Pivotal data demonstrate once-weekly efanesoctocog alfa provides superior bleed protection

Pivotal data demonstrateonce-weekly efanesoctocog alfa provides superior bleed protection compared to prior factor prophylaxis


  • Investigational once-weekly efanesoctocog alfa prophylaxis met the primary efficacy endpoint providing clinically meaningful bleed protection for people with severe hemophilia A

  • Results underscore the ability of efanesoctocog alfa to sustain normal to near-normal factor levels and the potential to transform prophylactic treatment, providing people with hemophilia A with higher protection for longer

  • Additional data showed efanesoctocog alfa prophylaxis resulted in statistically significant and clinically meaningful improvements in physical health, pain intensity and joint health in patients on prior factor VIII prophylaxis

Paris and Stockholm – July 10, 2022 – Sanofi and Swedish Orphan Biovitrum AB (publ) (Sobi®) (STO:SOBI) presented for the first time today, in a late-breaking session at the 30th International Society on Thrombosis and Haemostasis (ISTH) Congress, positive results from the XTEND-1 pivotal Phase 3 study evaluating the safety, efficacy and pharmacokinetics of efanesoctocog alfa (BIVV001), an investigational factor VIII replacement therapy, in previously treated adults and adolescents ≥12 years with severe hemophilia A.

The study met the primary efficacy endpoint, with once-weekly efanesoctocog alfa prophylaxis providing clinically meaningful bleed protection for people with severe hemophilia A. The median and mean annualized bleeding rates (ABR) were 0.00 (IQR: 0.00-1.04) and 0.71 (SD: 1.43) respectively. The study also met the key secondary endpoint, demonstrating superior bleed protection (p<0.0001) over prior factor VIII prophylaxis with an estimated ABR reduction of 77% and a mean ABR of 0.69 compared to 2.96 on prior prophylaxis, based on an intra-patient comparison (n=78). In a subset of participants (n=17) studied at baseline and week 26, mean factor VIII levels remained in the normal to near-normal range (>40 IU/dL) for the majority of the week, and at 15 IU/dL at Day seven post-dose, providing increased factor activity level protection for patients with once-weekly prophylaxis.

Annette von Drygalski, MD, PharmD

Investigator, Professor and Director, Hemophilia and Thrombosis Treatment Center, UC San Diego

“The phase 3 data demonstrate once-weekly efanesoctocog alfa’s potential to provide superior bleed protection, leading to substantial improvements in physical health, pain and joint health, by sustaining high factor levels for the majority of the week. These unprecedented results may offer people with hemophilia A the possibility to redefine their treatment expectations.”

Data show adults and adolescents treated with once-weekly efanesoctocog alfa experienced statistically significant and clinically meaningful improvements in physical health (p=0.0001), pain intensity (p=0.0276), and joint health (p=0.0101) when comparing week 52 and baseline measurements.i Moreover, efanesoctocog alfa was effective at treating bleeds, including in target joints; 96.7% of bleeds were resolved with a single 50 IU/kg dose. Efanesoctocog alfa was well tolerated and inhibitor development to factor VIII was not detected. The most common treatment-emergent adverse events (>5% of participants overall) were headache, arthralgia, fall, and back pain.

Dietmar Berger, MD, PhD

Global Head of Development and Chief Medical Officer, Sanofi

“We are committed to advancing innovative medicines that disrupt the status-quo and address the unmet needs that persist for people with rare conditions like hemophilia. These robust data illustrate the promise of efanesoctocog alfa’s efficacy with once-weekly dosing and underscore its potential as a therapy with best-in-disease efficacy.”

Anders Ullman, MD, PhD

Head of R&D and Chief Medical Officer, Sobi

“We believe transforming the treatment paradigm for hemophilia A can only be achieved through elevating standards of care towards normal hemostasis. These data demonstrate the profile of efanesoctocog alfa in significant clinical terms, and further strengthen its potential to ultimately improve the lives of many living with this condition.”

The U.S Food and Drug Administration (FDA) granted efanesoctocog alfa Breakthrough Therapy Designation in May 2022, Fast Track designation in February 2021 and Orphan Drug designation in August 2017. The European Commission also granted efanesoctocog alfa Orphan Drug designation in June 2019. Regulatory submission of the Biologics License Application to the U.S. FDA occurred in June 2022 and submission in the EU will follow availability of data from the ongoing XTEND-Kids pediatric study, expected in 2023.




11 views