Protagonist Therapeutics, Inc. is a biopharmaceutical firm dedicated to discovering and advancing peptide-based therapies. Their research primarily focuses on treatments for hematological and blood conditions, as well as inflammatory and immune-mediated disorders. The company's pipeline features rusfertide (PTG-300), an injectable hepcidin mimetic currently undergoing Phase II clinical trials for the management of polycythemia vera, hereditary hemochromatosis, and other blood-related ailments. Also in Phase II development is PN-943, an oral peptide engineered as a specific antagonist of alpha-4-beta-7 integrin, intended for addressing inflammatory bowel disease (IBD). Furthermore, they are progressing PN-235, an orally administered antagonist specifically targeting the interleukin-23 receptor, designed for both IBD and various non-IBD therapeutic applications. Protagonist Therapeutics maintains a licensing and collaborative agreement with Janssen Biotech, Inc. Founded in 2006, the company's headquarters are located in Newark, California.