Abstract LB022: A novel first-in-class USP19 inhibitor for the treatment of cancer-induced muscle atrophy
Authors: Page Natalie , Karthikaisamy Vignesh , O'Hara Darren , Cranston Aaron N. , O'Dowd Colin R. , Jacq Xavier , Wilkinson Richard , Burton Stephanie , Gibson Hayley , Costa Joana , Longley Daniel , Helm Matthew , McGivern Chris , Shepherd Steven , Bell Christina , Hewitt Peter , McFarland Mary , Miel Hugues , Whitehead Steven , Proctor Lauren , Rountree Shane J. , Wappett Mark , Diaz Mauricio Berriel , Herzig Stephan , Harrison Timothy 
Published: April 2023

Abstract
Cancer cachexia is a metabolic wasting syndrome characterized by weight loss, anorexia and anemia as a result of tumor burden, and affects up to 80% of advanced cancer patients #1. Cachexia is particularly prevalent in pancreatic, lung, colorectal and gastro-intestinal cancers and can lead to reduced tolerance and responsiveness to chemotherapy, increased treatment-related toxicity and morbidity, and poor overall quality of life. There are currently no approved therapies for cancer cachexia.
The development and maintenance of muscle tissue is dependent on the balance between protein synthesis and protein degradation, controlled through various anabolic and catabolic signaling pathways. Dysregulation of these pathways can result in muscle atrophy, which arises in many chronic illnesses. The ubiquitin proteasome system (UPS) has a central role in regulating skeletal muscle physiology. Previous work utilizing USP19 knock out mouse models has demonstrated that USP19 plays an important role in muscle wasting and can protect against denervation-induced muscle atrophy #2.
We have previously demonstrated that inhibition of USP19 enzymatic activity spares the muscle wasting observed in limb-casted and denervated mouse models of muscle wasting. Here, we report the discovery of a novel, highly potent and selective inhibitor of USP19 (ADC-846) and demonstrate its utility in a cancer-induced muscle atrophy model in vivo. Pharmacological inhibition of USP19 by ADC-846 increased lean muscle and fat mass following oral dosing in a Lewis Lung Carcinoma-induced cachexia model and reduced the cachexic index by &gt;60% compared to controls. This data, in combination with our previous work detailing the effect of USP19 inhibition on muscle force and function, provides a much-needed novel pharmacological strategy for therapeutic intervention in muscle wasting conditions.
Citation Format: Natalie Page, Vignesh Karthikaisamy, Darren O'Hara, Aaron N. Cranston, Colin R. O'Dowd, Xavier Jacq, Richard Wilkinson, Stephanie Burton, Hayley Gibson, Joana Costa, Daniel Longley, Matthew Helm, Chris McGivern, Steven Shepherd, Christina Bell, Peter Hewitt, Mary McFarland, Hugues Miel, Steven Whitehead, Lauren Proctor, Shane J. Rountree, Mark Wappett, Mauricio Berriel Diaz, Stephan Herzig, Timothy Harrison. A novel first-in-class USP19 inhibitor for the treatment of cancer-induced muscle atrophy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB022.