Peptide · Fact sheet
Rusfertide
Also known as PTG-300 · Mimrylo
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.
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.
Benefits people look for
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.
What the evidence supports
- 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.
All research areas
- Polycythemia vera
- Hematocrit control
- Reducing phlebotomy burden
- Symptoms related to polycythemia vera
- Other populations and outcomes outside the approved product scope
Anecdotal reports & lived experiences
Reports describe what someone noticed. They cannot establish cause, typical results, or how often a side effect happens.
No attributable personal reports are summarized here yet. The benefits above describe research interests; the side effects below come from the cited medical sources.
We do not fill this gap with unsourced testimonials or estimated success rates.
Side effects & risks
- The FDA label warns of new or worsening thrombocytosis (a high platelet count), injection-site reactions, and possible fetal harm based on animal studies.
- Injection-site reactions and anemia were the most common adverse reactions in the approval study. Blood-count changes are relevant to this iron-regulating treatment.
- The label does not establish pediatric safety and effectiveness, and advises against breastfeeding during treatment because of possible serious effects on the child.
This is a summary of the cited evidence, not a complete product label. A lack of human safety data does not establish safety.
Clinical research: how strong is it?
Moderate human evidenceFDA 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.
Selected research to read
Official record for the 293-participant pivotal trial, including endpoints and public results status.
Peer-reviewed Phase 2 evidence for hematocrit control and phlebotomy reduction.
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
FDA approval & research 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.
Approved uses covered here
- Treatment of erythrocytosis in adults with polycythemia vera under the Mimrylo approval
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 we still don’t 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
The 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.
Sources & further reading
Medical evidence and regulatory sources are listed here. Personal reports are linked separately in the experiences section.
- 1fdaFDA: Mimrylo prescribing information
August 2026 label: indication, platelet-count warning, injection-site reactions, anemia and reproductive risks.
- 2fdaFDA: Mimrylo approval for polycythemia vera
Product-specific approval decision and pivotal-trial summary.
- 3fdaFDA novel drug approvals: Mimrylo
FDA identifies the approved use as erythrocytosis in adults with polycythemia vera.
- 4clinical trialsClinicalTrials.gov: VERIFY Phase 3 trial
Official record for the 293-participant pivotal trial, including endpoints and public results status.
- 5pubmedREVIVE randomized-withdrawal trial
Peer-reviewed Phase 2 evidence for hematocrit control and phlebotomy reduction.
- 6company releaseTakeda: FDA accepts rusfertide application
Company-reported application acceptance and priority-review milestone; not an FDA approval decision.
- 7educationalSEC filing: rusfertide regulatory status
Public company filing confirming submission and pending review of the application.