ALX Oncology and Tallac Therapeutics Announce Collaboration on Novel Class of Cancer Immunotherapeutics

ALX Oncology Holdings Inc. a clinical-stage immuno-oncology company developing therapies that block the CD47 checkpoint pathway, and Tallac Therapeutics, Inc. (“Tallac”), a privately held biopharmaceutical company harnessing the power of innate and adaptive immunity to fight cancer, announced a collaboration to jointly develop, manufacture, and commercialize a novel class of cancer immunotherapeutics. Under the terms of the agreement, ALX Oncology and Tallac will share equally in the cost of research and development and any profits or losses incurred.

The collaboration builds on ALX Oncology’s expertise in developing therapies that block the CD47 checkpoint pathway and expands its immuno-oncology pipeline. The collaboration also extends Tallac’s pipeline of next generation immunotherapies derived from its novel Toll-like Receptor Agonist Antibody Conjugate (“TRAAC”) platform. The companies will leverage their respective scientific and technical expertise to advance an anti-SIRPα antibody conjugated to a Toll-like receptor 9 (“TLR9”) agonist for targeted activation of both the innate and adaptive immune systems.

“We are excited to partner with ALX Oncology in the development of next-generation breakthrough cancer immunotherapies,” said Hong I. Wan, Ph.D., President, Chief Executive Officer and co-founder of Tallac. “TLR9 agonists are a class of immunotherapy that generate both innate and adaptive immune responses which may produce robust and durable anti-cancer immunity for patients with advanced-stage cancers. While intratumoral TLR9 agonists have clinically validated this pathway, systemic administration has been unsuccessful, limiting clinical utility in broader patient populations. With Tallac’s TRAAC technology, we now have a way to target this pathway systemically, which could expand the clinical benefit to a much broader patient population. To date, we have generated promising preclinical data with multiple TRAAC molecules that demonstrates the potential of this pathway. The goal of our collaboration with ALX Oncology is to advance SIRPα TRAAC, a systemically delivered TLR9 agonist targeting dendritic cells via SIRPα receptors, enabling a powerful innate and adaptive anti-tumor immune response.”

“Collaborating with Tallac and their novel TRAAC platform broadens ALX Oncology’s therapeutic strategies to activate the innate immune system and SIRPα TRAAC complements our lead product candidate, ALX148,” said Jaume Pons, Ph.D., Founder, President and Chief Executive Officer of ALX Oncology. “While ALX148 is an antagonistic molecule designed to maximize the activity of a wide array of anticancer agents by the blockade of the CD47 myeloid checkpoint, SIRPα TRAAC is an agonistic molecule that directly activates dendritic cells and enables a coordinated innate and adaptive immune response against cancer. Since SIRPα is expressed on both dendritic cells and a range of tumor types, SIRPα TRAAC may enable an effective immune activation response in advanced cancer settings. We are excited about this potentially transformative approach and the possible benefits to patients that are in need of new treatment options.”