Nicolaus Kröger, MD, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, outlines the use of the JAK inhibitors ruxolitinib and fedratinib in patients with myelofibrosis, prior to stem cell transplantation (SCT). These JAK inhibitors have demonstrated an ability to reduce spleen size and constitution symptoms. Prof. Kröger summarizes the findings of a large study analyzing data from 500 patients, which investigated whether ruxolitinib treatment before SCT had a beneficial impact on patient outcomes. The study found that patients who received and responded to ruxolitinib before SCT had improved outcomes compared to those who did not respond to ruxolitinib and those who were not treated with ruxolitinib. This interview took place during the 47th Annual Meeting of the European Group for Blood and Marrow Transplantation (EBMT) 2021.
So, myelofibrosis becomes a more clinical indication, the number for stem cell transplantation in myelofibrosis are steadily increasing. More recently, JAK inhibitors, mainly ruxolitinib and more recently fedratinib, has been approved as a treatment for myelofibrosis. So, this JAK inhibitor reduced spleen size and improved constitution symptoms. And many investigators in the last year tried to include JAK inhibitors in the transplant concept, especially by reducing the spleen size and improving constitution symptoms prior to stem cell transplantation. However, we were not sure whether this is a beneficial approach or not, and randomized studies are not undertaken so far.
So, within EBMT in a large study looking for 500 patients, we looked whether ruxo pre-treatment has some beneficial after the outcome after stem cell transplantation. So, if you compare ruxo versus no ruxo, there is only a trend for improved event-free and overall survival. However, if you look more in details, those patient who are responding to ruxo and then received stem cell transplantation while they are still in remission or in response to ruxo, then they have a favorable outcome regarding relapse, but also event-free survival. But if patient had received ruxolitinib, but failed or were resistant before they go to transplantation, then the transplant outcome is similar to those who never received ruxo prior to transplantation.
So, this is in favor or in line with other arguments suggesting if you use ruxo prior to transplantation, you should go for transplantation while patient is in a responsive stage. It means the spleen is low and improvement of constitution symptoms. And this will also present at this meeting.