Martin Griesshammer, MD, PhD, from the Johannes Wesling University Clinic, spoke on the current unmet needs in treating polycythemia vera (PV) and how multistakeholder collaboration can help address them.
Martin Griesshammer, MD, PhD, professor and medical director of the Department of Haematology, Haemostaseology, Oncology, and Palliative Care at the Johannes Wesling University Clinic, at the European Hematology Association 2023 Congress in Franfurt, Germany.
What are the current unmet needs in the treatment of PV and what can be done to address them?
There are several unmet needs in polycythemia vera. First, we know that neither phlebotomy nor hydroxyurea therapy really improves symptoms. So, improving symptoms is an unmet medical need and only with the new treatments, interferon and ruxolitinib, we really can improve the symptoms.
Other questions are what about the reduction of the JAK2 [janus kinase 2] allele burden. So, this is also an unmet medical need. We cannot reduce the JAK2 allele burden with neither hydroxyurea nor phlebotomy. So, only the new therapies are able to reduce the allele burden and with a MAJIC PV trial using ruxolitinib, we are well aware that only these drugs, ruxolitinib and interferon, are able to reduce the allele burden with a positive effect for the pathophysiology of the disease.
How can current treatment strategies being improved to achieve better disease control in PV?
The disease control is established by clear definitions of treatment failure. So, in the ELN [European LeukemiaNet criteria], many years ago, we had established a clear definition of treatment failure that means resistance or intolerance, to especially hydroxyurea. So, using these definitions will help to lead the way to the correct therapy.
What does treatment failure look like in patients with PV and what is the optimal treatment strategy when first-line treatment fails?
Well, treatment failure is either resistance to a therapy, mostly hydroxyurea, or intolerance. So, let us start with intolerance. Intolerance means that, for example, you get side effects like ulcers with hydroxyurea or skin problems or other side effects. Another intolerance means that you get cytopenia. So, cytopenia with conventional drugs means also a failure of therapy.
The other thing is resistance. So resistance, for example with hydroxyurea, means that you have to additionally establish therapies plus phlebotomy in addition to hydroxyurea to achieve the hematocrit below 45%.
What collaborative efforts are needed among health care professionals, researchers, and industry stakeholders to address the remaining unmet needs in treating PV?
Well, PV is a disease with a multifaceted spectrum. So, for example, we have a lot of thrombotic issues, cardiovascular issues, dermatology issues, especially with hydroxyurea. So all these specialties have to work together to get the best therapy for the patient.