How it is administered

Fedratinib is taken by mouth as a capsule, typically once daily. Each capsule contains 100 mg of fedratinib. The usual recommended dose is 400 mg once daily, with or without food. For patients who have trouble swallowing capsules, the contents can be mixed with a nutritional supplement (like Ensure® Plus) and taken orally or through a nasogastric tube within 2 hours of preparation.

How it works

Fedratinib is a type of medication called a kinase inhibitor. It works by blocking the activity of specific proteins in the body known as Janus Associated Kinase 2 (JAK2) and FMS-like tyrosine kinase 3 (FLT3). These proteins are involved in the signaling pathways that control the production and growth of blood cells.

In myelofibrosis, abnormal activation of JAK2 leads to the overproduction of abnormal blood cells and scarring (fibrosis) in the bone marrow. By inhibiting JAK2, fedratinib helps to reduce the abnormal cell growth, decrease spleen size, and improve symptoms such as fatigue, night sweats, and bone pain. Fedratinib also reduces the activity of certain signaling proteins (STAT3/5), which further helps control the disease.

Who Should take it

Fedratinib is indicated for adults with intermediate-2 or high-risk primary or secondary myelofibrosis (including myelofibrosis that develops after polycythemia vera or essential thrombocythemia). It is used in patients who have symptoms related to myelofibrosis, such as an enlarged spleen or significant discomfort from the disease.

Your doctor may recommend fedratinib if you have not responded well to other treatments or if your symptoms are significantly affecting your quality of life. It is important to have your blood counts and thiamine (vitamin B1) levels checked before starting this medication.

Who should not take it

Fedratinib should not be started in patients who have a thiamine (vitamin B1) deficiency until this has been corrected. It is not recommended for use in children, as its safety and effectiveness have not been established in pediatric patients.

Women who are pregnant or breastfeeding should not use fedratinib, as there is not enough information about its safety in these situations. Patients with severe liver problems should use caution, and those with severe kidney impairment may require a lower dose. Always discuss your full medical history with your doctor before starting fedratinib.

Commonly used with

Fedratinib is often used alone for the treatment of myelofibrosis. However, all patients taking fedratinib should also receive daily thiamine (vitamin B1) supplementation to reduce the risk of Wernicke's encephalopathy. Other supportive treatments, such as antiemetics for nausea or antidiarrheal medications, may be recommended to help manage side effects.

Commonly tested with

Fedratinib has been compared to placebo and best available therapy in clinical trials for myelofibrosis. It is sometimes tested in patients who have previously been treated with other JAK inhibitors, such as ruxolitinib. Your doctor may monitor your response to fedratinib with regular blood tests and imaging studies to track spleen size and symptom improvement.