Tag Archive for: Luspatercept

What Are the Currently Approved Myelofibrosis Therapies?

What Are the Currently Approved Myelofibrosis Therapies? from Patient Empowerment Network on Vimeo.

Expert Dr. Gabriela Hobbs shares an overview of available therapies and important considerations when choosing a myelofibrosis treatment plan.

Dr. Gabriela Hobbs is a hematology-oncology physician specializing in the care of patients with myeloproliferative neoplasms (MPN), chronic myeloid leukemia and leukemia. Dr. Hobbs serves as clinical director of the adult leukemia service at Massachusetts General Hospital. Learn more about Dr. Gaby Hobbs.

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Would you provide an overview of the currently approved therapies for myelofibrosis?  

Dr. Hobbs:

Sure, absolutely. So, I’ve alluded to this a little bit. So, in 2011, we had the first JAK inhibitor approved called ruxolitinib, the brand name is Jakafi. After that, we had the approval of Inrebic or fedratinib and then pacritinib or Vonjo, and then most recently momelotinib or Ojjaara. So, we have four different JAK inhibitors that are now approved for myelofibrosis.   

So, who needs to get a JAK inhibitor and how do we choose between the JAK inhibitors? So, the traditional indications for JAK inhibitors are, does a patient have bothersome symptoms from having a big spleen? Does a person have symptoms from their disease? Symptoms can include things like night sweats, itching, unintentional weight loss, brain fog, and fatigue. Fatigue can be challenging because of course many things can cause fatigue. But those are some of the symptoms that can occur with having this disease. So, if a patient has both splenomegaly symptoms or one or the other, they’re eligible for a JAK inhibitor.  

So, just having myelofibrosis doesn’t mean that you need to have a JAK inhibitor right away. Probably the most commonly used JAK inhibitor, and this will be the case probably for a long time, is ruxolitinib.  

The reason for that is that it’s been around for a long time, and it’s a very well-tolerated medication. Patients that have platelets that are very low, meaning platelets that are less than 50, should be considered for pacritinib first, as that’s the indication for that agent. Patients that don’t do that well on ruxolitinib initially, let’s say that the dose gets increased and the spleen and the symptoms are still present, but still have good blood counts, are good candidates for then receiving fedratinib. Fedratinib can also be given upfront. It rarely is given upfront, simply because ruxolitinib has been around for longer and it’s a better-tolerated medication.

So, therefore most providers feel more comfortable giving that upfront. I have had some patients that are concerned about the weight gain that is a side effect of ruxolitinib. For those patients, I’ve occasionally considered giving fedratinib first before ruxolitinib. And then lastly, we have momelotinib. It’s approved primarily for patients with myelofibrosis and anemia.  

Now momelotinib is still a JAK inhibitor, so it can still improve symptoms, and it still improves spleen size. So, I struggle with that recommendation of just using it for anemia in patients that don’t have splenomegaly or symptoms.   

But the FDA label was pretty broad, and it’s important to recognize that. So, how is momelotinib being used? It can be used in the upfront setting for patients that have spleen and symptoms, and also anemia, meaning low red blood cell levels. Or,  it can be used for patients that have been treated with a JAK inhibitor first and then develop anemia. So, momelotinib is given to continue to improve the spleen and symptoms, but also help the anemia.

So, that’s kind of like an overview of the four JAK inhibitors. Now we have a group of patients that maybe doesn’t have a lot of spleen symptoms or symptoms in general but has issues with having low hemoglobin. So, for those patients, we’ve used a variety of different medications, including medications that are called erythropoietin, which is a hormone that helps to boost the red blood cell levels.  

 A medicine that’s similar to testosterone that can also help boost the red blood cell levels called danazol (Danocrine). And then there’s a medication called luspatercept-aamt (Reblozyl) that has been approved for a related condition called myelodysplastic syndrome. And in some clinics, it can be used even though it’s not approved either by itself or in combination with ruxolitinib.

And then lastly, patients that have what is called high-risk myelofibrosis, meaning they have some mutations that may indicate that a patient has a higher risk of having complications of their disease, or they have very low blood counts, are usually considered high-risk. Those patients should be recommended and referred to transplantation as soon as they’re identified as having high-risk disease.  


When you say transplantation, you’re referring to stem cell transplant. 

Dr. Hobbs:

Yes, and I’m glad you said it that way actually. So, stem cell transplantation or bone marrow transplantation, same thing, interchangeable, same procedure. You got it.  


When considering therapy, how do you approach a treatment plan for someone diagnosed with myelofibrosis?  

