Understand and treat polycythemia vera

Polycythemia vera is a condition in which the bone marrow makes too many red blood cells, white blood cells, and platelets , which can increase the risk of blood clots.

Too many red blood cells are the most prominent clinical sign of polycythemia vera. A mutation in the JAK2 gene, a protein involved in cell signaling, has been found in many people with this disease.

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Who gets polycythemia vera?

Polycythemia vera can occur at any age, but it often occurs later in life. If you look at the ages of all people with this condition, the average age at diagnosis is 60, and this is not often seen in people under 40. The incidence of polycythemia vera is slightly higher in men than in women. and the highest among men between 70 and 79 years old.

How many people were affected?

It's hard to say for sure, as a person can have this condition for a long time and not know it, but it is estimated that between one and two people out of 100,000.

According to Incyte Corporation, a Wilmington, Delaware-based biopharmaceutical company that specializes in oncology, about 25,000 people in the United States live with polycythemia vera and are considered uncontrolled because they develop resistance or intolerance to the main drug, hydroxyurea. …

Is it cancer or disease?

Polycythemia vera has some characteristics that are similar to cancer in that it involves the uncontrolled division of an immature cell and is incurable. It is understandable that knowing this, knowing that you or your loved one has this disorder can be stressful. However, keep in mind that this disease can be effectively treated for a long time.

The National Cancer Institute defines polycythemia vera as follows: 'A disease in which there are too many red blood cells in the bone marrow and blood, causing the blood to thicken. It can also increase the number of white blood cells and platelets. Extra blood cells can collect in the spleen and cause it to enlarge. They can also cause bleeding problems and blood clots in the blood vessels. "

According to the Leukemia and Lymphoma Society, people with polycythemia vera have a slightly higher risk of developing leukemia from the disease and / or certain prescription drugs than the general population. Although it is a chronic condition that does not respond to treatment, remember that it can usually be treated effectively over time and does not generally reduce life expectancy. Also, complications can be treated and prevented under medical supervision.


Yes, but the details of the risk of progression are still being explored. Although people can remain asymptomatic for many years, polycythemia vera can lead to the development of various symptoms and signs, including fatigue, itching, night sweats, bone pain, fever, and weight loss. About 30% to 40% of people with polycythemia vera have an enlarged spleen. In some people, this can lead to debilitating symptoms and cardiovascular complications. The burden of this disease is still being actively investigated.


A test called hematocrit concentration is used both to diagnose polycythemia vera and to measure a person's response to therapy. Hematocrit is the ratio of red blood cells in blood volume and is generally expressed as a percentage or increase in the concentration of hemoglobin in the blood.

In healthy people, the hematocrit concentration ranges from 36 to 46% in women and 42 to 52% in men. Other information that can be obtained from blood tests is also useful in diagnosis, including the presence of a mutation, the JAK2 mutation, in blood cells. Although it is not necessary for a diagnosis, some people may also have a bone marrow test as part of an exam and exam.

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According to the Leukemia and Lymphoma Society, phlebotomy or drawing blood from a vein is the usual starting point of treatment for most patients. This can lower the hematocrit concentration, which generally results in a reduction in some symptoms such as headaches, ringing in the ears, and dizziness.

Drug therapy may include agents that can reduce the concentration of red blood cells or platelets, compounds called myelosuppressive agents. The most commonly used myelosuppressive agent for polycythemia vera is hydroxyurea, which is taken by mouth. The most common side effects include cough or hoarseness, fever or chills, back or side pain, and pain or difficulty urinating.

About Jakafi for polycythemia vera

Jakafi (ruxolitinib) is a prescription drug used to treat people with polycythemia vera who have already taken hydroxyurea, but it has not worked or cannot tolerate it. Jakafi is also used to treat certain types of myelofibrosis – scarring of the bone marrow.

According to the FDA, Jakafi works by inhibiting enzymes called Janus Associated Kinase (JAK) 1 and 2, which are involved in regulating blood and immune function. Approval of polycythemia vera will help reduce the likelihood of an enlarged spleen (splenomegaly) and reduce the need for a phlebotomy, a procedure to remove excess blood from the body.

The most common side effects associated with the use of Jakafi in participants with polycythemia vera in qualified clinical trials were low red blood cell counts ( anemia ) and low platelet counts (thrombocytopenia). The most common non-blood side effects were dizziness, constipation, and shingles.

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