Novo Nordisk's Denecimig Shows Tolerable Direct Switch From Emicizumab in Phase 3b FRONTIER5 Hemophilia A Study
核心洞察
Phase 3b FRONTIER5 results published in the Journal of Thrombosis and Haemostasis show denecimig was well tolerated after a direct switch from emicizumab without washout or loading dose.
Among 61 adolescents and adults with hemophilia A (搜索), 107 treatment-emergent adverse events occurred in 43 patients (70.5%), with 98.1% classified as mild to moderate.
Exploratory data showed mean thrombin peak height rose 78.8% from baseline into the normal range and was sustained over 26 weeks with no clinical evidence of excessive clotting.
Novo Nordisk announced that phase 3b results from the FRONTIER5 study of investigational denecimig were published in the Journal of Thrombosis and Haemostasis, showing that a direct switch to the subcutaneous denecimig pen injector from the emicizumab vial and syringe injection system was well tolerated in adolescents and adults living with hemophilia A (搜索), with or without inhibitors. The 26-week data demonstrated that the switch could be made without a washout period or a denecimig loading dose, with no unforeseen safety concerns.
The open-label phase 3b FRONTIER5 safety study enrolled 61 adults and adolescents aged 12 years and older with hemophilia A (搜索), with or without inhibitors, all of whom completed the 26-week treatment period.
Safety Endpoint Results
The primary safety endpoint found 107 treatment-emergent adverse events (TEAEs) between Week 0 and Week 26 of treatment, observed in 43 patients (70.5%). Most of these events, 98.1%, were mild to moderate. Twenty-four TEAEs were possibly or probably related to denecimig. Denecimig safety was consistent with findings previously shared from the FRONTIER research program.
No thromboembolic events, hypersensitivity reactions, or TEAEs leading to discontinuation were observed, and there was no clinical evidence of neutralizing anti-denecimig antibodies.
"Switching to a new hemophilia treatment typically requires careful spacing between treatments to avoid creating a combined, additive effect on thrombin generation," said Allison P. Wheeler, MD, University of Colorado School of Medicine, Aurora CO. "Additionally, that transition period requires close monitoring and coordination to manage gaps in protection that could increase the risk of breakthrough bleeding. Crucially, patients in the FRONTIER5 study were able to safely switch directly to denecimig without waiting until emicizumab is completely cleared from their system, and without needing an initial loading dose to jump-start their new regimen."
Thrombin Generation and Pharmacokinetics
Exploratory results showed that denecimig increased thrombin generation, a measure of blood clotting function, to levels in the normal range after switching from emicizumab. Mean thrombin peak height increased by 78.8% from baseline across all dosing groups, and the increase was sustained over the 26-week study period without any clinical evidence of synergistic thrombin peak height effect or excessive clotting across all dosing frequencies. Denecimig also reached steady-state plasma concentrations by week 16 without a loading dose.
"What stands out from the published phase 3b data is the well-tolerated switch to denecimig along with the sustained increase in thrombin generation into the normal range," said Stephanie Seremetis, Chief Medical Officer and CVP for Rare Disease at Novo. "The positive device handling data and majority preference for our injection pen was equally encouraging, and a testament to Novo's intentional design process with the goal of providing this patient population additional options for administration."
Device Handling and Treatment Burden
A supportive secondary endpoint assessed among 59 of the 61 enrolled patients using the Hemophilia Device Handling and Preference Assessment (HDHPA) showed that most participants (98.3%) rated the denecimig injection pen as "easy" or "very easy" to use. Most patients (94.9%) reported that the pen was easier to use overall than their previous administration method, and 96.6% preferred the denecimig injection pen to the previous administration method. Responses were similar across each dosage frequency.
An additional supportive secondary endpoint studied in 55 of the 61 enrolled patients found that denecimig reduced treatment burden by an average (standard deviation) of 4.7 points (9.0) at week 26, from a baseline total score of 10.5 (10.2), based on the Hemophilia Treatment Experience Measure (Hemo-TEM).
Regulatory Status and Mechanism
A Biologics License Application (BLA) is currently under review with the US Food and Drug Administration for denecimig as routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients with hemophilia A (搜索), with or without inhibitors, in once-weekly, once-every-two-weeks, or once-monthly dosing frequencies.
Denecimig is an investigational bispecific antibody Factor VIIIa (FVIIIa) mimetic designed as routine prophylaxis for adults, adolescents, and children with hemophilia A (搜索) (congenital FVIIIa deficiency), with or without inhibitors. Intended to be administered under the skin in a single-dose, prefilled disposable pen, denecimig bridges Factor IXa and Factor X. This action mimics FVIIIa function, helping restore the body's thrombin generation capacity and enabling blood to clot.
Disease Burden and Study Context
Hemophilia A (搜索) is a rare, inherited bleeding disorder in which a deficiency in clotting factor VIII hinders thrombin production, impairing the body's ability to make blood clots and stop bleeding. According to the World Federation of Hemophilia's Annual Global Survey 2024, hemophilia is estimated to affect approximately 836,000 people worldwide, and hemophilia A is estimated to account for 80-85% of all hemophilia cases. Some people with hemophilia A develop inhibitors, an immune system response to the clotting factors used in replacement therapy, which can cause treatment to become ineffective; it has been estimated that approximately 30% of people living with hemophilia A will develop inhibitors.
The FRONTIER clinical program includes FRONTIER1-5 and investigates denecimig as a prophylactic treatment for adults, adolescents, and children with hemophilia A (搜索), with or without inhibitors. FRONTIER5 specifically investigated the safety of switching from emicizumab, an existing hemophilia A treatment, to denecimig without a washout period or loading dose in adolescents and adults aged 12 and older. The open-label design and 26-week observation period limit conclusions about longer-term outcomes, and the laboratory thrombin generation results do not, on their own, establish comparative effectiveness in preventing bleeding.