Treating Post-MPN Acute Leukemia Remains an Unmet Medical Need

Gabriela Hobbs, MD

Post-myeloproliferative neoplasm (MPN) acute myeloid leukemia is a rare disease, meaning there are many unmet needs for this patient population.

According to Gabriela Hobbs, MD, the clinical director of Leukemia Service and assistant in Medicine at Massachusetts General Hospital, there are not many clinical trials specifically designed for this group of patients. Most clinical trials that enroll this population are aimed at treating acute myeloid leukemia (AML) in general.

Some progress has been seen with targeting IDH mutations. However, more information is still needed on why these post MPN disease develop.

In an interview with Targeted Oncology^TM, Hobbs discussed the current treatment landscape for MPNs and the research that is aiming to address post-MPN acute leukemia and unmet needs for the patient population.

TARGETED ONCOLOGY™: Are there any ongoing clinical trials in the post-MPN acute leukemia space?

HOBBS: Post myeloproliferative neoplasm acute leukemia is a pretty rare entity, so, most of these studies that are aimed at treating this condition are similar to the trials that are aimed at treating acute myeloid leukemia in general. [There has been some] utilization of medications to treat a mutation called IDH, which is something that can occur rarely in patients with myeloproliferative neoplasms but has been very important in treating acute myeloid leukemia. But otherwise, unfortunately, there aren't many clinical trials that are aimed specifically at treating this patient population separately.

Can you summarize what the treatment landscape looks like right now for patients with post myeloproliferative neoplasm acute leukemia?

So, patients with post myeloproliferative neoplasms, whether that comes myelofibrosis related leukemia, or acute leukemia, don't really have what's considered a standard of care for treatment. Because, like I mentioned before, this is kind of a rare condition. The goal is to get patients into remission. We know that long term survivors really have to get a bone marrow transplant. And so how to get to transplant is something that's still an area of active investigation. And that can either be with lower intensity regimens, including the site of vineries with ruxolitinib, as was demonstrated in the Myeloproliferative Disease Research Consortium Study, or it can be with more intensive therapies like one would use for acute myeloid leukemia. But really the ultimate goal is to get patients to a transplant once they achieve a remission in order to achieve longer term remission.

What are some of the other unmet needs right now that is being addressed in clinical trials?

I think the first thing is just to have more dedicated clinical trials for this group of patients, which is difficult because there aren't that many of these patients. Any clinical trial that does happen for this disease group would need to be a multicenter study. That, I would say, the biggest unmet need. And then, I think additionally, is further understanding of the genetics and the biology of post myeloproliferative neoplasms, acute leukemia, to help us to better design trials that treat the mutations that these patients have.

One thing that's important to highlight is although patients with essential thrombocytosis and polycythemia vera are usually thought to have indolent hematologic malignancies. It's important to remember that these rare complications like transformations to myelofibrosis, and transformation to leukemia actually do happen. So, even though they don't happen frequently, we need to just remember that they do happen so that we're able to recognize them… And so, if you're not looking for transformation, you may miss it. It may make a big difference in how these patients ultimately end up doing.