Ropeginterferon alfa-2b (trade name: Besremi) has been approved in Germany since February 2019 for the treatment of polycythemia vera (PV) in adults. It is an option for patients whose spleen has not yet become so enlarged that it causes problems.

Polycythemia vera is a rare chronic disease where too many red blood cells are made in the bone marrow. Most patients also have too many white blood cells and platelets in their blood due to a genetic change. This high number of blood cells hinders the flow of blood, which may lead to a blood clot in a vein (thrombosis) or a blocked blood vessel (embolism). The risk of developing acute leukemia is also higher. The typical signs of PV include redness in the face and on the arms and legs, and severe itching.

As the disease progresses, the production of new blood cells moves from the bone marrow to the spleen. This makes the spleen grow larger (splenomegaly), which may cause symptoms like a feeling of pressure or pain.

Ropeginterferon alfa-2b is similar to a human hormone. The aim of treatment with this drug is to stop the blood cells from multiplying so fast.


Ropeginterferon alfa-2b is injected under the skin (subcutaneously) using a pre-filled pen. One pre-filled pen contains either 250 micrograms or 500 micrograms of ropeginterferon alfa-2b.

The treatment starts with a 100-microgram injection of the medication. The injections are then increased by 50 micrograms every two weeks until the levels of blood cells have stabilized. The recommended maximum dose of ropeginterferon alfa-2b is 500 micrograms every two weeks.

Other treatments

Hydroxyurea is the standard treatment for PV in people who have not had any previous treatment.

Ruxolitinib is considered in people for whom hydroxyurea isn’t suitable.

Treatment of polycythemia vera also includes the regular drawing of blood from your veins (therapeutic phlebotomy).


In 2019, the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) wanted to look into the advantages and disadvantages of ropeginterferon alfa-2b when compared with the standard treatments for polycythemia vera in adults who don’t have a spleen enlargement that is causing symptoms.

But the manufacturer didn’t provide any suitable data with which to do the assessment.

More information

This information summarizes the main results of a review produced by the Institute for Quality and Efficiency in Health Care (IQWiG, Germany). The review was commissioned by the German Federal Joint Committee (G-BA) as part of the “early benefit assessment of medications.” On the basis of this review and the hearing received, the G-BA passed a resolution on the added benefit of ropeginterferon alfa-2b (trade name: Besremi).