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Key Patent Issues Covering Protagonist Therapeutics' Oral Peptide IL-23 Receptor Antagonists, including the Development Candidate PTG-200

MILPITAS, Calif., May 4, 2017 /PRNewswire/ -- Protagonist Therapeutics, Inc. (NASDAQ: PTGX) today announced that a key patent has issued covering orally stable peptide inhibitors of the interleukin-23 receptor (IL-23R), including the company's clinical development candidate, PTG-200. The new U.S. patent, No. 9,624,268, provides composition of matter protection for PTG-200 and covers the use of the oral peptide inhibitors of IL-23R to treat inflammatory bowel diseases (IBD).

Protagonist Therapeutics, Inc. (PRNewsFoto/Protagonist Therapeutics, Inc.)

"This new patent provides intellectual property coverage until 2035 for our orally stable IL-23 receptor peptide inhibitors, including PTG-200," said David Liu, Ph.D., Protagonist's Chief Scientific Officer and Head of R&D. "Inhibition of the IL-23 pathway is an effective therapeutic treatment for IBD, as evidenced by a marketed injectable antibody drug for treatment of Crohn's disease. PTG-200 is an oral IL-23R antagonist and is designed to offer potential advantages such as improved convenience, patient compliance, safety, tolerability, and access to the targeted IL-23 receptors that are highly expressed in the gut associated lymphoid tissue. We are very enthusiastic about this novel targeted therapy for IBD and look forward to initiating human clinical trials with PTG-200 in the second half of this year."

About Protagonist Therapeutics

Protagonist Therapeutics is a clinical-stage biopharmaceutical company with a proprietary technology platform which is utilized to discover and develop novel peptide-based drugs to address significant unmet medical needs. Its primary focus is on developing first-in-class oral targeted therapy-based peptide drugs that work by blocking biological pathways that are currently targeted by marketed injectable antibody drugs. Protagonist's initial lead peptide product candidates, PTG-100 and PTG-200, are based on this approach, and the company believes these candidates have the potential to transform the existing treatment paradigm for inflammatory bowel disease (IBD), a set of gastrointestinal diseases consisting primarily of ulcerative colitis and Crohn's disease.

PTG-100, a potential first-in-class oral peptide alpha4beta7 integrin antagonist, is currently in Phase 2b clinical trials for moderate-to-severe ulcerative colitis.  PTG-200, a first-in-class oral Interleukin-23 receptor antagonist for potential treatment of Crohn's disease, is currently in pre-clinical development and is expected to enter Phase 1 clinical studies in the second half of 2017. 

In addition to PTG-100 and PTG-200, the company is developing an injectable hepcidin mimetic PTG-300 for potential development as an orphan drug to treat iron overload related rare diseases such as beta-thalassemia.  PTG-300 is currently in pre-clinical development and is expected to enter Phase 1 clinical studies in the second half of 2017.

Protagonist is headquartered in Milpitas, California with its pre-clinical and clinical staff in California, and discovery operations both in California and in Brisbane, Queensland, Australia. For further information, please visit

Cautionary Note on Forward-Looking Statements

This press release contains forward-looking statements for purposes of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include statements regarding our intentions or current expectations concerning, among other things, the potential for our programs, plans, timing and the availability of results of our clinical trials, enrollment in our clinical trials, capital resources, the possibility of obtaining orphan drug designation, and the potential for eventual regulatory approval of our product candidates. In some cases you can identify these statements by forward-looking words such as "may," "will," "continue," "expects," or the negative or plural of these words or similar expressions.  Forward-looking statements are not guarantees of future performance and are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated, including, but not limited to, our history of net operating losses, our reliance on third parties and uncertainty regarding our ability to achieve profitability, our ability to develop and commercialize our product candidates, our ability to use and expand our programs to build a pipeline of product candidates, our ability to obtain and maintain regulatory approval of our product candidates, our ability to operate in a competitive industry and compete successfully against competitors that have greater resources than we do,  and our ability to obtain and adequately protect intellectual property rights for our product candidates.  We discuss many of these risks in greater detail under the heading "Risk Factors" contained in our annual report on Form 10-K for the year ended December 31, 2016, filed with the Securities and Exchange Commission. Forward-looking statements are not guarantees of future performance, and our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate, may differ materially from the forward-looking statements contained in this press release. Any forward-looking statements that we make in this press release speak only as of the date of this press release. We assume no obligation to update our forward-looking statements whether as a result of new information, future events or otherwise, after the date of this press release.


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SOURCE Protagonist Therapeutics, Inc.

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