PharmaEssentia Corporation announced the publication of new results from a Phase 2 clinical study with ropeginterferon alfa-2b (marketed as BESREMi®) for the treatment of patients with polycythemia vera (PV). This study, which was conducted in China, demonstrated the efficacy and tolerability of ropeginterferon alfa-2b using an alternate dosing regimen that has a higher starting dose and a more rapid dose titration as compared to current U.S. label dosing. The publication, titled “A new dosing regimen of ropeginterferon alfa-2b is highly effective and tolerable: findings from a phase 2 study in Chinese patients with polycythemia vera,” was published in Experimental Hematology & Oncology and co-authored by PharmaEssentia researchers.

PV is the most common myeloproliferative neoplasm (MPN) and a long-term, potentially life-threatening disease with limited approved treatment options. Patients with PV are at an increased risk of developing thromboembolic events due to increased blood cell counts and have a long-term risk of progression to myelofibrosis or transformation to acute myeloid leukemia.1 Per current label dosing, the recommended starting dose of ropeginterferon alfa-2b is 100 µg, with dose increases of 50 µg every two weeks until hematologic parameters are stabilized (up to a maximum dose of 500 µg).2 The intention of this study was to assess whether ropeginterferon alfa-2b treatment at a starting dose of 250 µg, followed by 350 µg two weeks later and then 500 µg from week 4 onwards could achieve faster and improved clinical efficacy within 24 weeks of treatment with acceptable tolerability. The study included 49 patients with PV with resistance or intolerance to hydroxyurea.

Key findings included: The complete hematologic response (CHR) rate at week 24 (61.2%) was notably higher than that at 12 months previously observed in the PROUD-PV study and a Phase 2 study by Edahiro et al. (43.1% and 51.7%, respectively), both of which used the current labeled dose titration schedule.3,441 out of 48 patients who completed the studyi (85.4%) saw a reduction in JAK2V617F allele burden. Ropeginterferon alfa-2b was generally well-tolerated in this study.

Adverse events (AEs), which were mostly mild or moderate, were reported in 48 out of 49 patients. The most common AEs with an incidence?=?10% included an increase in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with the majority being grade 1 or grade 2. Long-term treatment and follow-up of the patients in the study are planned to assess progression-free and overall survival.