core-shell nanostructures comprising an aqueous core surrounded by a bilayer consisting of phospholipids and amphiphilic HA. In vitro experiments in cancer cell lines and macrophages confirmed HANAs’ low toxicity and ability to transport mAbs to the intracellular space. The reproducibility of this assembling process at industrial-scale batch sizes and the long-term stability was assessed. In conclusion, these results underscore the suitability of HANAs technology to load and deliver biologicals, which holds promise for future clinical translation.

A phase 2, open-label, 2-cohort study to evaluate patient preference for nivolumab (NIVO) + relatlimab (RELA) fixed-dose combination (FDC) subcutaneous (SC) vs NIVO + RELA FDC intravenous (IV) and NIVO SC vs NIVO IV in participants with melanoma.

TPS9619 Background: The oncology burden on healthcare resources and patients increases as the number of individuals with cancer grows, necessitating treatment options offering improved convenience to patients. SC delivery of monoclonal antibodies in various cancer indications has previously been shown to be effective, well tolerated, and preferred by patients over IV infusion. In CheckMate 67T (NCT04810078), noninferiority of exposure (time-averaged serum concentration at Day 28 and trough serum concentration at steady state) and efficacy (objective response rate by BICR) were previously reported for NIVO SC 1200 mg + recombinant human hyaluronidase PH20 (rHuPH20) vs IV in patients with locally advanced/metastatic clear cell renal cell carcinoma. RELATIVITY-127 (NCT05625399) is ongoing to establish exposure noninferiority of NIVO + RELA + rHuPH20 FDC SC to IV in patients with previously untreated metastatic/unresectable melanoma. This phase 2, open-label study CA224-1044 (NCT06101134) assesses patient preference for NIVO SC or NIVO + RELA FDC SC vs IV formulations after transitioning from IV to SC in patients with melanoma and aims to further characterize the safety profile of immuno-oncology therapy during IV-to-SC switch. Methods: Cohort 1 includes adult patients with previously untreated stage III (unresectable) or stage IV (metastatic) melanoma who will receive NIVO + RELA FDC IV every 4 weeks (Q4W) for 2 cycles (28-day cycle) followed by NIVO + RELA + rHuPH20 FDC SC Q4W until disease progression, unacceptable toxicity, or a maximum total treatment duration of 2 years, whichever comes first. Cohort 2 includes adult patients with completely resected stage IIB/C, stage III or stage IV melanoma who will receive NIVO IV Q4W for 2 cycles (28-day cycle) followed by NIVO SC + rHuPH20 Q4W until disease recurrence, unacceptable toxicity, or a maximum total treatment duration of 1 year, whichever comes first. The primary endpoint is the proportion of participants preferring the SC route of administration based on question 7 of the Patient Experience and Preference Questionnaire after the Cycle 4 Day 1 dose. This question evaluates patient preference for IV or SC or no preference in treatment administration and was previously used in CheckMate 8KX. Secondary endpoints include safety outcomes such as adverse events (AEs), serious AEs, treatment-related AEs, AEs leading to discontinuation, immune-mediated AEs, other events of special interest, injection/infusion-related AEs, deaths, and laboratory abnormalities. Safety is assessed for IV period, SC period (8 weeks each) and overall study period. Exploratory endpoints include additional measures of patient experience and preference for IV vs SC. The study is recruiting to enroll 50 patients per cohort. Clinical trial information: NCT06101134 .

Developing a synergistic rate-retarding polymeric implant for controlling monoclonal antibody delivery in minimally invasive glaucoma surgery

Monoclonal antibodies (mAbs) have garnered substantial attention within the field of ophthalmology and can be used to suppress scar formation after minimally invasive glaucoma surgeries. Here, by controlling mAb passive diffusion, we developed a polymeric, rate-controlling membrane reservoir loaded with poly(lactic-co-glycolic acid) microspheres to deliver mAb for several weeks. Different parameters were tested to ensure that the microspheres achieved a good quality characteristic, and our results showed that 1 %W/V emulsifier with 5 %W/V NaCl achieved mAb-loaded microspheres with the highest stability, encapsulation efficiency and minimal burst release. Then, we fabricated and compared 10 types of microporous films based on polylactic acid (PLA), polycaprolactone (PCL), and polyethylene glycol (PEG). Our results revealed distinct pore characteristics and degradation patterns in different films due to varying polymer properties, and all the polymeric film formulations showed good biocompatibility in both human trabecular meshwork cells and human conjunctival fibroblasts. Finally, the optimized microspheres were loaded into the reservoir-type polymeric implant assembled by microporous membranes with different surface coating modifications. The implant formulation, which was fabricated by 60 PCL: 40 PEG (3 %W/V) polymer with 0.1 %W/V poly(lactic-co-glycolic acid) barrier, exerted the best drug release profile that can sustained release mAb (83.6 %) for 4 weeks.

