Tag Archive for: Inrebic

How Does Inhibitor Therapy Work to Treat Myelofibrosis?

How Does Inhibitor Therapy Work to Treat Myelofibrosis? from Patient Empowerment Network on Vimeo.

What is inhibitor therapy? Dr. Joseph Scandura reviews approved JAK inhibitor therapies and explains how they work to treat myelofibrosis.

Dr. Joseph Scandura is Associate Professor of Medicine and Scientific Director of the Silver MPN Center at Weill Cornell Medicine. Learn more about Dr. Scandura, here.

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Which Gene Mutations Impact Myelofibrosis Treatment Options?

What Are the Considerations When Choosing Myelofibrosis Therapy?

What’s YOUR Role in Making Myelofibrosis Treatment Decisions?


Transcript

Katherine Banwell:

How does inhibitor therapy work to treat myelofibrosis? 

Dr. Scandura:

So, the therapies that we have now that are approved therapies that are in this class are  ruxolitinib (Jakafi) and fedratinib (Inrebic) 

Both of these agents act to block signaling through a protein called JAK2. You can think of JAK2 as being part of the antennae system that a cell uses to communicate with the rest of the body. And so, our blood-forming cells have a lot of input from the body saying, “Okay, we need some of these kinds of cells, we need some of those kinds of cells,” and it’s a very adaptive system. And JAK2 is involved in a lot of the signaling in this as part of the antennae system.  

And what happens in the myeloproliferative neoplasms is that signaling is a bit excessive. 

And so, it’s like the volume is turned up too loud and the signaling is causing the cells to do things, make too many cells, make the wrong kinds of cells, and JAK2 is part of that signaling system. So, these inhibitors kind of help turn down the volume of the signaling in these blood-forming cells. They are drugs that have good activity in improving symptoms, they have great success in reducing the size of the spleen, they can be useful for a few years to many years. They are not curative therapies. We don’t think of them as therapies that change the course of disease, but they certainly have an important role in helping people feel better. There are other inhibitor therapies that are in clinical development. 

So, clinical trials of some of these drugs have really impressive activity, but none is approved yet by the FDA.  

I hope and expect we’ll have a couple more drugs available in the coming years. And there’s a lot of excitement in clinical trials in terms of some of the activities that are being seen, and really quite tolerable therapies, so not a lot of side effects for patients. And so, I think it’s kind of an exciting time for physicians and for patients and a lot more options now and, I think, a lot more options coming down the line.

Have You Had These Essential Myelofibrosis Tests?

Have You Had These Essential Myelofibrosis Tests? from Patient Empowerment Network on Vimeo.

What are the essential tests that should follow a myelofibrosis diagnosis? Dr. Joseph Scandura reviews the necessary laboratory testing, along with a discussion of next generation sequencing, and explains how often bone marrow biopsies should take place.

Dr. Joseph Scandura is Associate Professor of Medicine and Scientific Director of the Silver MPN Center at Weill Cornell Medicine. Learn more about Dr. Scandura, here.

Related Programs

Which Gene Mutations Impact Myelofibrosis Treatment Options?

What Are the Considerations When Choosing Myelofibrosis Therapy?

How Does Inhibitor Therapy Work to Treat Myelofibrosis?


Transcript

Katherine Banwell: 

What testing should take place following a myelofibrosis diagnosis? 

Dr. Scandura:  

So, a diagnosis of myelofibrosis always comes after a bone marrow exam and a physical examination. Often, patients have an enlarged spleen and blood count testing and a variety of other laboratory tests. So, after that and a diagnosis is made of myelofibrosis and, sort of, coincident with the diagnosis, we often look for molecular markers of myelofibrosis. So, these are malignancies of the bone marrow, cancers, if you will, on the bone marrow, although the term is scarier than or is different than what we think of for many malignancies in how it acts. But the myelofibrosis, this is a disease that’s characterized by, really, mutations in the malignant cells, the abnormal cells. 

They’re really just one of three genes. And so, JAK2 being one of the genes, calreticulin or CALR being another one, and MPL one.  

And more than 90 percent are people having mutation in just one of those three genes. And so, often at the time of diagnosis, tests for those mutations are done, and they help eliminate the possibilities of other causes of myelofibrosis – infections, rheumatological diseases. Sometimes, you can have marrow fibrosis but they don’t go along with mutations and the same clinical situation. And so, at the time of diagnosis, we usually know something about a mutation in JAK2, CALR, or MPL.    

More commonly now, and it’s increasingly common over the past 10 years in, I would say, in New York City and many places across the country, we also look more broadly for other common mutations in the MPN cells. And these are what we refer in the batch as next generation sequencing or NGS panels, and we use the term panels because we’re looking at from a few tens to even 100 or a couple hundred genes for mutations that occur far less frequently than in JAK2 or MPL or CALR.  

But they occur often enough that some of them we use to help guide treatment decision-making or approach to therapy. The reality of it is that that the technology to sequence and identify mutations has really outstripped our knowledge of what to do with all of that information. 

And, for the vast majority of people, it comes down to do you have a marker, a genetic marker that tends to go along with higher risk, meaning a higher likelihood of something that we don’t want to have happen. And in that instance, although it may be looking at a hundred or so genes, it comes down to a binary thing – either you have or you don’t have. 

