The Food and Drug Administration (FDA) has approved Besremi® (ropeginterferon alfa-2b-njft), an interferon alfa-2b, for the treatment of adults with polycythemia vera.
Besremi is a monopegylated, long-acting interferon, which exhibits its cellular effects in polycythemia vera in the bone marrow by binding to a transmembrane receptor termed interferon alfa receptor. This initiated a downstream signaling cascade through the activation of kinases, specifically Janus kinase 1 and tyrosine kinase 2 and activator of transcription proteins.
The approval was based on data from the open-label, prospective, multicenter, phase 1/2 PEGINVERA study (ClinicalTrials.gov Identifier: NCT01193699), which evaluated the efficacy and safety of Besremi in 51 adults with polycythemia vera for 7.5 years.
Findings showed that 61% (n=31/51; 95% CI, 46-74) of patients treated with Besremi achieved complete hematological response (defined as hematocrit greater than 45% and no phlebotomy in the preceding 2 months, platelets 400 x 109/L or greater, leukocytes 10 x 109/L or greater, and normal spleen size). The median duration of response was 14.3 months (95% CI, 5.5-30.1).
As for safety, the most common adverse reactions (greater than 40%) were influenza-like illness, arthralgia, fatigue, pruritus, nasopharyngitis, and musculoskeletal pain. Besremi carries a Boxed Warning associated with the risk of serious disorders, including aggravation of fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders.
Besremi is supplied as a 500mcg/mL single-dose prefilled syringe and is expected to be available by the first week of December 2021. The product is administered subcutaneously once every 2 weeks.
- US FDA approves Besremi® (ropeginterferon alfa-2b-njft) as the only interferon for adults with polycythemia vera. News release. PharmaEssentia Corporation. Accessed November 15, 2021. https://www.businesswire.com/news/home/20211112005909/en/U.S.-FDA-Approves-BESREMi%C2%AE-ropeginterferon-alfa-2b-njft-as-the-Only-Interferon-for-Adults-With-Polycythemia-Vera.
- FDA approves treatment for rare blood disease. News release. US Food and Drug Administration. Accessed November 15, 2021. https://www.prnewswire.com/news-releases/fda-approves-treatment-for-rare-blood-disease-301423378.html.
- Besremi. Package Insert. PharmaEssentia Corporation; 2021. Accessed November 15, 2021. https://us.pharmaessentia.com/wp-content/uploads/2021/11/BESREMi-USPI-November-2021-1.pdf.