Investigating the Impact of Drone Transport on the Stability of Monoclonal Antibodies for Inter-Hospital Transportation

In the field of healthcare logistics, the reliance on conventional transport methods such as cars for the delivery of monoclonal antibodies (mAbs) is susceptible to challenges posed by traffic and infrastructure, leading to increased and unpredictable transport times. Recognizing the potential role of drones in mitigating these challenges, we aimed to investigate the impact of medical drone transport on the stability of mAbs. Compromised stability could lead to aggregation and immunogenicity, thereby jeopardizing the efficacy and safety of mAbs. We studied the transportation of vials as well as ready-to-administer infusion bags with blinatumomab, tocilizumab, and daratumumab. The methodology involved the measurement of both temperature and mechanical shock during drone transport. Moreover, the analytical techniques High Performance Size-Exclusion Chromatography (HP-SEC), Dynamic Light Scattering (DLS), Light Obscuration (LO), Micro-Flow Imaging (MFI), and Nanoparticle Tracking Analysis (NTA) were employed to comprehensively assess the presence of aggregates and particle formation. The key findings revealed no significant differences between car and drone transport, indicating that the stability of mAbs in both vials and infusion bags was adequately maintained during drone transport. This suggests that medical drones are a viable and reliable means for the inter-hospital transport of mAbs, paving the way for more efficient and predictable logistics in healthcare delivery.

Preparation and characterization of enzyme-responsive zwitterionic nanoparticles for monoclonal antibody delivery

Preparation and characterization of enzyme-responsive zwitterionic nanoparticles for monoclonal antibody delivery

Controlled release of therapeutic antibody using hydrolytically degradable microgels.

Monoclonal antibodies have gained significant interest as potential therapeutics for treating various diseases. However, these therapies are not always effective due to poor treatment compliance associated with multiple administrations and drug resistance. Thus, there is a growing interest in developing advanced monoclonal antibody delivery systems that can customize pharmacokinetics to enhance therapeutic outcomes. This work aimed to engineer hydrolytic 4-arm PEG maleimide (PEG-4MAL) microgels for the controlled delivery of therapeutic antibodies, specifically anti-angiogenic bevacizumab, to overcome the limitations of current monoclonal antibody therapies. Through a PEGylation reaction with a thiol-terminated PEG linker, the antibody was covalently conjugated to the macromer backbone before microgel synthesis. The PEGylation reaction was simple, effective, and did not affect antibody bioactivity. Antibody release kinetics was tuned by changing the concentration of the hydrolytic linker (0-2 mM) and/or PEG-4MAL:protein molar ratio (1000:1, 2000:1, and 5000:1) in the macromer precursor solution during microgel fabrication. The bioactivity of the released antibody was assessed on human umbilical endothelial vascular cells (HUVEC), demonstrating that extracts from hydrolytic microgels reduced cell proliferation over time. Collectively, this study demonstrates the development of highly tunable delivery platform based on degradable PEG-4MAL microgels that can be adapted for therapeutic antibody-controlled release.

Expanding the Reach of Monoclonal Antibodies: A Review of Synthetic Nucleic Acid Delivery in Immunotherapy.

Harnessing the immune system to combat disease has revolutionized medical treatment. Monoclonal antibodies (mAbs), in particular, have emerged as important immunotherapeutic agents with clinical relevance in treating a wide range of diseases, including allergies, autoimmune diseases, neurodegenerative disorders, cancer, and infectious diseases. These mAbs are developed from naturally occurring antibodies and target specific epitopes of single molecules, minimizing off-target effects. Antibodies can also be designed to target particular pathogens or modulate immune function by activating or suppressing certain pathways. Despite their benefit for patients, the production and administration of monoclonal antibody therapeutics are laborious, costly, and time-consuming. Administration often requires inpatient stays and repeated dosing to maintain therapeutic levels, limiting their use in underserved populations and developing countries. Researchers are developing alternate methods to deliver monoclonal antibodies, including synthetic nucleic acid-based delivery, to overcome these limitations. These methods allow for in vivo production of monoclonal antibodies, which would significantly reduce costs and simplify administration logistics. This review explores new methods for monoclonal antibody delivery, including synthetic nucleic acids, and their potential to increase the accessibility and utility of life-saving treatments for several diseases.