Dr. Hobbs:

Great question. So, when approaching how I care for a patient with myelofibrosis, I take several things into account. The first thing is, who is this patient? What other medical conditions do they have? How impacted are they by their myelofibrosis? Then what I like to do is to plug in the numbers of the patient, their blood work, their mutations, etcetera, into one of the many risk calculators that we have to determine what the risk of their myelofibrosis is.   

If a patient is considered high-risk, I will generally consider transplantation or discuss a referral to a bone marrow transplantation in one of our first visits, if not the first visit. After that, I need to determine whether or not the patient has symptoms from their disease, and if so, if they should receive a JAK inhibitor. Then I’ll look through their blood work, what their symptoms are to decide which JAK inhibitor to use first.   

If really the spleen and symptoms aren’t the primary issue, if it’s more related to low blood counts, then we can think about treatments directed at improving the hemoglobin, for example. There may be a group of patients that don’t actually require any treatment when I first meet them. So, just providing them with education, what to expect. Then discussing more of the psychological impact of living with a condition and approaches to handle that, maybe more the focus of my care.

And in general, for most of my patients, we also talk about the rest of the care. So, not just what the blood work is and what medicine I’m going to start them on, but also other things that they can do to take care of themselves, including making sure that they are actively monitored by their primary care doctor or by other specialists if that’s still appropriate. You know, one of the things we don’t discuss that frequently in myelofibrosis, we discuss that more often in essential thrombocythemia or polycythemia vera is a risk of blood clots.  

But the truth is that myelofibrosis patients can also have risks of blood clots. So, therefore, making sure that patients with MF that may have issues like hypertension, diabetes, high cholesterol, etc., get those well-managed is also really important to prevent them from having blood clots. So, lifestyle management is also an important part of the care of a patient with myelofibrosis.  

Advances in Myelofibrosis Research

Advances in Myelofibrosis Research from Patient Empowerment Network on Vimeo.

What are the recent developments in the study and advancement of myelofibrosis treatment? MPN researcher Dr. Gabriela Hobbs discusses ongoing clinical trials for new JAK inhibitors, BET inhibitors, and anemia therapies, among others.

Dr. Gabriela Hobbs is a hematology-oncology physician specializing in the care of patients with myeloproliferative neoplasms (MPN), chronic myeloid leukemia, and leukemia. Dr. Hobbs serves as clinical director of the adult leukemia service at Massachusetts General Hospital. Learn more about Dr. Hobbs.

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What about myelofibrosis, Dr. Hobbs? What advances are being made in the care of patients with this more advanced MPN? 

Dr. Hobbs:

Yeah. So, in myelofibrosis, I would say it is almost difficult to keep track of how many clinical trials are currently open. So, in 2011, we had ruxolitinib approved, or Jakafi. That was the first JAK inhibitor. Since then, we’ve had two more JAK inhibitors approved, fedratinib (Inrebic) and most recently pacritinib (Vonjo). And we’re currently awaiting the fourth JAK inhibitor to be approved, and that’s called momelotinib.   

And in addition to the JAK inhibitors, there are lots of other clinical trials underway right now that are either alone – a drug by itself or a drug in combination with ruxolitinib.  

So, there are several Phase III studies. And the reason why that’s important is that after Phase III we usually see a drug approval. So, we can expect, hopefully in the next couple of years, to see many more drugs available on the market to treat patients with myelofibrosis. Some of those include agents that block different pathways within a cell. And that includes a drug called parsaclisib. There’s a drug called pelabresib (CPI-0610), which is a BET inhibitor.  

There’s another drug called navitoclax (ABT-263), which is a cousin of venetoclax (Venclexta), which is a drug that we’ve been using a lot in leukemia. So, there’s lots of different drugs that are being used in combination with ruxolitinib. There’s also a drug called luspatercept (Reblozyl) that’s also been approved for myelodysplastic syndromes. And I suspect that that’ll be approved as well to help patients with anemia. So, really, there’s lots of drugs that are being studied right now. And I think the question that we’re all asking is, well, how are we going to use all of these different drugs? So, I look forward to seeing the results of those studies.  


Mm-hmm. Will some drugs work better for some patients and others not? 

Dr. Hobbs:

That is such a good question. And so, what I’m hoping to see is exactly that. I’m hoping to see that for patients, for example, with anemia, perhaps we’re going to be using luspatercept and momelotinib. Perhaps we’re going to see that patients with certain mutations may respond better to certain medications like the BET inhibitors or navitoclax or the PI3 kinase inhibitor, parsaclisib. But as of now, we don’t have enough information.  

We haven’t seen enough results of these studies to start to be able to know, you know, what is the patient that’s going to do better with two drugs versus one drug? And so, I think that over the next couple of years we’re going to start to have answers to those questions.  

