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Protagonist Therapeutics Announces U.S. FDA Approval of Hepcidin Mimetic Peptide MIMRYLO ( TM ) ( rusfertide ) for Polycythemia Vera MIMRYLO ™ is the First and Only Hepcidin Mimetic Peptide Therapy Approved for the Treatment of Erythrocytosis in Adults with Polycythemia Vera , Offering a Novel Mechanism to Maintain Hematocrit Control , Meaningfully Reduce Phlebotomy Burden , and Improve Fatigue Approval Supported by Phase 3 VERIFY Results Showing 76.9 % of Patients Achieved Response During Weeks 20-32 FDA Approval Triggers $ 275M in Milestones , 14 % -29 % Royalties , with Up to an Additional $ 875M in Potential Future Milestones Investor call to be held Monday , August 31st at 8:30 am ET NEWARK , CA / ACCESS Newswire / August 28 , 2026 / Protagonist Therapeutics , Inc. ( NASDAQ : PTGX ) ( " Protagonist " or " the Company " ) announced today that Takeda received U.S. Food and Drug Administration ( FDA ) approval for MIMRYLO ( rusfertide ) , a subcutaneously delivered first - in - class hepcidin mimetic peptide for the treatment of erythrocytosis in adults with polycythemia vera ( PV ) . MIMRYLO is the first and only hepcidin mimetic approved for polycythemia vera ( PV ) , a blood cancer characterized by excessive production of red blood cells . " Today's FDA approval of MIMRYLO represents a paradigm shifting approach to management of PV . MIMRYLO mimics the action of hepcidin , the body's natural master regulator of iron availability thereby controlling hematocrit levels and helping restore iron balance . MIMRYLO was conceived fourteen years ago with the idea that a mimetic of hepcidin , the body's primary regulator of iron homeostasis , could address the underlying biology of erythrocytosis in PV . The approved label also reflects improvement in fatigue as measured by PROMIS Fatigue Short Form 8a . " said Dinesh V. Patel , PhD , President and Chief Executive Officer of Protagonist Therapeutics . " I am very proud of what the team at Protagonist , in partnership with investigators and patients , have accomplished in bringing this drug over the finish line , and we have full confidence in Takeda as the ideal partner to bring MIMRYLO to patients who need it most . " " This is Protagonist's second FDA approval in 2026 , reflecting years of disciplined investment in the right type of innovative projects , and working with the right partners at the right time , " Patel continued . " With two approved products validating our peptide - centric drug discovery and development acumen and a strong financial foundation , the Company is now focused on leveraging its expertise to advance the next generation of wholly owned product candidates in IL - 17 , obesity , and beyond with the intent of addressing unmet needs of patients and creating long- term value for our shareholders . " MIMRYLO will be commercialized by Takeda under the worldwide license and collaboration agreement entered into in 2024 between Protagonist and Takeda . Protagonist discovered rusfertide ( PTG - 300 ) and had primary responsibility for its development through Phase 3 , with Takeda assuming responsibility for NDA submission and commercialization following Protagonist's opt - out election in April 2026 . FDA approval of MIMRYLO triggers $ 275 million in payments to Protagonist , consisting of a $ 200 million opt - out fee and a separate $ 75 million approval milestone . Protagonist is eligible to receive up to an additional $ 875 million in total potential milestone payments , as well as tiered royalties ranging from 14 % to 29 % on worldwide net sales , corresponding to approximately 21 % on a weighted - average basis at $ 1.5 billion in annual sales . Clinical evidence summary MIMRYLO was approved on the basis of the Phase 3 VERIFY study , a randomized , double - blind , placebo - controlled trial in patients with polycythemia vera . In VERIFY , patients in the MIMRYLO arm achieved statistically significant benefit over the placebo arm , including the proportion of responders ( with absence of phlebotomy eligibility ) , mean number of phlebotomies , proportion of participants maintaining hematocrit < 45 % , and mean change from baseline