FDA Approves Rebinyn for Routine Prophylaxis to Prevent Bleeding in Patients with Hemophilia B

Officials with the FDA have approved coagulation factor IX (recombinant), GlycoPEGylated (Rebinyn; Novo Nordisk) for routine prophylaxis in adults and children to prevent bleeding in individuals with hemophilia B.¹

Hemophilia B is a rare genetic disorder characterized by insufficient levels of the blood protein factor IX, which is needed for clotting. Mild cases may experience bleeding symptoms only after surgery or injury, whereas bleeding symptoms may occur after a minor surgery or spontaneously in some moderate and most severe cases.²

The disorder occurs in approximately 1 in 25,000 male births and is less prevalent in women. Although many women who carry the gene do not have symptoms, an estimated 10% to 25% will develop mild symptoms, and can potentially develop moderate or severe symptoms.²

Rebinyn, an extended half-life treatment used to replace clotting factor IX (FIX), was approved by the FDA in 2017 for on-demand treatment and control of bleeding episodes, as well as for perioperative management of bleeding in adults and children. The new, expanded indication will allow for prophylactic treatment resulting in high FIX levels and reduced risk of bleeding. According to a press release, this is an important step because prophylaxis can enable individuals with hemophilia to participate in physical and social activities.¹

“This important milestone for Rebinyn allows patients with hemophilia B of all ages to maintain high factor levels until their next weekly dose,” said Melissa Leichter, vice president and commercial lead of rare disease at Novo Nordisk, in the press release.¹

The safety and efficacy of the treatment was investigated in 5 multi-center, non-controlled, open-label trials with on-demand treatment of bleeding episodes, perioperative management of major and minor surgery, and routine prophylaxis or pharmacokinetic evaluation in 115 previously treated patients with hemophilia B. In the studies, a total of 15,167 injections were administered over a median of 733 days, equivalent to 15,137 exposure days and corresponding to 292 patient-years.¹

According to the study results, previously treated adults and adolescents taking Rebinyn 40 IU/kg once weekly for 1 year in the clinical trial program experienced an overall median annualized bleeding rate of 1.04 along with zero observed inhibitors or thrombotic events. Common adverse reactions in this group included itching and injection site reactions.¹

“In clinical studies, when adults and adolescent people living with hemophilia B were given prophylactic treatment with Rebinyn, patients experienced factor IX activity in the same range as people without hemophilia (above 40%) for nearly 80% of the week,” Allison P. Wheeler, MD, MSCI, said in the press release. “This is supported by the World Federation of Hemophilia acknowledgement that replacement therapy with extended half-life FIX allows for more ambitious prophylaxis.”¹

REFERENCES

1. Novo Nordisk receives FDA approval for Rebinyn for routine prophylaxis to prevent bleeding in people living with Hemophilia B. Novo Nordisk; July 29, 2022. Accessed August 1, 2022. https://www.novonordisk-us.com/content/nncorp/us/en_us/media/news-archive/news-details.html?id=127305
2. Hemophilia B. National Organization for Rare Disorders. Accessed August 1, 2022. https://rarediseases.org/rare-diseases/hemophilia-b/#:~:text=Factor%20IX%20is%20a%20clotting,unaffected%20individuals%2C%20they%20bleed%20longer.