Katherine Banwell:

Is there any other testing that you usually want to do? 

Dr. Scandura:

Laboratory testing, for sure and, as I mentioned before, a bone marrow exam. But physical examination, some people might do imaging of the spleen size. Honestly, I don’t routinely do that outside of the setting of the clinical trial. I don’t really think it dictates therapy very often. 

And if the spleen is so small that you can’t feel it on physical exam, it probably isn’t clinically meaningful anyway in terms of something to treat. It might be there, but it doesn’t really change things too much.   

Katherine Banwell:

How often should patients have a bone marrow biopsy? 

Dr. Scandura:

So, I’ll answer there is no standard in terms of monitoring for myelofibrosis with the marrow or otherwise. My personal approach is I do a marrow when I think it’s going to help medical decision-making. And so, for a patient who’s got early myelofibrosis, who’s been very stable, responding well to therapy, that could be three, five years between marrow exams. 

For somebody who’s being considered for a clinical trial, oftentimes, a marrow exam is required before they start on the clinical trial and at various intervals afterwards. If there’s somebody who had been stable and something is changing, like the blood counts are changing or his symptoms are changing, or any of a number of clinical features, then I might look in the marrow to see what’s happening there, to see if explains and can help guide a treatment approach to help people feel better. So, there is no single standard, but my personal approach is to do a bone marrow exam when I think it’s going to help make a decision.  

What Are the Treatment Options for Myelofibrosis?

What Are the Treatment Options for Myelofibrosis? from Patient Empowerment Network on Vimeo.

When choosing a treatment for myelofibrosis (MF), where do you start? Dr. Laura Michaelis reviews the available options for MF therapy, including a discussion of stem cell transplant. 

Dr. Laura Michaelis is hematologist specializing in myeloproliferative neoplasms (MPNs) at Froedtert & the Medical College of Wisconsin, where she also serves as Associate Professor of Medicine. Learn more about Dr. Michaelis here.


Related Resources

 

Which MPN Treatment is Right for You: Factors to Consider

 

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MPN Treatment Decisions: Which Path is Best for You?


Transcript:

Dr. Michaelis:                       

So, myelofibrosis is among the most aggressive of the myeloproliferative neoplasms. And yet, it still has a broad swath of risk associated with it. And that means that compared to essential thrombocythemia and polycythemia vera, myelofibrosis – primary myelofibrosis tends to be more aggressive and needs to be treated more aggressively.

There are a group of patients who have what we call low-risk or even intermediate 1 risk myelofibrosis who don’t need treatment – who can be followed, whose blood counts can be checked, who can be regularly seen by their doctor, and who can avoid treatment for some period of time, depending on their risk factors.

And so, if you’re diagnosed with primary myelofibrosis, the first question is do I need treatment? And the second question – if the answer to that is yes, then you have to figure out why you need treatment. There is currently only one intervention that is known to be curative in myelofibrosis, and that’s the use of stem cell transplant.

Stem cell transplant, which is also called bone marrow transplant or allogeneic hematopoietic stem cell transplant, is basically a procedure where a donor is able to have their stem cells collected. And then the recipient, who’s the person with the myelofibrosis, undergoes a series of chemotherapy treatments to basically wipe out the bone marrow that they have. And it’s then replaced, using basically a blood transfusion of the stem cells of someone else, which then grow up into the recipient.

This has been shown to be safe in myelofibrosis – well, relatively safe – if done in the right person, who’s relatively fit, and done at the right stage of disease. It’s not a procedure that everybody can tolerate. People need to be pretty fit. And it should be performed at a place that has done numerous transplants for myelofibrosis since it’s a relatively complicated form of stem cell transplant. That being said, in the right person at the right time, it’s an excellent opportunity and option for these patients.

Now in patients who can’t tolerate transplant or where that’s not the right step to go, we have medications. And those medications can sometimes delay the worsening of symptoms. They can certainly control spleen size, improve people’s quality of life, and often improve survival. And the medications that we’re talking about here are called JAK-STAT inhibitors.

And the first approved, and the one that’s most commonly used, is a medicine called ruxolitinib.

This is an oral pill – a pill that you take twice a day and has excellent data that supports that it shrinks the spleen in people with myelofibrosis, that it improves symptoms. And in people with advanced polycythemia vera, decreases the blood count without leading to iron deficiency and also improves symptoms and spleen size.

There’s another JAK-STAT inhibitor that’s approved. That’s a medicine called fedratinib. And it was recently approved in people who had progressed off of myelofibrosis or even in people – or after ruxolitinib or in people who – instead of taking ruxolitinib.

Now in essential thrombocythemia, polycythemia vera, and other times even myelofibrosis, we have other treatments that are commonly used that can be exceedingly helpful in controlling symptoms and blood counts. Those include, for example, hydroxyurea, pegylated interferon, and sometimes treatments aimed at helping anemia, like steroids or derivatives of thalidomide.

And finally, I don’t want to let this end without saying that clinical trials are often an excellent possibility for patients with these conditions, like myelofibrosis.

So, when you are contemplating starting a treatment, it’s really important to ask your physician whether or not there’s any clinical trials that are right for you.