Jakafi is a medicine licensed for the treatment of a certain type bone marrow disorder called myelofibrosis. It is designed to help reduce the size of an enlarged spleen and relieve symptoms of myelofibrosis, such as night sweats and bone pain. This medicine comes as a tablet that is taken twice daily. Potential side effects include dizziness, headaches, and bruising.
What Is Jakafi?Jakafi™ (ruxolitinib) is a prescription medication approved to treat a disorder of the bone marrow known as myelofibrosis. Myelofibrosis is characterized by scarring of the bone marrow. Jakafi is used to treat people who are considered intermediate-risk or high-risk, based on their expected survival. It belongs to a class of medicines known as kinase inhibitors.
How Does Jakafi Work?
Jakafi works by blocking two enzymes in the body known as janus-associated kinase 1 (JAK1) and 2 (JAK2). These two enzymes help control the formation of blood cells. Myelofibrosis is associated with abnormal activity of JAK1 and JAK2, which causes blood cells to be made in organs such as the spleen. This, in turn, leads to enlargement of the spleen.
By inhibiting the action of the abnormal JAK1 and JAK2 enzymes, Jakafi can help reduce spleen size and subsequent symptoms of myelofibrosis.
Clinical EffectsClinical studies have been done to determine the effectiveness of Jakafi in people with myelofibrosis who had enlarged spleens and needed treatment because of symptoms. In these studies, Jakafi was shown to reduce spleen size and relieve myelofibrosis symptoms, including:
- Abdominal (stomach) discomfort
- Night sweats
- Bone or muscle pain.
In these studies, more people given Jakafi had a 35 percent reduction in the size of their spleen compared to people given a placebo (a "sugar pill" with no active ingredients) or other best available treatments. In addition, more people given Jakafi had at least a 50 percent reduction in their symptoms, compared to people given the placebo.