Targeted Oncology: What was the make-up of the PERSIST-2 trial (NCT02055781) looking at pacritinib (Vonjo) in patients with myelofibrosis (MF)?
JOHN MASCARENHAS, MD: This was the more interesting of the 2 PERSIST studies. PERSIST-2 looked at patients with platelets of 100,000/µL or less.1 So, the cytopenic patient with MF could have been given a Janus kinase [JAK] inhibitor before being enrolled, and half did in this study…but these are patients that were hard to treat, which was opposite to the set-up of the COMFORT-1 [NCT00952289] and COMFORT-2 [NCT00934544] studies.2 [Patients in PERSIST-2 study] were given either 400 mg daily or 200 mg of twice daily pacritinib vs patients on best available therapy [BAT], which could also include ruxolitinib [Jakafi], with a coprimary end point of spleen volume reduction of 35% or more and reduction of the total symptom score at week 24.1
What stood out among patients enrolled in either arm of the study?
I think what’s important to appreciate is when asking the investigator what they would give to patients who were randomly assigned to the BAT arm is that there is a lack of options available. In the BAT arm, 45% of patients got low-dose ruxolitinib, 19% had no options, while some patients were getting hydroxyurea [19%], steroids [13%], and even interferons [2%], which I would argue don’t work in this setting.1 These were patients who had higher-risk disease, and half of them had hemoglobin counts less than 10 g/dL, and the median platelet count was somewhere around 50,000/µL [in a majority of patients in both arms].