CRS is one of the major safety liabilities associated with treatment with T cell engaging therapies in the clinic, including CAR T cells and T cell engagers. A series of in vitro and in vivo preclinical studies were conducted to gain a better understanding of the biological mechanisms inducing CRS, providing new avenues for the mitigation of the same.

This talk gives an overview of the identification and engineering of cattle-derived ultralong CDR-H3 antibodies. Specifically, a novel symmetric bispecific antibody format based on engraftments of cattle-derived knob paratopes onto peripheral loops of the IgG1 Fc region will be presented. For this, knob architectures were inserted into the AB loop or EF loop of the CH3 domain, enabling the generation of a novel symmetric bispecific antibody format.

This talk will describe albumin-based biomolecular designs utilising nucleic acid assemblies for incorporation of functionalised modules into bispecific T cell engagers. The inclusion of albumin sequences with different FcRn affinity used to tune pharmacokinetics and efficacy exhibited in double transgenic human albumin/human FcRn mouse models. A design for synergistic immuno-oncology biologic combinations will be presented.

To address chain pairing issues when expressing bispecific antibodies, we established a technology called FAST-Ig which promotes correct heavy- and light-chain assembly through electrostatic steering. Using NXT007 as an example, I will discuss critical factors like pairing potency, titre, physicochemical properties, and purification when applying FAST-Ig to clinical candidate antibodies. Additionally, I will introduce a next-generation T cell engager targeting CLDN6 that also utilises FAST-Ig.

Antibody-based immunotherapy is a promising strategy in cancer treatment. IgG eliminates tumor cells through NK cell-mediated ADCC and macrophage-mediated antibody-dependent phagocytosis. Neutrophils have been largely overlooked as potential effector cells, because IgG ineffectively recruits neutrophils. Bispecific antibodies, which potently activate neutrophils and induce migration through FcaRI have been developed. Coupling of cytokines or chemokines further recruits neutrophils as effector cells, which will be discussed.

We are at the dawn of a wave of TCR-based biologics and cell therapies recognising peptide-MHC, which expands oncology target opportunities beyond traditional mAb targets. I will provide an update on the development of T-Therapeutics’ OpTiMus platform which is a novel mouse transgenic platform for discovery of fully human therapeutic TCRs and bispecifics. It will cover an overview of our state-of-the art discovery process with data on our bispecific modality.

During this presentation, we'll delve into a groundbreaking PDAC treatment approach. Combining gemcitabine with the novel bispecific antibody scDb-hERG1-ß1, we validate its efficacy in vitro and in an orthotopic xenograft mouse model. We discuss enhanced cytotoxicity, reduced tumour masses, increased survival, and minimized toxicity. The scDb-hERG1-ß1 targets the hERG1/ß1 integrin complex, offering a promising therapeutic avenue for PDAC—leveraging low chemotherapy doses to mitigate side effects and resistance

Solid tumors have chemical and physical barriers that prevent the entry of antibody and cell therapies. TAVO306 is a cancer-associated fibroblast targeted enzyme, FAP x LRRC15 x hyaluronidase, that can disrupt the solid tumour stromal barrier. We show examples of triple negative breast cancer, pancreatic adenocarcinoma, gastric cancer, and small cell lung cancer that have the hyaluronan containing stromal barriers that are disrupted by the targeted hyaluronidase. The presence of FAP and LRRC15 can be confirmed also in several solid tumours by immunohistochemistry. The combination of TAVO306 with CD3 redirection molecules or TAVO412 have strong tumour growth inhibition profiles.

This presentation will discuss the development of a novel single-chain bispecific antibody, scDb-hERG1-β1, designed to target the hERG1 potassium channel and β1 integrin subunit. Demonstrating specificity for cancer cells, it effectively downregulates the hERG1/β1 complex, inhibits Akt phosphorylation, and reduces cell survival and migration. In vivo, scDb-hERG1-β1 exhibits promising pharmacokinetics, lacking general toxicity. This innovative antibody presents a potential therapeutic avenue for solid cancers overexpressing the hERG1/β1 integrin complex.

Immunotherapies based on the redirection of T cell activity toward tumour cells are actively being investigated. The impressive clinical success of bispecific T cell-engaging (TCE) antibodies and of engineered T cells expressing chimeric antigen receptors (CAR-T cells) in hematological malignancies, has led to renewed interest in a novel cancer immunotherapy strategy that combines features of antibody- and cell-based therapies. This emerging approach is based on the endogenous secretion of TCEs by engineered T cells (STAb-T cells). Adoptive transfer of genetically modified STAb-T cells has demonstrated potent anti-tumour activity in both solid tumour and hematologic preclinical models.

• Lead BsAb screening and optimizing binding affinity
• Leveraging computational tools
• Engineering for developability and optimal manufacturability
• Mitigating off-target effects

• Biology: Many major drivers of cancer are located within the cell
• Biology: Small molecule vs large molecule dilemma
• What drug delivery "vehicles" that can be employed to reach the tumor locale?
• What strategies can be employed to increase specific delivery to the target tissue?
• Enhancing cellular uptake and intracellular delivery: options
• What are some applications for intracellular targeting of therapeutics?

The eIg platform technology was used to generate a set of bispecific TCEs targeting EGFR and CD3. In total, eleven different TCE formats were analysed for binding to target and T cells, T cell-mediated killing of tumour cells, and for the activation of T cells. Our findings support that screening of a panel of formats is beneficial to identify the most potent bispecific TCE—and that format matters.

T cell-engaging bispecific antibodies (TCBs) targeting CD3 and tumour-specific antigens are very promising therapeutic modalities. New complex antibody formats harbor some analytical challenges that are ideally assessed by advanced and new developed methods. Here, we report a study to separate and identify critically modified proteoforms of TCBs using functional CD3 target affinity chromatography (AC) coupled with online mass spectrometry (MS).

While multispecific antibodies are a promising class of therapeutics entering clinical pipelines, they are inherently more complex in their design and generation. To that end, we describe a molecular toolkit for the robust generation of multispecific antibodies. The toolkit includes novel Fc and Fab pairing solutions, and versatile production and purification approaches. We demonstrate the broad applicability of our toolkit by interrogating a diverse panel of CD3- and CD28-containing multispecifics.

This presentation delves into the analysis of binary and ternary binding kinetics of multispecific antibodies using biosensors and cell-based approaches. Insights from this examination contribute to refining therapeutic strategies and optimising antibody design for enhanced efficacy in diverse biological contexts.