FDA Approves Rusfertide for Polycythemia Vera

The FDA has approved rusfertide (Mimrylo) for adult patients with polycythemia vera (PV).¹

The approval is primarily supported by the phase 3 VERIFY study (NCT05210790) of patients with PV, in which 76.9% of patients receiving rusfertide required no phlebotomies between weeks 20 and 32 of the study compared with 32.9% of patients receiving placebo (P <.0001).¹

Key secondary end points were also met, with rusfertide providing hematocrit control under 45% in 62.6% of patients compared with 14.4% in the placebo arm (P <.0001). Notably, rusfertide treatment was also associated with a lower mean number of phlebotomies over weeks 0 to 32 vs placebo (0.5 vs 1.8, respectively; P <.0001).¹

Rusfertide is a first-in-class hepcidin mimetic that works to modulate iron availability and limit excessive red blood cell production, helping maintain hematocrit within the desired range. In patients with PV, keeping hematocrit below 45% is a key objective of treatment.²

Rusfertide has a manageable safety profile. According to the FDA, the most frequently occurring adverse reactions with rusfertide are injection site reactions and anemia.

“For patients living with PV, uncontrolled hematocrit can have serious consequences, including an elevated risk of life-threatening thrombotic events," Andrew T. Kuykendall, MD, VERIFY lead investigator and Associate Member in the Department of Hematology at Moffitt Cancer Center, stated in a news release.² “Current treatments, such as phlebotomy, leave a significant gap for too many patients and can pose challenges to daily life and routines. The approval of Mimrylo offers clinicians and patients a novel, first-in-class therapy that targets erythrocytosis, which drives excess red blood cell production in PV. The strength and consistency of the VERIFY data give me real confidence in [rusfertide’s] potential to advance how we treat PV in everyday practice and to maintain hematocrit control.”

VERIFY Study Design

The VERIFY study is a global, randomized, placebo-controlled study evaluating the efficacy and safety of rusfertide in 293 phlebotomy-dependent patients with PV over the course of 156 weeks. The primary end point of the trial is response during weeks 20 to 32, which is defined as the absence of phlebotomy eligibility.

The study is ongoing and consists of 3 parts:

1. Part 1A (weeks 0-32): Patients have been randomized 1:1 to receive either once-weekly subcutaneous injections of rusfertide (n = 147) or placebo (n = 146) in addition to standard of care. Dosing was titrated over the first 20 weeks, with the primary end point assessed from weeks 20 to 32.
2. Part 1B (weeks 32-52): Patients completing part 1A may roll over into an open-label portion (n = 274).
3. Part 2: An open-label, long-term safety assessment portion

“[Patients] living with polycythemia vera have long faced the challenge of managing a chronic blood disorder with frequent blood draws to help address the consequences of the red blood cell overproduction,” Tanya Wroblewski, MD, director of the Division of Nonmalignant Hematology within the FDA’s Center for Drug Evaluation and Research, stated in a news release.¹ “Today's approval of [rusfertide] offers a new, first-in-class option that has the potential to meaningfully reduce patient burden."

“People living with PV often experience complex and invisible symptoms, from extreme fatigue to the emotional strain of living with a chronic blood cancer,” added Kapila Viges, chief executive officer, MPN Research Foundation, in a news release.² “At the same time, we know that every patient’s experience with PV is different, underscoring the need to continue to listen closely to the community to understand what matters most. There remains a need for treatments that better address these daily challenges. This meaningful approval reflects important progress and brings forward a new treatment option in a disease where patients have long needed innovation and more choices. We are encouraged by [rusfertide’s] potential to help patients meet their treatment goals.”

REFERENCES

1. FDA Approves First Drug of Its Kind for Polycythemia Vera, a Rare Blood Disorder. Published online August 28, 2026. Accessed August 30, 2026. https://tinyurl.com/c56mh86y

2. Takeda Receives U.S. FDA Approval of MIMRYLO™ (rusfertide), Marking a Potential Shift in the Treatment Paradigm for Polycythemia Vera. August 28, 2026. Accessed August 30, 2026. https://tinyurl.com/3npdy39d