Leading Edge: Intratumor Delivery of Monoclonal Antibodies for the Treatment of Solid Tumors.

Immunotherapies based on immune checkpoint blockade have shown remarkable clinical outcomes and durable responses in patients with many tumor types. Nevertheless, these therapies lack efficacy in most cancer patients, even causing severe adverse events in a small subset of patients, such as inflammatory disorders and hyper-progressive disease. To diminish the risk of developing serious toxicities, intratumor delivery of monoclonal antibodies could be a solution. Encouraging results have been shown in both preclinical and clinical studies. Thus, intratumor immunotherapy as a new strategy may retain efficacy while increasing safety. This approach is still an exploratory frontier in cancer research and opens up new possibilities for next-generation personalized medicine. Local intratumor delivery can be achieved through many means, but an attractive approach is the use of gene therapy vectors expressing mAbs inside the tumor mass. Here, we summarize basic, translational, and clinical results of intratumor mAb delivery, together with descriptions of non-viral and viral strategies for mAb delivery in preclinical and clinical development. Currently, this is an expanding research subject that will surely play a key role in the future of oncology.

Homogeneity of antibody-drug conjugates critically impacts the therapeutic efficacy in brain tumors.

SUMMARYGlioblastoma multiforme (GBM) is the most aggressive and fatal disease of all brain tumor types. Most therapies rarely provide clinically meaningful outcomes in the treatment of GBM. Although antibody-drug conjugates (ADCs) are promising anticancer drugs, no ADCs have been clinically successful for GBM, primarily because of poor blood-brain barrier (BBB) penetration. Here, we report that ADC homogeneity and payload loading rate are critical parameters contributing to this discrepancy. Although both homogeneous and heterogeneous conjugates exhibit comparable in vitro potency and pharmacokinetic profiles, the former shows enhanced payload delivery to brain tumors. Our homogeneous ADCs provide improved antitumor effects and survival benefits in orthotopic brain tumor models. We also demonstrate that overly drug-loaded species in heterogeneous conjugates are particularly poor at crossing the BBB, leading to deteriorated overall brain tumor targeting. Our findings indicate the importance of homogeneous conjugation with optimal payload loading in generating effective ADCs for intractable brain tumors.

Disparities in COVID-19 Monoclonal Antibody Delivery: a Retrospective Cohort Study.

BackgroundDisparities in access to anti-SARS-CoV-2 monoclonal antibodies have not been well characterized.ObjectiveWe sought to explore the impact of race/ethnicity as a social construct on monoclonal antibody delivery.Design/PatientsFollowing implementation of a centralized infusion program at a large academic healthcare system, we reviewed a random sample of high-risk ambulatory adult patients with COVID-19 referred for monoclonal antibody therapy.Main MeasuresWe examined the relationship between treatment delivery, race/ethnicity, and other demographics using descriptive statistics, binary logistic regression, and spatial analysis.Key ResultsThere was no significant difference in racial composition between patients who did (n = 25) and patients who did not (n = 378) decline treatment (p = 0.638). Of patients who did not decline treatment, 64.8% identified as White, 14.8% as Hispanic/Latinx, and 11.1% as Black. Only 44.6% of Hispanic/Latinx and 31.0% of Black patients received treatment compared to 64.1% of White patients (OR 0.45, 95% CI 0.25–0.81, p = 0.008, and OR 0.25, 95% CI 0.12–0.50, p < 0.001, respectively). In multivariable analysis including age, race, insurance status, non-English primary language, county Social Vulnerability Index, illness severity, and total number of comorbidities, associations between receiving treatment and Hispanic/Latinx or Black race were no longer statistically significant (AOR 1.32, 95% CI 0.69–2.53, p = 0.400, and AOR 1.34, 95% CI 0.64–2.80, p = 0.439, respectively). However, patients who were uninsured or whose primary language was not English were less likely to receive treatment (AOR 0.16, 95% CI 0.03–0.88, p = 0.035, and AOR 0.37, 95% CI 0.15–0.90, p = 0.028, respectively). Spatial analysis suggested decreased monoclonal antibody delivery to Cook County patients residing in socially vulnerable communities.ConclusionsHigh-risk ambulatory patients with COVID-19 who identified as Hispanic/Latinx or Black were less likely to receive monoclonal antibody therapy in univariate analysis, a finding not explained by patient refusal. Multivariable and spatial analyses suggested insurance status, language, and social vulnerability contributed to racial disparities.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07603-4.

