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Protagonist Therapeutics Protagonist Reports First Quarter 2021 Financial Results and Provides Corporate Update May 4 , 2021 NEWARK , Calif . , May 4 , 2021 / PRNewswire / -- Protagonist Therapeutics ( Nasdaq : PTGX ) ( " Protagonist " or the " Company " ) today reported financial results for the first quarter of 2021 ended March 31 , 2021 and provided a corporate update . " Our progress this quarter affirms the strength of our pipeline and execution capabilities , " said Dinesh Patel , PhD , Protagonist's President and Chief Executive Officer . " For our lead drug candidate , rusfertide in polycythemia vera , we have completed enrollment for our Phase 2 study and confirmed the registrational path forward based on recent engagement with both U.S. and European regulators . We look forward to providing an interim update from our ongoing Phase 2 study at a major medical conference in the second quarter of 2021. " Dr. Patel continued , " We are very pleased with the rate of enrollment in our ongoing Phase 2 study of the oral alpha - 4 - beta- 7 - integrin antagonist PN - 943 . For our oral IL - 23 receptor antagonists , we expect to dose the first subject in the Phase 1 study of PN - 232 in the second quarter of 2021 and intend to complete both this trial and the Phase 1 trial of PN - 235 during the second half of 2021. There is excellent movement forward across our full portfolio , driven by our commitment to patients in need of new and better therapeutic options . " PRODUCT DEVELOPMENT AND CORPORATE UPDATE Disorders of Red Blood Cells and Iron Regulation Rusfertide ( PTG - 300 ) Investigational , injectable , hepcidin mimetic discovered through our peptide technology platform . Hepcidin is a natural hormone that regulates iron homeostasis and controls the absorption , storage , and distribution of iron in the body . Rusfertide is currently being evaluated for disorders associated with iron overload and excessive erythrocytosis ( red blood cell production ) . • In March 2021 , following an end - of - Phase 2 meeting with the U.S. Food and Drug Administration ( " FDA " ) and written comments from the European Medicines Agency ( " EMA " ) , Protagonist has advanced its preparations for a global pivotal study of rusfertide in polycythemia vera ( " PV " ) . The Company plans to initiate this Phase 3 study in early 2022 . • In April 2021 , Protagonist announced completion of enrollment in the ongoing Phase 2 study of rusfertide in PV . The Company plans to present updated interim data from this study at an upcoming medical meeting in the second quarter of 2021 . • In the second half of 2021 , Protagonist expects to announce preliminary results from the ongoing Phase 2 open - label proof - of - concept study of rusfertide in patients with hereditary hemochromatosis ( " HH " ) . • In addition to ongoing studies in PV and HH , the Company expects to select a third indication for rusfertide in 2021 . Inflammatory Bowel Diseases PN - 943 Investigational , orally delivered , gut - restricted alpha - 4 - beta - 7 specific integrin antagonist for inflammatory bowel diseases . • The 150 - patient Phase 2 " IDEAL " study evaluating the safety , tolerability and efficacy of PN - 943 in patients with moderate to severe ulcerative colitis is underway , and the study is on track for completion in 2022 . Oral IL - 23 Receptor Antagonists PTG - 200 ; PN - 235 ; PN - 232 ( Janssen collaboration ) Investigational , orally delivered , IL - 23 receptor antagonists . Protagonist has entered into a worldwide agreement with Janssen to co - develop and commercialize these drug candidates . • In the second quarter of 2021 , Protagonist expects to dose the first subject in the Phase 1 study of PN - 232 . The Company expects to complete both this trial and the Phase 1 trial of PN - 235 in the second half of 2021. PN - 232 and PN - 235 are part of the oral IL - 23 pathway blocker portfolio strategy , pursued in collaboration with Janssen . • Enrollment continues for the Phase 2a proof - of - concept PRISM study of PTG - 200 , a first - generation drug candidate for patients with moderate to severe Crohn's disease . First Quarter 2021 Financial Results