Novo Nordisk reported the publication of Phase III data for investigational bispecific antibody denecimig in hemophilia A, showing the therapy cut annualized bleeding rates by up to 99% versus on-demand treatment. The results were published in the New England Journal of Medicine.
The FRONTIER2 study is a Phase III, open-label, randomized controlled trial that enrolled 254 adults and adolescents aged 12 years and older with hemophilia A, with or without factor VIII inhibitors, comparing once-monthly or once-weekly subcutaneous denecimig against prior clotting factor prophylaxis or on-demand treatment over 26 weeks.
Across both dosing arms, the annualized bleeding rate reduction was substantial. Participants receiving once-monthly denecimig experienced approximately 43% fewer treated bleeds compared with their prior preventive clotting factor therapy, and nearly 99% fewer compared with on-demand treatment. Once-weekly dosing produced roughly 54% fewer bleeds versus prior prophylaxis and approximately 96% fewer versus on-demand. Between 64% and 95% of participants in the four denecimig arms reported zero treated bleeds during the main phase, compared with 0% to 37% in comparator arms — with the on-demand arm recording no zero-bleed participants at all. Denecimig was reported as generally well-tolerated; no thromboembolic events and no clinical evidence of neutralizing anti-drug antibodies were observed. Injection-site reactions occurred in 10% of participants, representing 2.6% of injections.
Denecimig is a bispecific antibody that bridges coagulation factors IXa and X, functionally replacing the cofactor activity of the missing or deficient factor VIIIa. This mechanism places it in the same conceptual class as emicizumab (Hemlibra), the Genentech/Roche bispecific antibody that has been the dominant non-factor prophylactic standard since its FDA approval for inhibitor patients in 2017 and expansion to non-inhibitor patients in 2018. Novo positions denecimig as a next-generation molecule engineered for higher binding affinity, potentially supporting less frequent dosing. Cross-trial comparisons are limited by differences in study populations, endpoints, and follow-up duration, and no head-to-head data against emicizumab have been reported.
The FRONTIER2 population reflected the severity distribution typical of hemophilia A clinical programs: 84% of the 254 participants had severe disease, 12% carried FVIII inhibitors, and 26% were adolescents. Four participants (2%) were female. Of the 254 enrolled, 246 completed the 26-week main phase.