Eliminating extracellular proteins is a compelling therapeutic modality. EpiTACs are bispecific antibodies where one arm binds a target and the other arm leverages an EpiAtlas of tissue-enriched degrading receptors comprised of transmembrane ligases, cytokine/chemokine receptors, and internalizing receptors resulting in selective degradation of membrane and soluble proteins. EpiTACs elicit robust in vitro and in vivo activity in a target-, tissue- and disease-specific manner for a broad range of indications. Compelling data across multiple targets demonstrates that EpiTACs can degrade a target independent of mutational status, are better than neutralizing antibodies in preclinical models, and drive a survival benefit in preclinical tumor models.

Targeted protein degradation (TPD) using proteolysis-targeting chimeras (PROTACs) and molecular glue degraders (MGDs) is an emerging strategy to develop novel therapies for cancer and beyond. A key challenge in TPD is the limited availability of ligandable E3 ligases, with current studies mainly using CRBN and VHL. The TPD community aims to expand the E3 ligase landscape. Here, we offer a versatile toolbox for developing new E3 ligase-based degraders.

E3 ubiquitin ligases are master regulators of protein homeostasis, orchestrating diverse cellular processes. Despite their critical role, our understanding of the E3 ligase landscape remains limited. This talk will present our efforts in identifying and characterizing novel E3 ligases using cutting-edge proteomic and biochemical approaches. By elucidating the substrate specificity and regulatory mechanisms of these enzymes, we aim to uncover new therapeutic opportunities for diseases driven by protein dysfunction.

• Protein design and degrader selection strategies to enhance tissue selectivity
• Antibody developability assessments to ensure specificity and drug-like properties
• Multispecific protein production and purification from screening through manufacturing​

This study explores the potential of targeted protein degradation (TPD) systems to enhance Wnt signaling. A novel fusion protein, SWEETS, was engineered to selectively degrade E3 ubiquitin ligases, leading to increased Wnt activity. This approach demonstrates the feasibility of tissue-specific modulation of Wnt signaling, opening up possibilities for new therapeutic strategies.

In the quest for effective and safe PROTAC therapeutics for presently incurable diseases, conventional reductionist approach often falls short due to its inability to fully capture the complexity of human pathology. We propose a paradigm shift towards a systems pharmacology, leveraging the rich data from patient and perturbation omics. Our recent efforts include 1) predicting genome-wide PRTOAC targets, 2) cell type-specific phenotype compound screening, and 3) transfer learning to bridge disease models and human physiology. Put together, the AI-powered systems pharmacology approach has been successfully applied to personalized Alzheimer’s disease drug repurposing, opioid use disorder drug discovery, and cancer polypharmacology.

We engineered LOVdeg, a light-responsive protein tag that can be appended to a protein of interest for inducible degradation in Escherichia coli using blue light. We demonstrate the modularity of LOVdeg and pair it with other optogenetic systems for enhanced performance. Our results introduce a valuable tool for bacterial synthetic biology and exemplify the design of a dynamic degradation tag that interfaces with endogenous proteasome machinery.

Extracellular targeted protein degradation (eTPD) is making rapid strides in targeting disease-associated proteins that are otherwise insufficiently inhibited by conventional drugs. We developed CYpHER, a catalytic eTPD technology that uses pH-engineered molecules that bind both target and transferrin receptor (TfR), driving target uptake and endosomal release. TfR also permits CNS access, and we are developing potent, durable molecules for targeting neurological conditions poorly served by existing strategies.

Synucleinopathies and tauopathies, characterized by a-synuclein or tau protein accumulation, lack effective treatments. Antibody therapies targeting these proteins aim to inhibit aggregation and enhance degradation, but face various challenges. Leveraging protein degradation technologies, we developed single-domain antibody-based degraders with excellent brain and neuronal uptake as well as improved capacity for a-synuclein or tau degradation, by increasing their proteasomal or lysosomal degradation. These strategies hold promise for treating synucleinopathies and tauopathies.

The Jian Jin Laboratory at Icahn School of Medicine at Mount Sinai is a leader in discovering novel degraders targeting oncogenic proteins and developing new technologies for advancing the targeted protein degradation field. Our lab’s progress in recent years advancing the targeted protein degradation and stabilization, exemplified by Bridged PROTACs, TF-PROTACs, TeloTAC, Methyl-PROTAC, Z-PROTAC, and KEAP1-recruiting PROTACs, as well as additional approaches, will be discussed.

Our group at AbbVie has joined forces with BioAnalysis, LLC to develop a powerful new platform assay that utilizes analytical ultracentrifugation to probe degrader-induced ternary complex formation more deeply, while addressing knowledge gaps in ternary complexes. We hope to share practical applications of this method/case studies with an audience that is interested in targeted protein degradation and next-generation degradation.

Plexium harnesses a differentiated platform of proprietary technologies and approaches to establish a robust and diverse portfolio of monovalent targeted protein degrader therapeutics. Our cell-based uHTS platform leverages multiple assay formats including reporter, multiplexed immunofluorescence, transcriptomic, and phenotypic readouts resulting in identification of novel monovalent degraders, neosubstrates, and unprecedented E3 ligases. Microfluidic bead-based DNA encoded libraries enables interrogation of chemical space with advanced assays at a scale not otherwise practical.

Developing robust assays for protein degradation studies is crucial for advancing drug discovery and understanding cellular mechanisms. This work focuses on designing reliable, sensitive, and high-throughput assays to monitor protein degradation dynamics. By integrating advanced detection methods and optimizing assay conditions, these tools enable precise quantification of degradation rates, contributing to the evaluation of therapeutic candidates and enhancing our knowledge of proteostasis regulation in health and disease.