"Smart" Delivery of Monoclonal Antibodies from a Magnetic Responsive Microgel Nanocomposite.

"Smart" drug-delivery systems have significant potential to increase therapeutic efficiency, avoid undesired immune responses, and minimize drug side effects. Herein, we report on an innovative strategy to control the drug release process using two magneto-activated materials operating in the system. One of them, a polyvinyl alcohol (PVA)-diboronate (DB)-interpenetrated (IPN) alginate (Alg) microgel nanocomposite (PVA-DB-IPN-Alg) loaded with magnetic nanoparticles (MNPs), is acting as a drug-delivery system. The drugs or model (bio)molecules are loaded in the PVA-DB-IPN-Alg and then released upon receiving a magnetic signal. Another component of the system is represented with the MNPs functionalized with the glucose oxidase (GOx) enzyme, GOx-MNPs. The immobilized GOx biocatalytically produces H2O2 in the presence of glucose and oxygen, while the PVA-DB-IPN-Alg is decomposed/dissolved by reacting with H2O2. In the absence of a magnet, the biocatalytically produced H2O2 was mostly decomposed by the catalase enzyme present in the solution, thus not reaching the alginate microgel. Upon aggregation of these two types of particles induced by a magnet, the GOx-MNPs produced H2O2in situ increasing locally its concentration, degrading the PVA-DB-IPN, thus opening pores in the alginate hydrogel resulting in a faster release of the entrapped payload. The release of the payload was confirmed in physiological complex environments, exemplified with human serum, demonstrating the stability and functionality of the materials in biological fluids. The release rate was strongly dependent on the concentration of catalase but not dependent on glucose concentration. The magneto-induced release process was confirmed for the small model protein payload, such as bovine serum albumin (BSA), as well as the trastuzumab monoclonal antibody (TmAb). For the latter, the release rate was up to 3.3 times higher in the presence of the magnet than in the absence of it in the human serum. We expect that the drug-delivery concept developed by these materials can find useful applications in the emerging field of "smart" materials in immunotherapy.

Non-dermal applications of microneedle drug delivery systems.

Microneedles (MNs) are micron-scaled needles measuring 100 to 1000μm that were initially explored for delivery of therapeutic agents across the skin. Considering the success in transcutaneous drug delivery, the application of microneedles has been extended to different tissues and organs. The review captures the application of microneedles to the oral mucosa, the eye, vagina, gastric mucosa, nail, scalp, and vascular tissues for delivery of vaccines, biologics, drugs, and diagnostic agents. The technology has created easy access to the poorly accessible segments of eye to facilitate delivery of monoclonal antibodies and therapeutic agents in management of neovascular disease. Microporation has been reported to drastically improve the drug delivery through the poorly permeable nail plate. Curved microneedles and spatially designed microneedle cuffs have been found to be capable of delivering stem cells and therapeutic macromolecules directly to the cardiac tissue and the vascular smooth muscle cells, respectively. Besides being minimally invasive and patient compliant, the technology has the potential to offer viable solutions to deliver drugs through impermeable barriers owing to the ability to penetrate several biological barriers. The technology has been successful to overcome the delivery hurdles and enable direct delivery of drug to the target sites, thus maximizing the efficacy thereby reducing the required dose. This review is an attempt to capture the non-dermatological applications of microneedles being explored and provides an insight on the future trends in the field of microneedle technology. Pictorial representation of different microneedle application.

Integrase-Defective Lentiviral Vectors for Delivery of Monoclonal Antibodies against Influenza.

Delivering rapid protection against infectious agents to non-immune populations is a formidable public health challenge. Although passive immunotherapy is a fast and effective method of protection, large-scale production and administration of monoclonal antibodies (mAbs) is expensive and unpractical. Viral vector-mediated delivery of mAbs offers an attractive alternative to their direct injection. Integrase-defective lentiviral vectors (IDLV) are advantageous for this purpose due to the absence of pre-existing anti-vector immunity and the safety features of non-integration and non-replication. We engineered IDLV to produce the humanized mAb VN04-2 (IDLV-VN04-2), which is broadly neutralizing against H5 influenza A virus (IAV), and tested the vectors’ ability to produce antibodies and protect from IAV in vivo. We found that IDLV-transduced cells produced functional VN04-2 mAbs in a time- and dose-dependent fashion. These mAbs specifically bind the hemagglutinin (HA), but not the nucleoprotein (NP) of IAV. VN04-2 mAbs were detected in the serum of mice at different times after intranasal (i.n.) or intramuscular (i.m.) administration of IDLV-VN04-2. Administration of IDLV-VN04-2 by the i.n. route provided rapid protection against lethal IAV challenge, although the protection did not persist at later time points. Our data suggest that administration of mAb-expressing IDLV may represent an effective strategy for rapid protection against infectious diseases.

