Protagonist Therapeutics, Inc

Protagonist Therapeutics, Inc. (referred to as Protagonist, the Company, we, our or us ) is an integrated discovery and development company with a validated technology platform. Our programs fall into three broad therapeutic areas: (i) inflammation and immunology ( I&I ), (ii) hematology and (iii) metabolic diseases. Our aim is to develop medicines for biologically and commercially validated targets which demonstrate a strong differentiation compared to existing therapies. Our Development Products and Discovery Programs Icotyde (icotrokinra) Icotyde (icotrokinra) is a first-in-class investigational targeted oral peptide that selectively blocks the Interleukin-23 receptor ( IL-23R ), which underpins the inflammatory response in psoriasis and offers potential in other IL-23-mediated diseases. Icotyde is licensed to Janssen Biotech, Inc., a Johnson & Johnson company ( JNJ ), under a license and collaboration agreement initially entered into in 2017. Following Icotyde’s joint discovery by Protagonist and JNJ scientists, pursuant to the license and collaboration agreement, we were primarily responsible for the development of Icotyde through Phase 1, with JNJ assuming responsibility for development in Phase 2 and beyond. In July 2025 and September 2025, respectively, JNJ submitted a New Drug Application ( NDA ) to the U.S. Food and Drug Administration ( FDA ) and an application to the European Medicines Agency ( EMA ) seeking the first approval of Icotyde for the treatment of adults and pediatric patients 12 years of age and older with moderate-to-severe plaque psoriasis.