Experts in polycythemia vera review data regarding the role of symptomatic improvement in overall outcome in patients with polycythemia vera.
Prithviraj Bose, MD: Back to our case: the patient is started on ruxolitinib 10 mg twice daily. This is the starting dose in PV [polycythemia vera]. It’s not based on platelet count, as it is in MF [myelofibrosis].
Let’s move on to an interesting and slightly different study: the RELIEF trial. Ruben, this is a study that you led. It is a phase 3B study with 110 patients: 54 and 56 in 2 groups. These are patients who were on Hydrea and had their counts controlled, but the symptoms were persistent. This was a very specific population trying to answer a very specific question. Reporting symptom counts controlled with 54 and 56 in the 2 arms: ruxolitinib or continue Hydrea. The primary end point was the TSS cytokine cluster, which is itching, fatigue, muscle aches, night sweats, and sweats while awake. This particular study, at least at 16 weeks, did not achieve the primary end point of statistically significant reduction in the TSS cytokine cluster. The P value was .139. But later on, after that 16-week time point, ruxolitinib provided greater benefits than patients who continued hydroxyurea. Adverse effects were fairly minimal in this trial. There was nothing new or surprising.
This has been alluded to the REVEAL study that Dr Brady Stein had an oral presentation on at ASH [American Society of Hematology Annual Meeting] 2020. One aspect of the study is a noninterventional observational study that’s been going on for a few years. It has about 2510 patients enrolled, so this is a large study. It’s the largest prospective PV study in the United States. It focuses on observing patients’ usual care with no interventions being made. This was a large and rich data set, showing, for example, how many were getting Hydrea, what dose, and whether they had 1, 2, or all 3 counts controlled. All these different percentages and proportions are available from the baseline characteristics.
Here are some interesting findings. We’ve already alluded to the survival thing. Although the median age was 66 at study entry, more than 10% of these patients had passed away at 4 years. Ruben and Stephen, this is the point you both were making earlier; not everyone does well. Some other interesting points from this study were that there did not appear to be a correlation between the symptom control and the number of counts controlled or which counts were controlled. They nicely showed, according to 1, 2, or all 3 counts controlled, that the symptom burden did not seem to defer as I see it. Similarly, they made the same observation when they looked at specific symptoms like fatigue, inactivity, concentration issues, itching, and early satiety. There was not much of a correlation with the blood count control.
Finally, there is something to be aware of and not necessarily something that should make us change our practice. We observed patients who were on aspirin and an anticoagulant for a clot that they had, which is fairly standard practice. PV is a risk that’s never going to go away, so we usually consider that an unprovoked clot and we put them on anticoagulation. But this observational study showed that the bleeding risk was significantly increased in those patients on a blood thinner and aspirin.
Ruben Mesa, MD: That was a fantastic discussion of the data. As we chat about each of the 3 MPNs [myeloproliferative neoplasms], we’ll be able to compare and contrast a bit with that fantastic base of information from polycythemia vera.
This transcript has been edited for clarity.