Efficacy and Safety of Peginterferon Alfa-2b in 95 Patients with Myeloproliferative Neoplasms:a Single Center Retrospective Analysis

Background Polycythemia vera (PV) and essential thrombocythemia (ET) are a common type of Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) driven by the JAK2,CALR or MPL mutation, which are associated with a reduced quality of life, a high rate of vascular events, and an intrinsic risk of disease evolution to myelofibrosis and acute myeloid leukemia. Pegylated interferon has obtained high-level evidence for short-term clinical trial endpoints such as hematocrit control, symptom burden/quality of life, splenomegaly, and JAK2 allele burden lies within the timeline of most studies.

Objective To investigate the efficacy and safety of Peginterferon alfa-2b in patients with myeloproliferative neoplasms

Methods The clinical data of 95 patients with MPNs treated with Peginterferon alfa-2b in Peking Union Medical College Hospital (Beijing, China) from January 2018 to May 2022 were retrospectively analyzed. Peginterferon alfa-2b was administered subcutaneously once weekly at a starting dose of 180ug, and could be decreased over time to 180ug every 2 to 4 weeks if hematological control was achieved. Hematological control was defined as HCT<45% in the absence of phlebotomy in patients with PV and PLT<400x10⁹/L in patients with ET. Molecular response was defined as JAK2 allele burden decreased＞50% from baseline (partial remission) or undetectable at a lower limit of quantitation at 1% by the central laboratory (complete remission) which was measured by next-generation sequencing

Results Among the 95 patients, 48 were male and 47 were female. There were 61 cases of PV and 34 cases of ET. The median age at diagnosis was 45 (17-69) years, and the median time from onset to diagnosis was 5.1 (0-413) months. All patients had next-generation sequencing for the driver mutations, there were 84 cases of JAK2 mutation, 8 cases of CALR mutation, 1 case of MPL mutation, and 2 cases of triple negative. The median duration of Peginterferon alfa-2b exposure was 13.2（2~51）months. 54 (88.5%) of 61 patients with PV achieved hematological control and 24 (70.6%) of 34 patients with ET achieved hematological control. The median onset of action was 1.4 (0.5-6.7) months. 47 patients with JAK2 mutation were detected with JAK2 allele burden for molecular evaluation. A total of 17 (36.2%) patients obtained molecular partial remission by 6 months and 26 (55.3%) patients achieved molecular partial remission by 12 months while no one achieved molecular complete remission. The most common treatment-emergent adverse events were influenza-like symptoms (88.4%), hyperglobulinemia (14.7%), elevated alanine aminotransferase (13.7%), and subclinical hypothyroidism (7.4%). A total of 4 patients (4.2%) discontinued the treatment, 2 due to intolerance of adverse effects, 1 due to disease progression to myelofibrosis, and 1 due to pregnancy.

Conclusion This study demonstrates that Peginterferon alfa-2b was safe, well tolerated, and efficacious in patients with PV and ET.

Keywords: Peginterferon alfa-2b, myeloproliferative neoplasms, hematological control molecular response

No relevant conflicts of interest to declare.