FDA approves Idelvion for hemophilia B
The FDA approved a novel agent for the treatment of patients with hemophilia B.
Coagulation Factor IX (recombinant), albumin fusion protein (Idelvion, CSL Behring), is indicated for children and adults for routine prophylaxis to prevent or reduce frequency of bleeding episodes. It also is indicated for on-demand use for prevention and control of bleeding episodes, as well as for perioperative bleeding management.
Idelvion, a long-acting albumin fusion protein administered intravenously, links recombinant coagulation Factor IX with recombinant albumin. Appropriate patients aged 12 years and older may go up to 14 days between infusions, according to a CSL Behring-issued press release.
Hemophilia B ― a congenital bleeding disorder in which patients have defective or deficient Factor IX ― is associated with spontaneous or prolonged bleeding, particularly into the joints, muscles or internal organs. The condition occurs primarily in men, with an incidence of approximately one in every 25,000 male births, according to the press release.
“The approval of this long-acting recombinant Factor IX therapy for hemophilia B is vital, as physicians need more options to help their patients effectively and safely manage their bleeding disorder,” Elena Santagostino, MD, PhD, professor in the medical school of clinical and experimental hematology at University of Milan/IRCCS Maggiore Hospital in Italy and lead investigator of the PROLONG-9FP clinical development program, said in the press release. “As the only recombinant Factor IX therapy offering up to 14-day dosing, Idelvion helps patients maintain Factor IX activity levels over a long period of time. This provides them with greater freedom from frequent infusions, which is an important attribute for patients who require a prophylactic regimen but don’t want treatment to disrupt their active lives.”
The FDA based its approval on results of the PROLONG-9FP program, which includes several open-label, multicenter trials designed to assess Idelvion in patients aged 1 to 61 years. All patients had hemophilia B, with Factor IX levels of 2% or less.
Clinical trial results showed Idelvion maintained Factor IX activity levels above 5% ― the threshold established for mild hemophilia ― with both 7-day and 14-day dosing.
Among patients who received on-demand therapy, 94% of bleeds were controlled with one infusion, and 99% of bleeds were controlled with one or two infusions. Researchers reported a median annualized spontaneous bleeding rate of 0.
The most frequently reported adverse reaction among Idelvion-treated patients was headache.
“Idelvion has the potential to significantly impact the treatment of hemophilia B as it maintains Factor IX activity levels above 5% over a prolonged period of time. This provides excellent bleeding control,” said Andrew Cuthbertson, BMedSci, MBBS, PhD, FTSE, FAHMS, chief scientific officer and director of research and development for CSL Limited, said in the press release. “We are proud to add this new therapy to our growing portfolio of bleeding disorder products, and are particularly excited about the positive impact treatment with Idelvion can have on the well-being of patients with hemophilia B.”