EHA 2023 | Safety and anemia outcomes with momelotinib vs pacritinib in patients with myelofibrosis

That’s one of the abstracts we are presenting here at the EHA this year. So, it is a matched-adjusted indirect comparison of published data of momelotinib study, including SIMPLIFY-1, SIMPLIFY-2 and MOMENTUM and studies of pacritinib that included the 200mg dose, such as PERSIST-2 and PAC203 which was the dose finding study. And actually what happened is we compared the safety outcomes as well as anemia outcomes from a pool data of these studies. They were reweighted for they, they kind of create a comparable cohort. The matching included the baseline characteristics such as risk score DIPSS, then baseline anemia, thrombocytopenia, or platelet numbers, then spleen size, TSS and then basic demographics such as age, sex, percentage of males and so forth, and so on. Patients in these cohorts were well matched for this particular study. What I was mostly interested in was the degree of anemia as well as thrombocytopenia, they were well correlated in between the cohorts. For about 40% of patients represented patients with anemia or transfusion dependency, and about 60% of patients represented hemoglobin below ten. And then severe thrombocytopenia, we have approval of pacritinib, has been about 40% in all of these cohorts. So very well-balanced groups that were then compared for safety outcomes that were reported in 50% or more of patients on these studies and then anemia outcomes that included the improvement of hemoglobin by 1 or 2g or dL at 24 weeks, and then clinical improvements of anemia, which is defined as improvements of 2g or more that lasts for eight weeks and then excludes time after transfusion or a time with transfusion independency that lasts over eight weeks.

So doing this comparison actually the results came as momelotinib showed favorable safety profile for odds as well as risk differences for anemia grade three or four, thrombocytopenia grade three or four, as well as key gastrointestinal side effects such as diarrhea, vomiting, nausea, peripheral edema and the degree of serious adverse events as well as grade three and grade four adverse events. The same analysis then was done for anemia and actually what we’ve seen was comparable: momelotinib was favorable for clinical improvements of anemia as well as anemia improvements by one gram when compared from these studies over pacritinib. So, and so given the limitations of the studies which include just comparison of available data, inconsistencies in data, different reporting, different definition, we kind of saw that momelotinib provided a favorable safety profile as well as anemia improvements in patients with myelofibrosis, that included those with JAK inhibitor-naive as well as JAK inhibitor-exposed patients, and that may represent a very favorable or desired options for these patients as a therapy.