•Systemic administration of cytokines for therapy is associated with severe dose-limiting toxicities.•Antibody-cytokine fusions localizing at sites of disease increase therapeutic index of cytokine ...payload.•Antibody format, target antigen and cytokine engineering impact on therapeutic performance of immunocytokines.
Antibody-cytokine fusion proteins represent a novel class of biopharmaceuticals, with the potential to increase the therapeutic index of cytokine ‘payloads’ and to promote leukocyte infiltration at the site of disease. In this review, we present a survey of immunocytokines that have been used in preclinical models of cancer and in clinical trials. In particular, we highlight how antibody format, choice of target antigen and cytokine engineering, as well as combination strategies, may have a profound impact on therapeutic performance. Moreover, by using anti-inflammatory cytokines, antibody fusion strategies can conveniently be employed for the treatment of auto-immune and chronic inflammatory conditions.
The advent of biologic therapies, particularly antibody therapeutics, has revolutionized the pharmacological treatment of many rheumatic diseases. Antibody discovery began with the immunization of ...mice for the production of rodent immunoglobulins, but advances in protein and genetic engineering have now made it possible to generate fully human antibodies, which are better tolerated by patients. For most clinical applications in rheumatology, antibodies have been used as blocking agents capable of neutralizing the function of pro-inflammatory proteins, such as TNF. The latest strategies involve antibody products armed with effector moieties, such as anti-inflammatory drugs or cytokines, or antibody products that are specific for multiple targets for the selective inhibition of inflammation at sites of disease. Antibodies are some of the best-selling drugs in the world, and with further advances in antibody development, engineering of armed antibodies and bispecific products will have an important role in the treatment of rheumatic diseases.
When delivered at a sufficient dose and dose rate to a neoplastic mass, radiation can kill tumor cells. Because cancer frequently presents as a disseminated disease, it is imperative to deliver ...cytotoxic radiation not only to the primary tumor but also to distant metastases, while reducing exposure of healthy organs as much as possible. Monoclonal antibodies and their fragments, labeled with therapeutic radionuclides, have been used for many years in the development of anticancer strategies, with the aim of concentrating radioactivity at the tumor site and sparing normal tissues. This review surveys important milestones in the development and clinical implementation of radioimmunotherapy and critically examines new trends for the antibody-mediated targeted delivery of radionuclides to sites of cancer.
We present the first direct comparative evaluation of an antibody–drug conjugate and of a small molecule–drug conjugate for cancer therapy, using chemically defined products which bind with ...high-affinity to carbonic anhydrase IX, a marker of tumor hypoxia and of renal cell carcinoma.
•Immunocytokines, a novel class of biopharmaceuticals against chronic inflammation.•Disease-homing activity combined with immunomodulatory properties of cytokines.•Basic principles in the design of ...immunocytokines.•Advanced products for chronic inflammation in preclinical and clinical development.
Antibody–cytokine fusion proteins, often referred to as immunocytokines, represent a novel class of biopharmaceutical agents that combine the disease-homing activity of certain antibodies with the immunomodulatory properties of cytokine payloads. Originally, immunocytokines were mainly developed for cancer therapy applications. More recently, however, the use of anti-inflammatory cytokines for the treatment of chronic inflammatory conditions and to treat autoimmune diseases has been considered. This review analyzes basic principles in the design of immunocytokines and describes the most advanced products in preclinical and clinical development.
The targeted delivery of potent cytotoxic agents has emerged as a promising strategy for the treatment of cancer and other serious conditions. Traditionally, antibodies against markers of disease ...have been used as drug‐delivery vehicles. More recently, lower molecular weight ligands have been proposed for the generation of a novel class of targeted cytotoxics with improved properties. Advances in this field crucially rely on efficient methods for the identification and optimization of organic molecules capable of high‐affinity binding and selective recognition of target proteins. The advent of DNA‐encoded chemical libraries allows the construction and screening of compound collections of unprecedented size. In this Review, we survey developments in the field of small ligand‐based targeted cytotoxics and show how innovative library technologies will help develop the drugs of the future.
