Dr. Mascarenhas: 
This is CME on ReachMD, and I'm Dr. John Mascarenhas. Today, I'm reviewing recently presented real-world data on the use of pacritinib for treating patients with myelofibrosis in the United States.

So the study I'm reviewing today was presented both at ASCO [American Society of Clinical Oncology] and EHA [The European Hematology Association] and is a retrospective look at real-world outcomes of patients with myelofibrosis, 142 to be specific, in the US that were treated between June of 2022 and August of 2023. So median time from diagnosis to treatment with pacritinib in this cohort of patients was about 13 months. Nearly 1/3 of these patients had platelet counts less than 50,000 and 1/3 had a hemoglobin less than 8 g/dL. And this data was all taken from the Integra-PrecisionQ database and included EMR [electronic medical records] practice management data.

If we get right to the data, what we see when broken down by lines of therapy, that pacritinib was most frequently used in first and second line of therapy, less so in third line of therapy. And then when looking at the platelet count thresholds in which pacritinib was used, it was more frequently used in the first line of therapy for platelets of less than 50,000 and more frequently used in latter lines of therapy in platelets greater than 100,000. Interestingly, pacritinib was more frequently used in patients with hemoglobins greater than 8 g/dL, both in the first and second line of therapy. And this is interesting because usually hemoglobin and platelet counts will trend and track together.

If you look at what happens to patients in terms of their platelet count and hemoglobin, I think very reassuringly and in line with the phase 3 data presented in the PERSIST-2 trial, there was stability in the platelet count and hemoglobin level over the follow-up time, which was about 6 months in this study. In fact, in the first 30 days, there was a slight increase in platelet count in those patients with platelets less than 100,000 at baseline and an improvement in hemoglobin in patients with hemoglobins less than 8 g/dL that endured and even improved further over time. So stability in platelet and hemoglobin over the treatment period with pacritinib in the real-world experience.

If you look at the survival of patients that were treated with pacritinib in this cohort of 142 patients, at 12 months, the probability of survival was 65%. This compares very favorably to multiple other studies looking at outcomes of patients with myelofibrosis at this point in their treatment algorithm. And when looking at patients with first-line pacritinib, the median survival was 77%. And looking at patients who had platelets less than 50,000, which is an adverse prognostic factor, the median survival was 75% at 12 months. And this didn't really change, even in the second line with pacritinib, and even with patients who had failed ruxolitinib prior to this, the 12-month overall survival was 65%.

So this really paints a picture, in totality, of a very well-tolerated drug that can be used first, second, or third line of therapy, even in patients with low platelets and hemoglobin, affording patients benefit and durable benefit and stability in platelet count, hemoglobin, and even survival in this very advanced patient population. So this was very reassuring from a real-world experience compared to randomized phase 3 prospective data at multiple centers.

And with that, I want to end our time. I hope this information was useful to you and your practice. And thanks for listening.