− Study met the primary endpoint, with a significantly higher proportion of clinical responders on rusfertide compared to placebo
− All four key secondary endpoints were met, including EU primary endpoint and patient-reported outcomes
− Rusfertide was generally well tolerated; no new safety findings were observed in the study
NEWARK, CA, USA & OSAKA, Japan & CAMBRIDGE, MA, USA I March 03, 2025 I Protagonist Therapeutics, Inc. (“Protagonist”) (NASDAQ:PTGX) and Takeda (TSE:4502/NYSE:TAK) today announced positive topline results for the Phase 3 VERIFY study, in which phlebotomy-dependent patients with polycythemia vera (PV) were randomized to treatment with either rusfertide or placebo, as an add-on to standard of care treatment. The study met its primary endpoint and all four key secondary endpoints. Rusfertide is a first-in-class investigational hepcidin mimetic peptide therapeutic, which has received Orphan Drug designation and Fast Track designation from the U.S. Food & Drug Administration (FDA).
Key findings from the study include:
- The primary endpoint of the study was met, with a significantly higher proportion of clinical responders1 among rusfertide-treated patients with PV (77%) compared to those who received placebo (33%) during weeks 20-32; p<0.0001. The primary endpoint of the study was the proportion of patients achieving a response, which was defined as the absence of phlebotomy eligibility.
- The first key secondary endpoint, which is the pre-specified primary endpoint for European Union (EU) regulators, was also met, with a mean of 0.5 phlebotomies per patient in the rusfertide arm compared to 1.8 phlebotomies per patient in the placebo arm during weeks 0-32; p<0.0001.
- The other three pre-specified key secondary endpoints, namely hematocrit control2 and patient-reported outcomes using PROMIS Fatigue SF-8a3 and MFSAF TSS-74, were also achieved with statistical significance.
- Rusfertide was generally well tolerated in the Phase 3 VERIFY trial, and safety was in line with previous rusfertide clinical studies. No new safety findings were observed in the study. The majority of adverse events were grade 1-2 injection site reactions and all serious adverse events reported were deemed to be not drug related. There was no evidence of an increased risk of cancer in rusfertide-treated patients compared to those on placebo.
“The positive results of the Phase 3 VERIFY study across the primary and all key secondary endpoints provide compelling evidence of the potential for rusfertide as a first-in-class erythrocytosis-specific agent to address unmet medical needs in patients with PV who are unable to achieve adequate hematocrit control despite standard of care treatments,” said Arturo Molina, M.D., M.S., Chief Medical Officer of Protagonist. “We plan to submit additional details of these promising results for presentation at upcoming medical conferences in 2025. We are immensely grateful to the patients, study staff and principal investigators who made the VERIFY study possible.”
Patients with PV are at increased risk for life-threatening cardiovascular and thrombotic events. Many patients with PV require regular phlebotomy, a process of removing blood to manage elevated hematocrit levels caused by an excess of red blood cells, as well as treatment with cytoreductive therapies. Phlebotomy can be burdensome and exacerbate symptoms, including severe fatigue, visual disturbances and iron deficiency, which impact patients’ quality of life. The reduction of hematocrit below 45% is a primary treatment goal for patients with PV as recommended by current treatment guidelines.
“We are encouraged by these results and excited about the potential of rusfertide to help patients living with PV. These patients may experience a high treatment burden, and severe symptoms can impact their quality of life,” said Andy Plump, M.D., Ph.D., President of R&D at Takeda. “We are deeply committed to bringing additional treatment options to those living with blood cancers, including myeloid cancers such as PV.”
“The totality of impressive clinical data to date shows that rusfertide has the potential for meaningful positive impact on the lives of patients with PV,” said Dinesh V. Patel, Ph.D., President and Chief Executive Officer at Protagonist. “We look forward to working with our partner, Takeda, to submit our findings to the regulatory agencies. Today’s study results also mark a critical inflection point in Protagonist’s decade long journey in the hepcidin program and further validates our platform and expertise in innovating highly differentiated peptide-based medicines to fulfill unmet medical needs.”
Under the license and collaboration agreement between Protagonist and Takeda, Protagonist earns a $25 million milestone payment following these positive results. The milestone is payable following completion of the VERIFY clinical study report.
The impact on Takeda’s financial results for the fiscal year ending March 31, 2025 (FY2024), following the study results, is immaterial.
Protagonist will host a conference call and webcast, for which details can be found below.
