FDA Approves Treatment for Rare Blood Disease Polycythemia Vera

Ropeginterferon alfa-2b-njft (Besremi) was approved by the US Food and Drug Administration (FDA) for injection to treat adults with polycythemia vera. Approval of Besremi was granted to PharmaEssentia Corporation on November 12.

This treatment is the first to be FDA approved for polycythemia vera that patients can use regardless of their treatment history. It’s also the first interferon therapy that’s specifically approved for polycythemia vera.

Polycythemia is a rare blood disease that causes the red blood cells to overproduce. The blood flow slows and the risk of blood clotting increases because the excess cells thicken the blood. Phlebotomies are often performed as treatment for polycythemia vera along with medicines, like ropeginterferon alfa-2b-njft, that reduce the number of blood cells in a patient.

“Over 7,000 rare diseases affect more than 30 million people in the United States. Polycythemia vera affects approximately 6,200 Americans each year,” Ann Farrell, MD, director, Division of Non-Malignant Hematology, FDA Center for Drug Evaluation and Research, said in a statement. “This action highlights the FDA’s commitment to helping make new treatments available to patients with rare disease.”

Treatment with ropeginterferon alfa-2b-njft was assessed for safety and effectiveness in a multicenter, single-arm trial that spanned 7.5 years. It included 51 adults with polycythemia vera who received ropeginterferon alfa-2b-njft treatment for an average of about 5 years.

The effectiveness of the treatment was determined by evaluating the patients’ achieved complete hematological response, or that patients had a red blood cell volume of less than 45% without a recent phlebotomy, normal white cell countries and platelet counts, a normal spleen size, and no blood clots.

The study results showed that 61% of patients had a complete hematological response. ropeginterferon alfa-2b-njft isn’t without risk. Some adverse events include liver enzyme elevations, low levels of white blood cells, low levels of platelets, joint pain, fatigue and more.

The method of ropeginterferon alfa-2b-njft is to attach to certain cell receptors in the body, initiating a chain reaction that makes the bone marrow reduce blood cell production. It’s a long-acting drug that’s administered through injection under the skin every 2 weeks.

If a reduction of excess blood cells is maintained for at least one year of treatment with ropeginterferon alfa-2b-njft, dosing can be reduced to once every 4 weeks.

Ropeginterferon alfa-2b-njft received orphan drug designation for this indication which provides incentives to support and motivate development of drug treatments for rare diseases.