FDA approves Mimrylo for adults with polycythemia vera

The Food and Drug Administration has approved Mimrylo (rusfertide) for adults with polycythemia vera, a rare blood disorder that causes the body to make too many red blood cells.

The agency said the treatment is for patients whose disease has not been adequately controlled with existing therapies. Polycythemia vera can thicken the blood and raise the risk of blood clots, stroke and heart attack, according to the FDA.

Approval

The FDA said Mimrylo is the first approved treatment for polycythemia vera that mimics hepcidin, a hormone that helps regulate iron. By limiting iron available for new red blood cells, the drug is intended to help keep red blood cell levels under control.

One treatment goal for polycythemia vera is keeping hematocrit below 45%, the FDA said. That often requires phlebotomy, a procedure that removes blood from a vein. Some patients still need frequent phlebotomies even while on standard treatment.

Trial results

The FDA said it based the approval on the VERIFY trial, a multicenter, randomized, double-blind, placebo-controlled phase 3 study of 293 adults with polycythemia vera who needed frequent phlebotomies despite standard-of-care therapy.

Participants were assigned 1:1 to Mimrylo or placebo for 32 weeks. Treatment started at 19 mg once weekly by subcutaneous injection and was adjusted to keep hematocrit below 45%.

According to the FDA, 76.9% of patients taking Mimrylo needed no phlebotomies during the 32-week period, compared with 32.9% of patients on placebo. The study measured the share of patients who did not meet criteria for phlebotomy between weeks 20 and 32.

FDA statement

The most common adverse reactions were injection site reactions and anemia, the agency said.

Tanya Wroblewski, M.D., director of the FDA’s Division of Nonmalignant Hematology, said the approval offers a new, first-in-class option with the potential to reduce patient burden.

The approval was granted to Takeda Pharmaceuticals America, Inc. The FDA also said Mimrylo received priority review.

Next steps

The approval gives adults with polycythemia vera a new treatment option that may reduce the need for repeated phlebotomy. The FDA announcement did not provide additional commercial launch details.

Sources

• FDA press announcement: FDA approves first drug of its kind for polycythemia vera, a rare blood disorder

Editorial note: This article was prepared with AI assistance and includes source attribution for reader review.