Venom derived cysteine-rich miniproteins (knottins) have potential as therapeutic agents to block ion channels but suffer from manufacturing difficulties, short half-lives and a lack of specificity. Maxion have developed a novel molecular format wherein the knottin replaces a peripheral CDR loop of an antibody. This format (termed KnotBody^TM), combines the best features of both molecular classes. The presentation illustrates the generation of KnotBody inhibitors of multiple ion channels and their optimisation using phage and mammalian display.

We have generated a novel library approach for high-throughput de novo identification of humanized single-domain antibodies following camelid immunization. We demonstrate that by exploiting this approach, humanized high-affinity sdAbs with an optimized in silico developability profile can be generated that display favorable biophysical, biochemical, and functional attributes and do not require any further sequence optimization.

Immune cell-engaging and activating drugs show great value for patients, and have pathed the way for a next-generation of molecules optimized for depth and duration of response. For the most potent of these molecules, disease-restricted activation will be a key requirement to enable safe and efficacious dosing. Based on our DARPin (Designed Ankyrin Repeat Protein) modality, we have built various such design approaches. We will present an update on our tumor-activated FAPxCD40 program (MP0317), and introduce a novel SWITCH-DARPin approach, allowing disease-restricted activation based exclusively on the binding of tumor targets in the diseased area.

ALG.APV-527 was generated by incorporating binders obtained from the Alligator GOLD library into Aptevos ADAPTIR format, and was designed for 5T4-conditional 4-1BB-mediated anti-tumor activity. Preclinical in vitro and in vivo models demonstrate potential to minimize systemic immune activation and hepatotoxicity, while providing efficacious tumor-specific responses. ALG.APV-527 has potential as a promising anti-cancer therapeutic for the treatment of 5T4-expressing tumors and is currently evaluated in a Phase 1 study.

We generated a platform for the discovery of antibodies by chicken immunization, followed by transfer of antibody diversity, to yeast for surface display screening (YSD). Antibodies with broad epitope coverage are obtained. Common light chain antibodies can be isolated for modular assembly of multi-specifics. CDR transplantation to a human framework with partial randomization of signature residues, followed by YSD screening of high-affinity variants, allows for straightforward humanization.

Mammalian display libraries can be interrogated consecutively for manufacturability and specificity. Pre-enriched libraries secreting antibodies are a perfect match for microfluidics-assisted high-throughput screening. Options for (and recent advances in) combining these emerging technologies will be discussed.

Antibody discovery against ion channels, GPCRs, and SLC transporters is very challenging. Failing drug campaigns, leading to non-developable antibodies, are often associated with display technology unfit for low target stability, and uncontrolled selection conditions. Here, case studies using the Linkster discovery platform demonstrate that developable and highly stable, conformation-specific antibody starting points can be reliably generated within 3 weeks, through smart library design (here in the form of optimised synthetic VHH libraries) and novel selection and screening technology.

Synthetic antibody libraries were designed featuring ShK, a natural peptide that is a potent modulator of the ion channel Kv1.3, as the CDRH3 region of a cow VH domain. ShK sequence variants were engineered to enhance specificity for Kv1.3 over Kv1.1. Library hits were evaluated for activity and specificity in high-throughput e-phys studies, and compared to mAbs from naïve and immunized cow antibody libraries, and from engineered chickens producing human sequence antibodies.

CAR T cell products have entered mainstream therapy of leukemias. To further build on these real-world successes, and to expand adoptive therapy to solid tumors, there is a need for tumor-selective targets, as well as strategies to create or retrieve receptors that recognize such targets. In this presentation, the selection and validation of targets, and more specifically, corresponding receptors is highlighted- including TCR-like antibodies, as well as TCRs directed against cancer-selective peptide: MHCs. Besides the translational route, the introduction of such receptors in Phase I trials and their future outlook is discussed.