Myelofibrosis Is a Rare Cancer That Impacts the Blood and Bone Marrow

A diagnosis of myelofibrosis can feel overwhelming. Understanding the basics may help you feel more in control.

What Is Myelofibrosis?

 

  • Myelofibrosis (my-ah-lo-fye-BRO-sis; MF) is a type of blood cancer in a group called myeloproliferative neoplasms (MPNs), which affect the blood and bone marrow—the spongy tissues inside the bones
  • If it develops on its own, it’s called primary myelofibrosis. If it develops from another MPN, such as polycythemia vera (PV) or essential thrombocythemia (ET), it’s called secondary myelofibrosis

How could myelofibrosis affect your body?

Though myelofibrosis affects different people in different ways, it typically involves:

  • Bone marrow scarring - Ongoing inflammation causes scar tissue to slowly build up in your bone marrow, replacing the space where healthy blood cells are made. This is called fibrosis
  • Less blood cell production - As the scar tissue builds, your bone marrow can’t keep up, making it harder for your body to produce the red blood cells, white blood cells, and platelets it needs to function properly
  • Enlarged spleen - As your bone marrow cannot make enough healthy blood cells, the spleen may begin to produce blood cells and increase in size. This is called splenomegaly, and it may make you feel full too quickly or have pain under your left rib
About 25,000 people in the United States have myelofibrosis

While myelofibrosis is a rare cancer, you’re not alone

Myelofibrosis can affect anyone, regardless of gender or race.

 

Each person experiences myelofibrosis in their own way. For instance, many people with myelofibrosis have anemia.

Anemia Prevalence Rises Over Time in People With Myelofibrosis

Eventually, virtually everyone with myelofibrosis develops anemia.

Each Person’s Myelofibrosis Symptoms Tell a Different Story

 

Some symptoms may appear, fade, or change over time, and what you feel may be very different from anyone else’s journey.

Some common symptoms are:

Anemia

What is it? When you have a low red blood cell count.

How might it show up? Your body may feel weak.

How might you know if it’s getting worse? You could be fatigued or having trouble catching your breath.

 

Low Platelet Count

What is it? When your body can’t make enough platelets (a type of blood cell), your blood can’t clot properly.

How might it show up? You may find that you bleed and/or bruise more easily.

How might you know if it’s getting worse?

If you get nosebleeds, bleeding gums, and/or new spots or patches on your skin.

Other Myelofibrosis Symptoms

Other symptoms may include:

  • Bone pain
  • Night sweats
  • Weight loss
  • Itching
  • Fever
  • Abdominal pain or pain under the left rib

Patient Videos

Understanding Symptoms—Experiences Based on Real Patient Stories

Discover more about living with symptoms.

It was a couple of years after my diagnosis that my spleen started to swell. I found an oncologist that has been wonderful, calm, and reassuring. They keep me in the loop so I can be an active participant in my care.

–Real patient, compensated by GSK.

Getting Diagnosed—Experiences Based on Real Patient Stories

See what a diagnosis journey may look like.

If You Are Experiencing Symptoms of Myelofibrosis, Don’t Wait to Speak to Your Doctor About Appropriate Treatment Options.

Myelofibrosis Symptom Tracker PDF image

Track Your Myelofibrosis Symptoms

Use this helpful monthly calendar to keep track of your myelofibrosis symptoms.

Caring for a Loved One Who Has Myelofibrosis With Anemia?

Find resources for caregivers and their loved ones.

How OJJAARA Works

Learn how OJJAARA works to treat myelofibrosis with anemia.

Approved Use & Safety Info

Approved Use

Important Safety Information

Approved Use

OJJAARA is a prescription medicine used to treat adults with certain types of myelofibrosis (MF) who have anemia. It is not known if OJJAARA is safe and effective in children.

Important Safety Information

OJJAARA may cause serious side effects, including:

