FDA Approves Treatment for Rare Blood Disease

Besremi is the first interferon approved to treat a disease that causes the overproduction of red blood cells.

The FDA has approved Besremi (ropeginterferon alfa-2b-njft) injection to treat adults with polycythemia vera, a blood disease that causes the overproduction of red blood cells. The excess cells thicken the blood, slowing blood flow and increasing the chance of blood clots.

Besremi, which was developed by PharmaEssential, is the first FDA-approved medication for polycythemia vera that patients can take regardless of their treatment history, and the first interferon therapy specifically approved for polycythemia vera.

Besremi is a long-acting drug that patients take by injection under the skin once every two weeks.

The approval of Besremi was based on a multicenter, single-arm trial that lasted seven and half years. In this trial, 51 adults with polycythemia vera received Besremi for an average of about five years. Besremi’s effectiveness was assessed by looking at how many patients achieved complete hematological response, which meant that patients had a red blood cell volume of less than 45% without a recent phlebotomy, normal white cell counts and platelet counts, a normal spleen size, and no blood clots. Overall, 61% of patients had a complete hematological response.

Polycythemia vera affects approximately 6,200 Americans each year.