Published on August 28, 2020
What's the Latest Treatment News and Available Clinical Trials for Essential Thrombocythemia?
What clinical trials are available for MPN patients with essential thrombocythemia (ET)? Are there new treatments for ET in development? In this segment from a recent MPN Answers Now program, host Andrew Schorr gets answers to these questions plus more from Dr. Ellen Ritchie from Weill Cornell Medicine.
This is Part 3 of a 4-part series. Watch the complete series below:
- Part 1: What Essential Thrombocythemia Treatments Are Available?
- Part 2: Essential Thrombocythemia and COVID-19 Complication Risk
- Part 4: Can Diet and Exercise Help Essential Thrombocythemia?
This program is sponsored by Bristol Myers Squibb. This organization has no editorial control. It is produced by Patient Power. Patient Power is solely responsible for program content.
Transcript | Current Research on Essential Thrombocythemia
Treatment Developments for Essential Thrombocythemia
Okay, let's talk about research. You mentioned that it's difficult to do in ET, but still, what could be something new that you start talking about in ET? Where are we headed?
Well, I think that the value of interferon is still an important topic in myeloproliferative diseases in general, and there was recently a very interesting Phase III trial looking at polycythemia vera and the treatments of patients with ropeginterferon, which is less frequently given than Pegasys, which is the interferon we commonly use in the United States… where it showed that patients with long term follow-up with PV had an ongoing, continuing improvement in their response, both of their blood counts and of the molecular signature of their disease; their JAK2 allele burden went down progressively over a three-year period.
At one year, hydroxyurea (Hydrea) and Pegasys looked very similar, but at three years, that using ropeginterferon showed an ongoing crystallization of their response. This is probably true in essential thrombocythemia, also, but will need to be proven, but I think that makes it a very exciting agent that would potentially replace all of these other agents I talked about as a front-line treatment for essential thrombocythemia in patients who need cytoreduction.
So, I think that's very important. Ropeginterferon has not been approved yet in the United States. This is something that will be hopefully approved eventually in the United States, but the value of treating patients with essential thrombocythemia... I think that that will be something that the community will want to establish.
What about bomedemstat, and she said it's an LSD1 inhibitor?
Oh, the LSD1 inhibitors, I forgot to talk about those. Yes, those are also-
Calls it IMG-7289... so, wanted to know more. Is there currently a trial for this drug?
Yes, there are clinical trials for the LSD1 inhibitors run by Imago Therapeutics, and they are clinical trials looking both at primary myelofibrosis and essential thrombocythemia. These also are very promising targets in essential thrombocythemia, and we'll have to see what the trials show, but the LSD1 inhibitors are a very interesting target.
What Should ET Patients Know About Clinical Trials?
Okay, let's talk about just being in a clinical trial for a minute. So if somebody is just on baby aspirin and things are going okay, they might say, "Well, if it's not broken, don't fix it," so who are the ET patients where these uses of drugs that are used otherwise in MPNs or in clinical trials for other MPNs, or like what you just mentioned, new classes of drugs... where maybe they should be talking to their doctor about a trial?
I think any patient with ET who requires cytoreduction, and even a patient who has a very low-risk disease and their doctor has said that they should go on a baby aspirin... there are clinical trials looking at that, as well. So, I think talking to a specialist who is operating clinical trials for ET is reasonable in every single case. There is no real standard of care for upfront treatment for essential thrombocythemia, so if there is a clinical trial and you are in need of cytoreductive therapy, I think it's reasonable to put yourself forward as a candidate.
It's really important in diseases like ET; these are rare diseases. It's very difficult to find the patients to enroll on clinical trials to allow us to get the answers we need to move the field forward, so it's important for patients to participate if they can in a clinical trial, because it not just benefits them, but it allows us to learn a lot more about these diseases and how to best treat them in the future.
So, Dr. Ritchie, in myelofibrosis, there's some people who have a stem cell transplant... that's a big gun, and it has morbidity, I think, that can go with it, as you say. Does that have any role for anybody with ET?
Not for ET. If you develop post-ET myelofibrosis and you become very ill with that, it is reasonable to think about a clinical trial or having a stem cell transplant, but a stem cell transplant has a great deal of morbidity and mortality. There is an upfront mortality risk of 20 percent, and with a bone marrow transplant, and a five-year overall survival that's probably less than 50 percent. So, that's not something that you do unless you have a disease which is definitely fatal.
One last thing about clinical trials: we have people around the world who watch these programs, and so we talked about different trials, and they say, "Well, can I be in a trial in another country?" The answer is often yes, right?
Absolutely. Clinical trials are offered worldwide, so whether you live in Europe or Asia, or the United States, or South America, or Central America, there are clinical trials in your countries, and you should be able to participate.
So I developed primary myelofibrosis, and I know my friends with ET don't want to go there, although I am doing well on one of the JAK inhibitors. But people with ET understand there can be progression; is there any research that can slow the progression of ET to other MPNs, polycythemia vera or myelofibrosis?
Well, there's some data to suggest that the interferons may actually slow the progression to myelofibrosis. These are small pieces of data. We need larger studies to sort of validate that, but it echoes what we've seen in the recent polycythemia ropeginterferon trial, which suggests that there is a deepening of response as the longer that you're on the drug, and if that is actually happening, that that probably would delay the development in myelofibrosis.
There has been no drug which has been shown to stop the development of acute leukemia in patients who are going to be prone, who have myelofibrosis or have any of the other MPNs, but it may be possible to delay myelofibrosis. Patients can live with ET for a long time without developing myelofibrosis. I just saw an ET patient the other day who has been diagnosed for 30 years and has not progressed to myelofibrosis yet, so that's a long time. And so, I think that the timeline for each person is slightly different, and that there is hope that there are some drugs we already have that may play a role in deferring the transition to other MPNs.
Okay, so just to tie it all together, Dr. Ritchie, it sounds like for ET patients, while there may be an individual situations that you have a variety of ways to handle it in a personalized way, and that with exercise, diet, right medicine... maybe being in a clinical trial... that people can live-
And not smoking... people can live pretty well.
All right. Well, hopefully, that lessens the emotional burden people have now.
Please remember the opinions expressed on Patient Power are not necessarily the views of our sponsors, contributors, partners or Patient Power. Our discussions are not a substitute for seeking medical advice or care from your own doctor. That’s how you’ll get care that’s most appropriate for you.