  • Risk of Infections. People who take OJJAARA may develop serious infections that can lead to death, such as bacterial and viral infections, including COVID-19. If you have an active infection, your healthcare provider should not start treatment with OJJAARA until your infection is gone. If you have had hepatitis B for a long time (chronic), OJJAARA may cause your hepatitis B to become active again, and your healthcare provider will check your blood for active hepatitis B before starting treatment. Your healthcare provider will monitor you and treat you for any infections that you get during treatment with OJJAARA. Tell your healthcare provider right away if you develop any of the following symptoms of infection:
    • fever
    • chills
    • cough
    • breathing problems
    • diarrhea
    • vomiting
    • pain or burning feeling when passing urine
  • Low platelet and white blood cell counts. OJJAARA may cause new or worsening low platelet and white blood cell counts. Low platelet counts may increase your risk for bleeding and low white blood cell counts may increase your risk for infection. Your healthcare provider will do blood tests to check your blood counts before you start taking OJJAARA and during treatment. Tell your healthcare provider right away if you have any signs of bleeding during treatment with OJJAARA, including:
    • unusual bleeding
    • black or tarry stools
    • bruising
  • Liver problems. OJJAARA may cause new or worsening increased liver enzymes and bilirubin in your blood. Your healthcare provider will check your liver enzymes before starting treatment, every month for the first 6 months of treatment, and then as needed during treatment with OJJAARA. Your healthcare provider may stop treatment with OJJAARA if your liver enzymes increase. Tell your healthcare provider if you develop any of the following signs or symptoms of liver problems:
    • tiredness
    • loss of appetite
    • pain in your right upper stomach area (abdomen)
    • dark urine
    • yellowing of your skin or the white part of your eyes
  • Severe skin reactions. Severe skin reactions that can be life-threatening have occurred with OJJAARA. Tell your healthcare provider or get medical help right away if you get any of the following signs or symptoms of severe skin reactions, with or without fever:
    • rash that keeps getting worse
    • severe rash
    • reddened skin
    • flu-like symptoms
    • skin pain or burning
    • blistering of the lips, eyes, or mouth
    • blisters on the skin
    • skin peeling
  • Major cardiovascular events such as heart attack, stroke, and death. Major cardiac events have happened, especially in people with cardiac risk factors and who are current or past smokers, taking another Janus kinase (JAK) inhibitor to treat rheumatoid arthritis. OJJAARA is in the JAK family of medicines. Get emergency help right away if you have any symptoms of a heart attack or stroke while taking OJJAARA, including:
    • discomfort in your chest that lasts for more than a few minutes, or that goes away and comes back
    • severe tightness, pain, pressure, or heaviness in your chest, throat, neck, or jaw
    • pain or discomfort in your arms, back, neck, jaw, or stomach
    • shortness of breath with or without chest discomfort
    • breaking out in a cold sweat
    • nausea or vomiting
    • feeling lightheaded
    • weakness in one part or on one side of your body
    • slurred speech
  • Blood clots. Blood clots in the veins of the legs (deep vein thrombosis, DVT) or lungs (pulmonary embolism, PE) have happened in some people taking another JAK inhibitor to treat rheumatoid arthritis, and may be life-threatening. Tell your healthcare provider if you have had blood clots in the veins of your legs or lungs in the past. Tell your healthcare provider right away if you have any signs and symptoms of blood clots during treatment with OJJAARA, including:
    • swelling, pain, or tenderness in one or both legs
    • sudden, unexplained chest pain
    • shortness of breath or difficulty breathing
  • New cancers. New cancers, including lymphoma and other cancers, except non-melanoma skin cancer, have happened in some people taking another JAK inhibitor to treat rheumatoid arthritis. The risk of new cancers is further increased in people who smoke or who smoked in the past.
  • Worsening of symptoms after interruption or stopping treatment. Signs and symptoms of myelofibrosis may worsen after you stop treatment with OJJAARA. Do not interrupt or stop treatment with OJJAARA without talking to your healthcare provider. If you need to stop treatment with OJJAARA, your healthcare provider may give you instructions for slowly stopping treatment. Tell your healthcare provider right away if you get any of the following signs and symptoms after stopping treatment with OJJAARA:
    • fever
    • trouble breathing
    • feeling dizzy or lightheaded
    • weakness
    • night sweats
    • pain in the left upper stomach (abdomen) area or left shoulder

 

The most common side effects of OJJAARA include:

  • low platelet count
  • bleeding
  • bacterial infection
  • tiredness
  • dizziness
  • diarrhea
  • nausea

These are not all the possible side effects of OJJAARA. Call your doctor for medical advice about side effects.

 

Before taking OJJAARA, tell your healthcare provider about all your medical conditions, including if you:

  • have an infection
  • have or have had hepatitis B
  • have or have had liver problems
  • have had a heart attack, or have or have had other heart problems, or stroke
  • have or have had a blood clot
  • smoke or were a smoker in the past
  • have or have had any other cancers
  • are pregnant or plan to become pregnant. OJJAARA may harm your unborn baby.
    Females who are able to become pregnant:
    • You should use effective birth control (contraception) during treatment and for 1 week after the last dose of OJJAARA.
    • Tell your healthcare provider right away if you think you are pregnant or become pregnant during treatment with OJJAARA.
  • are breastfeeding or plan to breastfeed. It is not known if OJJAARA passes into your breast milk. You should not breastfeed during treatment and for 1 week after the last dose of OJJAARA. Talk to your healthcare provider about the best way to feed your baby during this time.

 

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Taking OJJAARA with certain other medicines may affect the amount of OJJAARA or the other medicines in your blood and may increase your risk of side effects.

 

Please see full Prescribing Information, including Patient Information for OJJAARA.

You are encouraged to report negative side effects of prescription drugs to the FDA.
Visit www.fda.gov/medwatch or call 1-800-FDA-1088. You may also report negative side effects to GSK at gsk.public.reportum.com or 1-888-825-5249.
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Explore the GSK Help Center website to find customer service support and contact information.

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If you don’t have prescription coverage or need help paying for your medicines, call us at 1-844-4GSK-ONC (1-844-447-5662).