An Overview of ET, PV and MF Treatment Options

An Overview of ET, PV and MF Treatment Options from Patient Empowerment Network on Vimeo.

Treatment for essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF) can vary greatly. Dr. John Mascarenhas breaks down the treatment types and the goals of treatment for each type of myeloproliferative neoplasm (MPN).

Dr. John Mascarenhas is Associate Professor of Medicine at the Icahn School of Medicine at Mount Sinai (ISMMS) and the Director of the Adult Leukemia Program and Leader of Clinical Investigation within the Myeloproliferative Disorders Program at Mount Sinai. Learn more about Dr. Mascarenhas, here.

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Katherine Banwell:

Depending on the patient, it seems like ET or PV may be easily managed. So, how are they treated? Let’s start with essential thrombocythemia or ET.

Dr. Mascarenhas:       

So, ET is a disease in which first and foremost, we’re trying to reduce the risk of thrombosis, clotting, and/or hemorrhage bleeding. So, typically, ET patients are risk stratified by low risk or high risk.

It’s almost simply based on their age, whether they’ve had a clot in the past, and some systems now even incorporate other factors like mutation status. And, you tailor the treatment based on their risk score. So, low risk ET patients don’t necessarily need to be treated. They can be followed expectantly and watched. The height of the platelet count does not predict thrombotic risk. So, we don’t treat the platelet count per se. A high-risk patient is at high risk for clotting. So, these patients almost invariably are getting aspirin at a baseline, and they are often on cytoreductive therapy. And sometimes, that is chemotherapy like hydroxyurea. Sometimes it’s a non-chemotherapeutic option and like anagrelide, and sometimes it’s a biologic therapy like interferon alfa either 2a, Pegasys, or 2b ropeginterferon. And, these are therapies that have rationale, that have clinical data, that have demonstrated reduction in risk of clotting, which again is the reason why we treat high-risk ET patients.

Katherine Banwell:                  

And, what about PV, polycythemia vera?

Dr. Mascarenhas:     

So, in polycythemia vera, it’s similar to ET. We risk stratify patients low and high risk based on age and clotting histories. And whether you’re low or high risk, we give PV patients aspirin or at least once daily, and we look to keep their hematocrit below a threshold of 45 percent. And sometimes in women, we even go lower, to 42  percent. But the idea is that controlling the hematocrit, which is one of the red blood cells indices, you reduce the risk of having clots, and that’s been shown actually many years ago and reinforced in a very well-known study called the CYTO-PV study in Italy documented that if you keep the hematocrit less than 45 percent, so, stringent control versus allowing for less stringent control between 45 to 50, that you reduce by fourfold the number of cardiovascular events that can occur.

So, we know that controlling the hematocrit is important, and that can be done, again, with hydroxyurea, interferon, and ruxolitinib.

The JAK2 inhibitor has also proved specifically for patients who had an intolerance or refractory hydroxyurea, but also importantly as a drug that can address, probably better than most drugs in this field, the symptom burden that could be problematic for some of those patients. But, it’s really about controlling the hematocrit.

Katherine Banwell:                  

Yeah. Since myelofibrosis is a progressive condition, I imagine that makes it more difficult to manage. So, what else is available for patients with myelofibrosis?

Dr. Mascarenhas:       

The first line of treatment is typically a JAK inhibitor, although I would say that there are a subset of patients – well, there are patients we sometimes meet that have very low risk disease. They don’t have those clinical variables we discussed before that could uptick their risk score, and some of those patients can be watched.

And interestingly, there are a subset of patients that can have an indolent or slow form of the disease where they don’t have aggressive changes in their disease, their blood counts, their symptoms, their spleen, and don’t need immediate treatment. Most patients would benefit from a JAK inhibitor, although there are a subset of patients where their issue is less simple in spleen burden and it’s more anemia.

So, we take those patients where anemia’s the focus, we look at their erythropoietin level, which is their endogenous hormone level that regulates red blood cell production. If it’s low, we give them a lab-based form of erythropoietin, something called Procrit or Aranesp. If it’s high, we will move on. We can use a drug called danazol, which is a synthetic male androgen which can improve hemoglobin levels in 20 to 40 percent of patients. Or, we can use a drug called lenalidomide, which is an immunomodulatory drug. And, more recently, there’s a drug in testing called to luspatercept, which is an active activin receptor ligand trap. So, there is a growing armamentarium of drugs that can be used to try to alleviate the anemia which is present and can be a significant issue in about a quarter of patients with myelofibrosis upfront at time of diagnosis or about 75  percent through the course of their disease. So, that’s an unmet need that still requires attention and may alter the treatment plan for a given patient.