Ex-vivo delivery of monoclonal antibody (Rituximab) to treat human donor lungs prior to transplantation.

BackgroundEx-vivo lung perfusion (EVLP) is an innovative platform for assessing donor lungs in the pre-transplant window. In this study, we demonstrate an extension of its utility by administering the anti-CD20 monoclonal antibody, Rituximab, during EVLP. We hypothesized that this would lead to targeted depletion of allograft B-cells which may provide significant clinical benefit, including the potential to reduce latent Epstein-Barr virus (EBV) and decrease the incidence of post-transplant lymphoproliferative malignancies.MethodsTwenty human donor lungs rejected for transplantation were placed on EVLP with (n = 10) or without (n = 10) 500 mg of Rituximab. Safety parameters such as lung physiology and inflammatory cytokines were evaluated. We measured the delivery efficacy through flow cytometry, immunohistochemistry and ELISA. An in-vitro culture assay, in the presence of complement, was further conducted to monitor whether B-cell depletion would occur in Rituximab-perfused samples.FindingsRituximab was successfully delivered to human lungs during EVLP as evidenced by flow cytometric binding assays where lung tissue and lymph node biopsies demonstrated occupied CD20 epitopes after perfusion with the antibody. Lymph nodes from Rituximab perfusions demonstrated a 10.9 fold-reduction in CD20+ staining compared to controls (p = 0.0003). In lung tissue, Rituximab resulted in an 8.75 fold-reduction in CD20+ staining relative to controls (p = 0.0002). This decrease in CD20+ binding illustrates the successful delivery and occupation of epitopes after perfusion with the Rituximab. No apparent safety concerns were seen as exhibited by markers associated with acute cell injury (e.g., proinflammatory cytokines), cell death (e.g., TUNEL staining), or pulmonary physiology. In a post-perfusion tissue culture model, the addition of complement (human serum) resulted in evidence of B-cell depletion consistent with what would be expected with posttransplant activation of bound Rituximab.InterpretationOur experiments illustrate the potential of EVLP as a platform to deliver monoclonal antibody therapies to treat donor lungs pretransplant with the goal of eliminating a latent virus responsible for considerable morbidity after lung transplantation.FundingSupported by the University Health Network Transplant Center.

Establishment of a Pig Influenza Challenge Model for Evaluation of Monoclonal Antibody Delivery Platforms.

mAbs are a possible adjunct to vaccination and drugs in treatment of influenza virus infection. However, questions remain whether small animal models accurately predict efficacy in humans. We have established the pig, a large natural host animal for influenza, with many physiological similarities to humans, as a robust model for testing mAbs. We show that a strongly neutralizing mAb (2-12C) against the hemagglutinin head administered prophylactically at 15 mg/kg reduced viral load and lung pathology after pandemic H1N1 influenza challenge. A lower dose of 1 mg/kg of 2-12C or a DNA plasmid-encoded version of 2-12C reduced pathology and viral load in the lungs but not viral shedding in nasal swabs. We propose that the pig influenza model will be useful for testing candidate mAbs and emerging delivery platforms prior to human trials.

Predicting bioavailability of monoclonal antibodies after subcutaneous administration: Open innovation challenge.

Despite the increasing trend towards subcutaneous delivery of monoclonal antibodies, factors influencing the subcutaneous bioavailability of these molecules remain poorly understood. To address critical knowledge gaps and issues during development of subcutaneous dosage forms for monoclonal antibodies, the Subcutaneous Drug Delivery and Development Consortium was convened in 2018 as a pre-competitive collaboration of recognized industry experts. One of the Consortium's eight problem statements highlights the challenges of predicting human bioavailability of subcutaneously administered monoclonal antibodies due to a lack of reliable in vitro and preclinical in vivo predictive models. In this paper, we assess the current landscape in subcutaneous bioavailability prediction for monoclonal antibodies and discuss the gaps and opportunities associated with bioavailability models for biotherapeutics. We also issue an open challenge to industry and academia, encouraging the development of reliable models to enable subcutaneous bioavailability prediction of therapeutic large molecules in humans and improve translation from preclinical species.

