T-cell-engaging bispecific antibodies (TCEs) that target tumor antigens and T cells have shown great promise in treating cancer, particularly in hematological indications. The clinical development of TCEs often involves a lengthy first-in-human (FIH) trial with many dose-escalation cohorts leading up to an early proof of concept (POC), enabling either a no-go decision or dose selection for further clinical development. Multiple factors related to the target, product, disease, and patient population influence the efficacy and safety of TCEs.
View Article and Find Full Text PDFIntroduction: Immunogenicity, the unwanted immune response triggered by therapeutic antibodies, poses significant challenges in biotherapeutic development. This response can lead to the production of anti-drug antibodies, potentially compromising the efficacy and safety of treatments. The internalization of therapeutic antibodies into dendritic cells (DCs) is a critical factor influencing immunogenicity.
View Article and Find Full Text PDFThe clinical use of therapeutic monoclonal antibodies (mAbs) for the treatment of cancer, inflammation, and other indications has been successfully established. A critical aspect of drug-antibody pharmacokinetics is immunogenicity, which triggers an immune response via an anti-drug antibody (ADA) and forms drug/ADA immune complexes (ICs). As a consequence, there may be a reduced efficacy upon neutralization by ADA or an accelerated drug clearance.
View Article and Find Full Text PDFAdvancing novel immunotherapy strategies requires refined tools in preclinical research to thoroughly assess drug targets, biodistribution, safety, and efficacy. Light sheet fluorescence microscopy (LSFM) offers unprecedented fast volumetric imaging of large tissue samples in high resolution. Yet, to date laborious and unstandardized tissue processing procedures have limited throughput and broader applications in immunological research.
View Article and Find Full Text PDFA relatively low clearance is one of the prominent favorable features of immunoglobulin G1-based therapeutic monoclonal antibodies (mAbs). Various studies have observed differential clearance of mAb glycoforms, including oligomannose glycoforms, which are considered a critical quality attribute because they show higher clearance than complex type glycoforms. Glycoform clearance, however, has not previously been studied after subcutaneous injection or in a porcine model system.
View Article and Find Full Text PDFMany in vitro and in vivo models are used in pharmacological research to evaluate the role of targeted proteins in a disease. Understanding the translational relevance and limitation of these models for analyzing a drug's disposition, pharmacokinetic/pharmacodynamic (PK/PD) profile, mechanism, and efficacy, is essential when selecting the most appropriate model of the disease of interest and predicting clinically efficacious doses of the investigational drug. Selected animal models used in ophthalmology, infectious diseases, oncology, autoimmune diseases, and neuroscience are reviewed here.
View Article and Find Full Text PDFThe occurrence of an immune response against therapeutic proteins poses a major risk for the development of biologics and for successful treatment of patients. Generation of anti-drug antibodies (ADAs) can lead to formation of immune complexes (ICs), consisting of drug and ADAs, with potential impact on safety, efficacy and exposure. Here, we focus on the effects of IC formation, i.
View Article and Find Full Text PDFPurpose: CD40 agonists hold great promise for cancer immunotherapy (CIT) as they enhance dendritic cell (DC) activation and concomitant tumor-specific T-cell priming. However, the broad expression of CD40 accounts for sink and side effects, hampering the efficacy of anti-CD40 antibodies. We hypothesized that these limitations can be overcome by selectively targeting CD40 agonism to the tumor.
View Article and Find Full Text PDFWhile free thiols in monoclonal antibodies (mAbs) have been extensively characterized by in vitro studies to probe its effect on antibody function and stability, their in vivo biotransformation has not been comprehensively studied. In this study, a panel of five recombinant IgG1 mAbs with elevated free thiols in the VH, VL, and CH2 domains were intravenously administered into Wistar rats. In vivo biotransformation of thirty-five free thiol sites in total (7 disulfide pairs in VL, CL, VH, CH1, HH, CH2, CH3 domains across the 5 mAbs) were monitored using a denaturing differential isotopic tagging procedure on immunopurified timepoints followed by LC-MS of tryptic digests.
View Article and Find Full Text PDFGood pharmacokinetic (PK) behavior is a key prerequisite for sufficient efficacy of therapeutic monoclonal antibodies (mAbs). Fc glycosylation is a critical quality attribute (CQA) of mAbs, due to its impact on stability and effector functions. However, the effects of various IgG Fc glycoforms on antibody PK remain unclear.
View Article and Find Full Text PDFWith the emergence of novel biotherapeutic formats and immunostimulatory biotherapeutics in cancer immunotherapy, an understanding of immune-complex (IC) mediated hypersensitivity reactions in toxicology studies - and their differentiation from pharmacology - remains key to the preclinical evaluation of these drugs. In this review we provide an in-depth evaluation and comparison of case examples where IC-mediated hypersensitivity reactions were observed in cynomolgus monkeys. We provide details of the parameters evaluated in each study to substantiate and guide the interpretation of these findings.
View Article and Find Full Text PDFMesothelin overexpression in lung adenocarcinomas correlates with the presence of activating KRAS mutations and poor prognosis. Hence SS1P, a mesothelin-targeted immunotoxin, could offer valuable treatment options for these patients, but its use in solid tumor therapy is hampered by high immunogenicity and non-specific toxicity. To overcome both obstacles we developed RG7787, a de-immunized cytotoxic fusion protein comprising a humanized SS1 Fab fragment and a truncated, B-cell epitope silenced, 24 kD fragment of Pseudomonas exotoxin A (PE24).
View Article and Find Full Text PDFIn this study, we show that liquid chromatography coupled with tandem mass spectrometry provides a sensitive, specific, and accurate absolute quantification of Erbitux, a human:murine chimeric mAb used for the treatment of colorectal cancer. Micrometric magnetized beads, functionalized with soluble epidermal growth factor receptor (sEGFR), the pharmacological target of Erbitux, were used for specific immunocapture of Erbitux allowing assessment of the antibody's biological potency and sample purification. Following digestion with trypsin, specific peptides from light and heavy chains were monitored in the selected reaction monitoring (SRM) mode.
View Article and Find Full Text PDFPersistent infection with human papillomaviruses (HPV) is a prerequisite for the development of cervical cancer. Vaccination with virus-like particles (VLP) has demonstrated efficacy in prophylaxis but lacks therapeutic potential. HPV16 L1E7 chimeric virus-like particles (CVLP) consist of a carboxy-terminally truncated HPV16L1 protein fused to the amino-terminal part of the HPV16 E7 protein and self-assemble by recombinant expression of the fusion protein.
View Article and Find Full Text PDFNV1020, an oncolytic herpes simplex virus type 1, can destroy colon cancer cells by selectively replicating within these cells, while sparing normal cells. NV1020 is currently under investigation in a clinical phase I/II trial as an agent for the treatment of colon cancer liver metastases, in combination with conventional chemotherapeutic agents such as 5-fluorouracil (5-FU), SN38 (the active metabolite of irinotecan), and oxaliplatin. To study the synergy of NV1020 and chemotherapy, cytotoxicity and viral replication were evaluated in vitro by treating various human and murine colon carcinoma cell lines, using a colorimetric viability assay, a clonogenic assay, and a plaque-forming assay.
View Article and Find Full Text PDFWe have recently demonstrated that immunization with hepatitis C virus-like particles (HCV-LPs) generated in insect cells can elicit both humoral and cellular immune responses in BALB/c mice. Here, we evaluate the immunogenicity of HCV-LPs in HLA2.1 transgenic (AAD) mice in comparison to DNA immunization.
View Article and Find Full Text PDF