The FDA has approved ropeginterferon alfa-2b-njft (Besremi®, PharmaEssentia) for patients with polycythemia vera, marking the first approval of interferon therapy specifically for patients with polycythemia vera and the first treatment for all patients with polycythemia vera, regardless of their prior treatment history.
"Ropeginterferon alfa-2b is a novel long-acting monopegylated IFN-alpha-2b," wrote Heinz Gisslinger, MD, Professor of Hematology at the Medical University of Vienna, Austria, and colleagues, in their publication of the PEGINVERA trial (NCT01193699), on which the approval was based. "Due to reduced dosing frequencies, better tolerability, and improved compliance, ropeginterferon alfa-2b may be a favorable treatment option for long-term therapy in patients with polycythemia vera."
The phase 1/2, multicenter, single-arm trial enrolled 51 patients with polycythemia vera, who received ropeginterferon alfa-2b for an average of five years. The primary end point was complete hematological response, which required that patients have a red blood cell volume of less than 45% without a recent phlebotomy, normal white cell counts and platelet counts, a normal spleen size, and no blood clots. Overall, 61% of patients receiving ropeginterferon alfa-2b experienced a complete hematological response.
Adverse reactions occurring in more than 40% of patients receiving ropeginterferon alfa-2b in clinical trials included influenza-like illness, arthralgia, fatigue, pruritus, nasopharyngitis, and musculoskeletal pain. Additional potential adverse reactions may include elevated liver enzymes, decreased white blood cells, low platelet levels, joint pain, fatigue, itching, upper airway infection, urinary tract infection, depression, transient ischemic attacks, and neuropsychiatric, autoimmune, ischemic, or infectious diseases. Patients with a severe psychiatric disorder, certain autoimmune diseases, or liver disease should not receive ropeginterferon-alfa-2b.
"These data provide evidence that treatment with ropeginterferon alfa-2b for up to 7 years is efficacious, well tolerated, and disease modifying," concluded Dr. Gisslinger and colleagues in their November 2018 publication of the PEGINVERA results in Blood.
The recommended starting dose of ropeginterferon alfa-2b for patients with polycythemia vera is 100 mcg by subcutaneous injection every two weeks and 50 mcg for patients receiving hydroxyurea. Afterwards, the recommended dose is increased by 50 mcg every two weeks, up to a maximum of 500 mcg, until hematological parameters are stabilized.
For More Information
Gisslinger H, Buxhofer-Ausch V, Thaler J, et al (2018). Long-term efficacy and safety of ropeginterferon alfa-2b in patients with polycythemia vera — final phase I/II Peginvera study results. Blood (ASH Annual Meeting Abstracts), 132(suppl_1). Abstract 3030. DOI:10.1182/blood-2018-99-118584
Clinicaltrials.gov (2018). Safety study of pegylated interferon alpha 2b to treat polycythemia vera (PEGINVERA). NLM identifier: NCT01193699.
Image credit: The Armed Forces Institute of Pathology (AFIP). Licensed under public domain