JAK Inhibitors for Myelofibrosis
- JAK inhibitors are transforming myelofibrosis treatment, offering longer life and fewer side effects.
- These drugs target specific pathways, reducing symptoms like anemia and spleen enlargement.
- Your doctor will run tests to come up with a score to see if a JAK inhibitor is right for you. They usually work best for intermediate to high-risk patients.
- There are four JAK inhibitors used to treat myelofibrosis: Ruxolitinib, Fedratinib, Pacritinib, and Momelotinib. Each carries unique benefits and side effects.
“The research in this disease has provided much needed hope and we are striving to make this disease more treatable, more curable and [make] the quality of life of patients living with myelofibrosis better and better each day,” Dr. Swati Goel, an associate professor at Montefiore Einstein Comprehensive Cancer Center in Bronx, New York, tells SurvivorNet.
What is myelofibrosis?
Read More- Enlarged spleen size
- Cell counts drop
- Weight loss
- Fatigue
There were very few options to treat myelofibrosis until recently. But Dr. Goel says that’s changing with the introduction of a new type of medication.
Related: Understanding Primary Myelofibrosis
What are JAK inhibitors?
Janus kinase (JAK) inhibitors improve the symptoms of myelofibrosis, making the disease more manageable for many patients. They have improved survival significantly as well.
JAKs are enzymes involved in the growth and function of blood cells and the immune system. A JAK inhibitor is a type of medicine that blocks certain signals inside the body’s cells that can cause problems like swelling, pain, and other symptoms.
As Dr. Goel explains it, JAK inhibitors help reduce these symptoms and control the disease by blocking these signals.
“JAK inhibitors, as the name suggests, inhibit the JAK pathway,” she says. “By inhibiting this pathway, JAK inhibitors primarily aid in controlling the disease. They help alleviate symptoms related to splenomegaly, bone pains, fatigue, itching, and reduce the overall disease burden.”
Dr. Goel highlights 4 specific JAK inhibitors that have shown promise in treating myelofibrosis.
- Ruxolitinib (Jakafi) can shrink an enlarged spleen and ease symptoms like fatigue, itching, and night sweats. Studies show that it can extend the survival of a myelofibrosis patient and improve quality of life more so than placebo. Ruxolitinib stands out as the first FDA-approved drug to offer such benefits. However, it can cause problems.Taking ruxolitinib may reduce blood cell counts. It may increase the risk for bleeding, anemia, and infection. Anyone who takes this drug will need regular checkups to test their blood levels.
- Fedratinib (Inrebic) can help reduce the size of an enlarged spleen and improve symptoms like fatigue, itching, and night sweats. It can also improve survival and quality of life. It’s the second drug that has shown such benefits in clinical trials and may be right for patients who don’t respond well to Ruxolitinib. However, Fedratinib can also increase the risk of bleeding, anemia, and infections. Therefore, it’s necessary for people on this drug to have regular blood tests.
- Pacritinib (Vonjo) is approved for patients with low platelets. It may effectively reduce spleen size and other symptoms. It can lower the risk of bleeding. However, Pacritinib can also cause heart problems, such as irregular heartbeat, chest pain, and shortness of breath. Therefore, people who take pacritinib need to have regular heart tests.
- Like the other three drugs in this category, Momelotinib (Ojjaara) can help reduce the size of an enlarged spleen and improve symptoms such as fatigue, itching, and night sweats. It is different from the other drugs because it can also stop a protein that controls iron levels, which may help patients with low red blood cells. This may be especially helpful for patients with anemia. Specific side effects include nausea, diarrhea, and peripheral neuropathy, a nerve disorder that can cause pain, numbness, and tingling in the hands and feet. Anyone taking Momelotinib should have regular blood tests.
Related: Managing Anemia in Myelofibrosis in New Treatment Options
“As the treatment options are getting better, the survival is getting better, patients are living longer and more importantly, more meaningful and happier life,” Dr. Goel says of the JAK inhibitors. “They’re more comfortable, they are pain-free, and they’re living their life as they want to be.”
Are you a good candidate for a JAK inhibitor?
To see if you will benefit from taking a JAK inhibitor, your doctor will run some tests and come up with a score. Patients experiencing symptoms like anemia, spleen enlargement, and discomfort from myelofibrosis may find relief with JAK inhibitors.
Scoring systems for myelofibrosis evaluate various factors to predict disease progression and help guide treatment decisions including:
- Blood counts
- Age
- General health.
Your score can tell how aggressive your disease is, how urgently you need treatment, and if you are likely to benefit from JAK inhibitor therapy.
Typically, those with intermediate to high-risk disease and those who have symptoms like anemia, spleen enlargement, and discomfort will benefit the most from taking a JAK inhibitor.
Cost of JAK inhibitors
In the United States, the cost and availability of JAK inhibitors for treating myelofibrosis vary widely based on insurance coverage, manufacturer assistance programs, and pharmacy pricing.
Most private insurance plans and Medicare do cover these treatments, but just how much depends on the carrier.
To support patients facing financial challenges, some pharmaceutical companies offer patient assistance programs to provide discounts or even free medication for some patients. Check with your doctor and your insurance provider to make sure you understand the cost and coverage for these drugs.
Related: SurvivorNet’s Clinical Trial Finder
Questions for Your Doctor
For anyone considering JAK inhibitors for myelofibrosis treatment, here are some essential questions to discuss with your healthcare provider:
- What tests will you run to see if I am a good candidate for a JAK inhibitor?
- Which drugs are you considering for my treatment?
- How will JAK inhibitors improve my symptoms and quality of life?
- What side effects should I expect, and how can we manage them? A
- re there any long-term risks associated with JAK inhibitor therapy?
- How will we monitor the effectiveness of the treatment over time?
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