On target: Antibodies have emerged as promising vehicles for the targeted delivery of potent cytotoxic agents to sites of disease. This Review surveys how the use of smaller organic molecules can yield targeted constructs with improved properties and how DNA‐encoded library technologies will facilitate the discovery of the necessary ligands (see scheme).
Engineered cytokine products represent a growing class of therapeutic proteins which need to be tested for biological activity at various stages of pharmaceutical development. In most cases, ...dedicated biological assays are established for different products, in a process that can be time-consuming and cumbersome. Here we describe the development and implementation of a universal cell-based reporter system for various classes of immunomodulatory proteins. The novel system capitalizes on the fact that the signaling of various types of pro-inflammatory agents (e.g., cytokines, chemokines, Toll-like receptor agonists) may involve transcriptional activation by NF-κB. Using viral transduction, we generated stably-transformed cell lines of B or T lymphocyte origin and compared the new reporter cell lines with conventional bioassays. The experimental findings with various interleukins and with members of the TNF superfamily revealed that the newly-developed "universal" bioassay method yielded bioactivity data which were comparable to the ones obtained with dedicated conventional methods. The engineered cell lines with reporters for NF-κB were tested with several antibody-cytokine fusions and may be generally useful for the characterization of novel immunomodulatory products. The newly developed methodology also revealed a mechanism for cytokine potentiation, based on the antibody-mediated clustering of TNF superfamily members on tumor-associated extracellular matrix components.
The CRISPR-Cas9 targeted nuclease technology allows the insertion of genetic modifications with single base-pair precision. The preference of mammalian cells to repair Cas9-induced DNA double-strand ...breaks via error-prone end-joining pathways rather than via homology-directed repair mechanisms, however, leads to relatively low rates of precise editing from donor DNA. Here we show that spatial and temporal co-localization of the donor template and Cas9 via covalent linkage increases the correction rates up to 24-fold, and demonstrate that the effect is mainly caused by an increase of donor template concentration in the nucleus. Enhanced correction rates were observed in multiple cell types and on different genomic loci, suggesting that covalently linking the donor template to the Cas9 complex provides advantages for clinical applications where high-fidelity repair is desired.
In nature, specific antibodies can be generated as a result of an adaptive selection and expansion of lymphocytes with suitable protein binding properties. We attempted to mimic antibody-antigen ...recognition by displaying multiple chemical diversity elements on a defined macrocyclic scaffold. Encoding of the displayed combinations was achieved using distinctive DNA tags, resulting in a library size of 35,393,112. Specific binders could be isolated against a variety of proteins, including carbonic anhydrase IX, horseradish peroxidase, tankyrase 1, human serum albumin, alpha-1 acid glycoprotein, calmodulin, prostate-specific antigen and tumour necrosis factor. Similar to antibodies, the encoded display of multiple chemical elements on a constant scaffold enabled practical applications, such as fluorescence microscopy procedures or the selective in vivo delivery of payloads to tumours. Furthermore, the versatile structure of the scaffold facilitated the generation of protein-specific chemical probes, as illustrated by photo-crosslinking.
Antibody–cytokine fusion proteins (immunocytokines) are innovative biopharmaceutical agents, which are being considered for the therapy of cancer and chronic inflammatory conditions. Immunomodulatory ...fusion proteins capable of selective localization at the sites of rheumatoid arthritis (RA) are of particular interest, as they may increase the therapeutic index of the cytokine payload. The F8 antibody recognizes the alternatively spliced extra domain A of fibronectin, a marker of angiogenesis, which is strongly overexpressed at sites of arthritis. In this study, we investigated the targeting and therapeutic activity of the immunocytokine F8-IL4 in the mouse model of collagen-induced arthritis. Different combination regimes were tested and evaluated by the analysis of serum and tissue cytokine levels. We show that F8-IL4 selectively localizes to neovascular structures at sites of rheumatoid arthritis in the mouse, leading to high local concentrations of IL4. When used in combination with dexamethasone, F8-IL4 was able to cure mice with established collagen-induced arthritis. Response to treatment was associated with an elevation of IL13 levels and decreased IL6 plasma concentrations. A fully human version of F8-IL4 is currently being developed for clinical investigations.
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