Alternative Dosing Regimen of Ropeginterferon Alfa-2b Demonstrates High Efficacy, Tolerability Among Patients With Polycythemia Vera

Ropeginterferon alfa-2b at a new, alternative dosing regimen of 250-350-500 μg was found to be highly effective and well-tolerated among patients with polycythemia vera, according to a phase 2 study published in Experimental Hematology & Oncology. 

This new regimen “can help patients achieve greater and rapid complete hematologic and molecular responses,” according to Jie Jin, MD, and Lei Zhang, MD, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China, and co-authors. 

Ropeginterferon alfa-2b is a new-generation pegylated interferon-based therapy and is administered every 2 to 4 weeks. This treatment is currently approved for patients with polycythemia vera (PV) in the United States and Europe, at a starting dose of 100 µg (50 µg for patients receiving hydoxyurea) and intra-patient dose titrations up to 500 µg at 50 µg increments, which take around 20 or more weeks to reach a plateau dose level. 

This study aimed to assess ropeginterferon alfa-2b at an alternative dosing regimen, which consisted of a higher starting dose and quicker intra-patient dose titrations: the 250-350-500 μg schema. The phase 2 trial included 49 Chinese patients with PV with resistance or intolerance to hydroxyurea.

The primary end point was the complete hematologic response rate, which at week 24 was found to be 61.2%. This response rate was higher than the rate with the approved dosing schema of 43.1% at 12 months. The JAK2V617F allele burden decreased from baseline to week 24 (17.8% ± 18%), with 1 patient achieving a complete molecular response.

Overall, this dosing regimen of ropeginterferon alfa-2b was well-tolerated in patients, and most adverse events were observed to be mild or moderate. Common adverse events included alanine aminotransferase and aspartate aminotransferase increases, though these occurred mostly at grade 1 or 2 levels. Patients did not present with jaundice or significant bilirubin level increase. There were 7 patients (14.3%) who experienced reversible, drug-related grade 3 adverse events. Notably, there were no grade 4 or 5 adverse events, and no adverse events that led to treatment discontinuation. 

“Ropeginterferon alfa-2b at the 250-350-500 μg regimen is highly effective and well-tolerated and can help patients achieve greater and rapid complete hematologic and molecular responses,” the study authors concluded. 

Source: 

‌Jin J, Zhang L, Qin A, et al. 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. Exp Hematol Oncol. 2023;12(1):55. doi:10.1186/s40164-023-00415-0