In vivo efficacy of bevacizumab-loaded albumin nanoparticles in the treatment of colorectal cancer.

Bevacizumab (as other monoclonal antibodies) has now become a mainstay in the treatment of several cancers in spite of some limitations, including poor tumour penetration and the development of resistance mechanisms. Its nanoencapsulation may be an adequate strategy to minimize these problems. The aim of this work was to evaluate the efficacy of bevacizumab-loaded nanoparticles (B-NP-PEG) on a xenograft model of human colorectal cancer. For this purpose, human serum albumin nanoparticles were prepared by coacervation, then coated with poly(ethylene glycol) and freeze-dried. B-NP-PEG displayed a mean size of about 300nm and a bevacizumab loading of approximately 145μg/mg. An in vivo study was conducted in the HT-29 xenograft model of colorectal cancer. Both, free and nanoencapsulated bevacizumab, induced a similar reduction in the tumour growth rate of about 50%, when compared to controls. By microPET imaging analysis, B-NP-PEG was found to be a more effective treatment in decreasing the glycolysis and metabolic tumour volume than free bevacizumab, suggesting higher efficacy. These results correlated well with the capability of B-NP-PEG to increase about fourfold the levels of intratumour bevacizumab, compared with the conventional formulation. In parallel, B-NP-PEG displayed six-times lower amounts of bevacizumab in blood than the aqueous formulation of the antibody, suggesting a lower incidence of potential undesirable side effects. In summary, albumin-based nanoparticles may be adequate carriers to promote the delivery of monoclonal antibodies (i.e. bevacizumab) to tumour tissues. Graphical abstract.

Human Plasma Protein Corona of Aβ Amyloid and Its Impact on Islet Amyloid Polypeptide Cross-Seeding.

Alzheimer's disease (AD) is the most severe form of neurological disorder, characterized by the presence of extracellular amyloid-β (Aβ) plaques and intracellular tau tangles. For decades, therapeutic strategies against the pathological symptoms of AD have often relied on the delivery of monoclonal antibodies to target specifically Aβ amyloid or oligomers, largely to no avail. Aβ can be traced in the brain as well as in cerebrospinal fluid and the circulation, giving rise to abundant opportunities to interact with their environmental proteins. Using liquid chromatography tandem-mass spectrometry, here we identified for the first time the protein coronae of the two major amyloid forms of Aβ-Aβ1-42 and Aβ1-40-exposed to human blood plasma. Out of the proteins identified in all groups, 58 proteins were unique to the Aβ1-42 samples and 31 proteins unique to the Aβ1-40 samples. Both fibrillar coronae consisted of proteins significant in complement activation, inflammation, and protein metabolic pathways involved in the pathology of AD. Structure-wise, the coronal proteins often possessed multidomains of high flexibility to maximize their association with the amyloid fibrils. The protein corona hindered recognition of Aβ1-42 fibrils by their structurally specific antibodies and accelerated the aggregation but not the β-cell toxicity of human islet amyloid polypeptide, the peptide associated with type 2 diabetes. This study highlights the importance of understanding the structural, functional, and pathological implications of the amyloid protein corona for the development of therapeutics against AD and a range of amyloid diseases.

Improving In Vivo Brain Delivery of Monoclonal Antibody Using Novel Cyclic Peptides.

Many proteins can be used to treat brain diseases; however, the presence of the blood–brain barrier (BBB) creates an obstacle to delivering them into the brain. Previously, various molecules were delivered through the paracellular pathway of the BBB via its modulation, using ADTC5 and HAV6 peptides. This study goal was to design new cyclic peptides with N-to-C terminal cyclization for better plasma stability and modulation of the BBB. Cyclic HAVN1 and HAVN2 peptides were derived from a linear HAV6 peptide. Linear and N-to-C terminal cyclic ADTHAV peptides were designed by combining the sequences of ADTC5 and HAV6. These novel cyclic peptides were used to deliver an IRdye800CW-labeled IgG monoclonal antibody into the brain. Cyclic HAVN1 and HAVN2 peptides deliver IgG into the brain, while the parent linear HAV6 peptide does not. Cyclic and linear ADTHAV and ADTC5 peptides enhanced brain delivery of IgG mAb, in which cyclic ADTHAV peptide was better than linear ADTHAV (p = 0.07). Cyclic ADTHAV and ADTC5 influenced the distribution of IgG mAb in other organs while HAV6, HAVN1 and HAVN2 did not. In summary, the novel cyclic peptides are generally better BBB modulators than their linear counterparts for delivering IgG mAb into the brain.