Plain-English fact sheet
Rusfertide
Also known as PTG-300, Mimrylo
Rusfertide is the active ingredient in Mimrylo, an FDA-approved medicine for erythrocytosis in adults with polycythemia vera.
Quick answer
FDA approved Mimrylo (rusfertide) for erythrocytosis in adults with polycythemia vera. Approval is specific to that product and population; it does not establish general iron-management or wellness uses.
Published by PeptideFactSheets. Sources and methods · Research reporting, not clinical review.
What is Rusfertide?
Rusfertide is a manufactured peptide that mimics hepcidin, the hormone that regulates iron availability.
By restricting iron available for red-blood-cell production, it is designed to help control hematocrit and reduce the need for phlebotomy in polycythemia vera.
What do the human studies show?
Selected research questions, not a complete inventory of indications or trials. Source checking is not independent clinical review. How we read the evidence.
For this question, the FDA decision below is the main source. It explains the evidence behind the approval and its limits.
What these results can and cannot tell us
Is the rusfertide FDA application still pending?
FDA approved Mimrylo; earlier pending-review language is superseded.
Limit: An approval announcement does not establish every long-term outcome or constitute a complete safety review.
Check the sources: FDA Mimrylo approval (checked 2026-09-18)
What is approved, and for whom?
United States records selected for the questions above; not a complete label or a worldwide approval inventory.
Mimrylo: Polycythemia vera
Subcutaneous injection · Adults with polycythemia vera
approved — Approval does not establish other iron-related or wellness uses. The announcement is not a complete safety label.
Exact linked source and stated indication only; not an exhaustive regulatory search.
Read the original source · Source checked: 2026-09-18 · Decision: 2026-08-28
Compare research questions · Submit a source-based correction
Why are people interested in it?
It applies peptide design to iron regulation and red-blood-cell production in a defined blood disorder.
An approval decision is distinct from evidence about long-term thrombosis, disease progression or survival.
Current regulatory status
FDA approved Mimrylo for erythrocytosis in adults with polycythemia vera. Earlier application-acceptance and priority-review records are historical milestones, superseded by the approval decision.
What is it approved for?
- Treatment of erythrocytosis in adults with polycythemia vera under the Mimrylo approval
Approval and research context
Mimrylo approved for a defined adult blood disorder
FDA approved Mimrylo (rusfertide) for erythrocytosis in adults with polycythemia vera. Earlier priority-review records are historical and no longer describe a pending decision.
This summarizes the cited product or research record. Trial phases do not establish successful completion of earlier stages, and a stopped program is not ongoing development. Approval applies only to the labeled product, use and population.
What is it being studied for?
Investigational areas
- Other populations and outcomes outside the approved product scope
Evidence snapshot
FDA reports that the 293-participant randomized Phase 3 VERIFY trial supported approval. The measured phlebotomy outcome should not be substituted for evidence of longer survival or prevention of thrombosis.
Potential benefits being researched
- The Phase 2 REVIVE trial found better composite response during randomized withdrawal with rusfertide than placebo.
- FDA reports that the pivotal trial found fewer patients meeting phlebotomy criteria with Mimrylo than placebo.
Potential does not mean proven. Study design, population, endpoint, and regulatory review matter.
Known or possible risks
- Published and sponsor-reported studies identify injection-site reactions, anemia, and fatigue among observed adverse events.
- Changing iron availability can produce iron-related and blood-count effects that require study-specific clinical monitoring.
- The FDA approval announcement identifies injection-site reactions and anemia as the most common adverse reactions; that short announcement is not a complete prescribing-information safety review.
What we still do not know
- The full long-term safety profile with broader clinical exposure
- Long-term effects on thrombosis, disease progression, symptoms, and survival
- Uncommon harms with broader exposure
- How it compares with established polycythemia vera strategies on patient-centered outcomes
Plain-English takeaway
Rusfertide has a product-specific FDA approval for adults with polycythemia vera. Evidence for reduced phlebotomy requirements does not answer every question about long-term patient outcomes.
Research and reference links
Use these primary and reputable sources to verify status and read beyond this summary. Trial registries may list studies without proving a benefit.
- 1fdaFDA: Mimrylo approval for polycythemia vera
Product-specific approval decision and pivotal-trial summary.
- 2fdaFDA novel drug approvals: Mimrylo
FDA identifies the approved use as erythrocytosis in adults with polycythemia vera.
- 3clinical trialsClinicalTrials.gov: VERIFY Phase 3 trial
Official record for the 293-participant pivotal trial, including endpoints and public results status.
- 4pubmedREVIVE randomized-withdrawal trial
Peer-reviewed Phase 2 evidence for hematocrit control and phlebotomy reduction.
- 5company releaseTakeda: FDA accepts rusfertide application
Company-reported application acceptance and priority-review milestone; not an FDA approval decision.
- 6educationalSEC filing: rusfertide regulatory status
Public company filing confirming submission and pending review of the application.