Protagonist Investor Conference Call and Webcast Details
The dial-in numbers for Protagonist’s investor update on Monday, March 3rd at 8:30 am ET are:
US-based Investors: 1-877-300-8521
International Investors: 1-412-317-6026
Conference Call ID: 1793905
The webcast link for the event can be found here: https://viavid.webcasts.com/starthere.jsp?ei=1708360&tp_key=94f2832555
A replay of the presentation will be available on the Protagonist Investor Relations Events and Presentations webpage following the event.
About VERIFY
The Phase 3 VERIFY trial (NCT05210790) is an ongoing, three-part, global, randomized, placebo-controlled trial evaluating rusfertide in 293 patients with polycythemia vera over a 156-week period. The trial is evaluating the efficacy and safety of once-weekly, subcutaneously self-administered rusfertide in patients with uncontrolled hematocrit who are phlebotomy dependent despite standard of care treatment, which could include hydroxyurea, interferon and/or ruxolitinib. The primary endpoint of the study was the proportion of patients achieving a response during weeks 20-32, which was defined as the absence of “phlebotomy eligibility.” To meet phlebotomy eligibility, patients in the study were required to have: confirmed hematocrit ≥45% that was ≥3% higher than their baseline hematocrit value, or hematocrit ≥48%.
All patients have completed their participation in the randomized, placebo-controlled portion of the trial evaluating the efficacy and safety of rusfertide plus current treatment versus placebo plus current treatment and are now in the open-label portions of the trial.
About Protagonist
Protagonist Therapeutics is a discovery through late-stage development biopharmaceutical company. Two novel peptides derived from Protagonist’s proprietary discovery platform are currently in advanced Phase 3 clinical development, with New Drug Application submissions to the FDA expected in 2025. Icotrokinra (formerly, JNJ-2113) is a first-in-class investigational targeted oral peptide that selectively blocks the Interleukin-23 receptor (“IL-23R”) which is licensed to JNJ Innovative Medicines (“JNJ”), formerly Janssen Biotech, Inc. Following icotrokinra’s joint discovery by Protagonist and JNJ scientists pursuant to the companies’ IL-23R collaboration, Protagonist was primarily responsible for development of icotrokinra through Phase 1, with JNJ assuming responsibility for development in Phase 2 and beyond. Rusfertide, a mimetic of the natural hormone hepcidin, is currently in Phase 3 development for the rare blood disorder polycythemia vera (PV). Rusfertide is being co-developed and will be co-commercialized with Takeda Pharmaceuticals pursuant to a worldwide collaboration and license agreement entered into in 2024 under which the Company remains primarily responsible for development through NDA filing. The Company also has a number of pre-clinical stage oral drug discovery programs addressing clinically and commercially validated targets, including IL-17 oral peptide antagonist PN-881, oral hepcidin program, and oral obesity program.
More information on Protagonist, its pipeline drug candidates and clinical studies can be found on the Company’s website at www.protagonist-inc.com.
About Takeda
Takeda is focused on creating better health for people and a brighter future for the world. We aim to discover and deliver life-transforming treatments in our core therapeutic and business areas, including gastrointestinal and inflammation, rare diseases, plasma-derived therapies, oncology, neuroscience and vaccines. Together with our partners, we aim to improve the patient experience and advance a new frontier of treatment options through our dynamic and diverse pipeline. As a leading values-based, R&D-driven biopharmaceutical company headquartered in Japan, we are guided by our commitment to patients, our people and the planet. Our employees in approximately 80 countries and regions are driven by our purpose and are grounded in the values that have defined us for more than two centuries. For more information, visit www.takeda.com.
1 A responder is a patient who completed weeks 0-32 of the study, was not phlebotomy eligible and did not receive a phlebotomy during weeks 20-32. To meet phlebotomy eligibility, patients in the study were required to have: confirmed hematocrit ≥45% that was ≥3% higher than their baseline hematocrit value, or hematocrit ≥48%. See “About VERIFY” section.
2 Proportion of patients with hematocrit less than 45%.
3 Mean change from baseline to week 32 using PROMIS Fatigue SF-8a, a questionnaire that measures patient-reported fatigue symptoms and their impact on daily life.
4 Mean change from baseline to week 32 using MFSAF TSS-7 v. 4.0, a questionnaire that measures patient reporting of seven key symptoms related to myelofibrosis (many of which are common among PV patients as well).
SOURCE: Takeda Pharmaceutical Co