Katherine Banwell:                  

What about stem cell transplants?

Dr. Mascarenhas:       

So, we relegate stem cell plant transplants for those patients as mentioned before that are higher risk because we think that the potential benefit-to-risk ratio is in favor of transplant.

Transplant is really a modality that is the only modality that offers the potential for cure, but it’s also a modality that poses a significant risk of morbidity and mortality associated with it. So, it has to really be taken very seriously. It can’t be the kind of treatment you would think of as a last resort at the last minute. Once you see a transplanter, if they’re interested in that therapy and see it early on in the disease course, in my opinion, to start that dialog and then figure out when is the optimal time to employ a bone marrow transplant, which is not a surgical procedure. It’s often thought to be surgical. It’s not a transplant of an organ. It’s a transplant of hematopoietic cells. So, it’s really an infusion of stem cells that then end up in the person’s bone marrow, and they create a whole new hematopoietic system and immune system. And with that, you can have an immune system that then goes after the myelofibrosis stem cells.

That’s called graft-versus-leukemia effect. But with that included graft-versus-host disease, which is when the new graft, the new immune system doesn’t always recognize well the person’s own tissues, whether it’s the liver, or the lung, or the skin, and you can have immunologic reactions to that.

So, that’s a complex discussion. But, transplant, typically for patients less than 70 years of age who have high-risk myelofibrosis or even up to 75 if they have a good performance status and as we said don’t have a lot of comorbid issues with a goal of cure. So, if you have someone where their goal is to try to maximize their time out of the hospital and they’re not focused on longevity, their focused on quality of life, that may not be an appropriate patient for transplantation.

So, I think a very upfront, honest and a transparent discussion with the patient about what to expect with transplant, what are the pros and cons, what are the risks involved, and importantly does it match up with their expectations or their desires.

Promising ET, PV & Myelofibrosis Therapies in Development

Promising ET, PV & Myelofibrosis Therapies in Development from Patient Empowerment Network on Vimeo

MPN specialist, Dr. Srdan Verstovsek discusses the latest research and progress for the treatment of patients with essential thrombocythemia (ET), polycythemia vera (PV) and myelofibrosis (MF).

Dr. Srdan Verstovsek is Chief of the Section for Myeloproliferative Neoplasms in the Department of Leukemia at The University of Texas MD Anderson Cancer Center. Learn more about Dr. Verstovsek, here.

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Dr. Srdan Verstovsek

When we talk about the new therapies in development, there are many in myelofibrosis in particular, and a few are in essential thrombocythemia and polycythemia vera. Let’s start with ET and PV. Here we are expecting either studies, or possibly even approval, of a long-acting interferon called Ropeginterferon that was approved a year ago in Europe for PV patients.

We gonna have, hopefully here in the United States, that drug for our patients in a year or perhaps studies in PV, or perhaps most definitely, I would say, studies in ET with this drug. That would be enhancement of what we done off-label using interferons that are approved for some other conditions. We know that interferons are biological agents active in these conditions to control the bone marrow, and perhaps even decrease the number of malignant cells in the bone marrow of patients with ET and PV, which may be beneficial down the road.

In myelofibrosis, the picture is completely different. In this setting, the life expectancy, unfortunately, is affected as we discussed, and we need therapy that would be perhaps improving that life longevity. As we know, the ruxolitinib JAK inhibitor that has been around for nine years can extend the life a few years, but not cure people.

So, helping JAK inhibitors by combinations with other active agents that would be biologically modifying that bone marrow, decrease the tumor burden, improving the quality of life or anemia, are at forefront of what is happening right now. So, combinations with Navitoclax which is Bcl-xL cell inhibitor, CPI-0610, which is BET inhibitor, Luspatercept which is anemia drug.

These are phase three studies that are planned to start soon for possible approval for combinations over JAK inhibitor alone for different problems that people face.

Or, later on in the course of the disease, JAK inhibitor may fail. What do you do then? So, we have studies announced that will be done in what we call a second line, after-JAK inhibitor. And the MDM2 inhibitor was announced. Imetelstat inhibitor in the second line. Momelotinib JAK inhibitor in the second line. Fedratinib is being studied, another JAK inhibitor. Pacritinib for patients with low platelets

These are all phase three studies. That’s means for approval of this drug, so that will be three and four, seven different phase three for myelofibrosis patients with different clinical scenarios, different clinical problems are being done, or about to be done, in very near future. So, my prospect is here. My view on that is that we will have, hopefully, at least some of these seven studies leading to approval of some new drugs for our patients with myelofibrosis.