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Protagonist Therapeutics Initiates Phase 2b Study of Oral Drug Candidate PTG-100 in Ulcerative Colitis

MILPITAS, Calif., Jan. 17, 2017 /PRNewswire/ -- Protagonist Therapeutics, Inc. (NASDAQ: PTGX) today announced that it has initiated a global Phase 2b induction study in ulcerative colitis with PTG-100, an oral peptide that targets alpha4beta7 integrin. The aim of this randomized, double-blind, placebo-controlled, adaptive design study is to evaluate the safety/tolerability and efficacy of PTG-100 in approximately 240 adult ulcerative colitis patients with moderate to severe active disease.

"We are very pleased to advance our oral, alpha4beta7 integrin-specific antagonist peptide candidate, PTG-100, into this clinical proof-of-concept and dose optimization study," said Richard Shames, M.D., Chief Medical Officer at Protagonist. "We expect to complete the study and report top-line data in second half of 2018."

Patients will be randomized to one of four dose arms (150mg/300mg/900mg PTG-100 or placebo) for 12 weeks of once-daily oral dosing, followed by four weeks of safety follow-up. An interim futility analysis is expected to be performed in the second half of 2017, and if futility criteria are not met, one or two PTG-100 optimal doses will be selected for continued randomization of the remaining patients.

The primary efficacy endpoint of the study is clinical remission (as defined by rectal bleeding, stool frequency, and endoscopic subscores of the Mayo Score). Secondary endpoints include additional clinical and safety assessments, as well as pharmacokinetic, pharmacodynamic and other biomarker measurements of disease activity.

"PTG-100 is the most advanced asset to have emerged from our proprietary oral peptide technology platform that enables de novo discovery and optimization of novel peptides for protein:protein interaction (PPI) targets," said Dinesh Patel, Ph.D., Protagonist Therapeutics President and Chief Executive Officer. "Since these PPI targets have typically been approached by injectable antibody drugs, our platform offers the distinct advantage of generating oral therapeutic assets against the same PPI targets utilized by approved antibody drugs. We look forward to advancing PTG-100 to clinical proof-of-concept in patients with ulcerative colitis and applying our technology platform to discovering other novel peptidic assets to address unmet medical needs."  

Approximately 100 sites in the United States, Canada, Europe (Western, Central and Eastern), Asia, Australia, and New Zealand will participate in the study. For more information about the study, please visit

About PTG-100
PTG-100 is a potential first-in-class product candidate that is being developed initially for the potential treatment of moderate-to-severe active ulcerative colitis. Alpha4beta7 integrin is considered to be one of the most gastrointestinal-specific biological targets for inflammatory bowel disease due to its binding to MAdCAM-1, a cell membrane protein that resides mostly in the gastrointestinal (GI) vasculature.

About Protagonist Therapeutics
Protagonist Therapeutics is a clinical-stage biopharmaceutical company with a proprietary technology platform focused on discovering and developing peptide-based new chemical entities to address significant unmet medical needs. Its primary focus is on developing first-in-class oral peptide drugs that specifically target the same biological pathways for which there are marketed injectable antibody drugs. Compared to injectable antibody drugs, Protagonist's oral peptides offer preferential drug exposure in the GI tissue compartment, the potential for improved safety due to minimal exposure in the blood, improved convenience and compliance, and potentially an opportunity for the earlier introduction of targeted therapy for inflammatory bowel disease (IBD). Protagonist's oral peptide product candidates, PTG-100 and PTG-200, are based on this approach with the potential to transform the existing treatment paradigm for IBD, that includes both ulcerative colitis and Crohn's disease.

PTG-100, a potential first-in-class oral alpha4beta7 integrin antagonist is being developed initially for moderate-to-severe active ulcerative colitis. PTG-200, a potential first-in-class oral Interleukin-23 receptor antagonist is being developed initially for moderate-to-severe Crohn's disease and is currently in IND-enabling studies.

The company has a peptide technology platform that enables the discovery of oral and injectable peptides that can be utilized against a diverse set of targets and diseases including, but not confined to the GI. In addition to PTG-100 and PTG-200, the company is also engaged in the discovery and development of an injectable hepcidin mimetic, PTG-300, which is currently in IND-enabling studies. PTG-300 has potential utility for the treatment of iron overload disorders, such as beta-thalassemia and hereditary hemochromatosis, each of which may qualify PTG-300 for orphan drug designation.  

Protagonist is headquartered in Milpitas, California with its pre-clinical and clinical development 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 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," 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 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 inability to operate in a competitive industry and compete successfully against competitors that have greater resources than we do, our reliance on third parties, 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 quarterly report on Form 10-Q for the quarter ended September 30, 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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