AstraZeneca to proceed with regulatory filings to convert from conditional to full approval in the US and EU.

ANNEXA-I, a post-marketing Phase IV trial to assess the efficacy and safety of Andexxa (andexanet alfa) in patients on oral FXa-inhibitor treatment including apixaban and rivaroxaban experiencing an intracranial haemorrhage, will be stopped early.¹ The decision is based on achieving pre-specified stopping criteria of superior haemostatic efficacy, the ability to limit the expansion of a potentially life-threatening bleed in the brain, versus usual care.^1,2

The recommendation to stop the trial was made by the independent Data and Safety Monitoring Board (DSMB) following a planned interim assessment of efficacy after 450 patients had been randomised and followed for one month, which showed Andexxa’s reversal benefits earlier in the study enrolment than originally anticipated.

Stuart J. Connolly, MD, FRCPC, Senior Scientist at Population Health Research Institute and professor emeritus at McMaster University in Hamilton, Ontario, said: “We are pleased that the study has met its efficacy endpoint at the planned interim analysis, showing improved control of bleeding with targeted anticoagulation reversal, compared to usual care. We look forward to sharing the full efficacy and safety results after further analysis, with the hope that the data will pave the way for further guidance on the treatment of potentially life-threatening bleeds.”

Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said:

“Millions of people worldwide depend on FXa inhibitors to prevent harmful blood clots from forming, but these agents also carry a small but significant risk of increasing the likelihood that an acute major bleed could occur. We are proud to offer the first and only approved treatment to specifically reverse FXa inhibitor activity and help achieve haemostasis, providing an effective and reliable treatment when immediate care is required.” 

Andexxa is specifically designed to rapidly reverse the anticoagulation effects of direct oral FXa inhibitors due to life-threatening or uncontrolled bleeding.³ The treatment has been granted accelerated approval in the US and is conditionally approved in the EU, Switzerland and UK as Ondexxya for adults treated with FXa inhibitors apixaban and rivaroxaban. It is also approved in Japan as Ondexxya for FXa inhibitors apixaban, rivaroxaban, or edoxaban. Use of Andexxa is supported by over 15 national and international guidelines across multiple disciplines.^4-19

AstraZeneca will now initiate closure of ANNEXA-I and proceed with regulatory filings in the US and EU to convert to full label approval. The full efficacy and safety results will be submitted for presentation at a forthcoming medical meeting and publication.

Notes

Life-threatening bleeding

Millions of people worldwide depend on FXa inhibitors to manage their risk of blood clots developing.²⁰ These medicines are important to maintaining health and wellbeing, however, carry a small but significant risk of an acute major bleed.^21-26 There are different forms of uncontrolled bleeding that may occur. One that has high risk of being life threatening, if left untreated, is an intracranial haemorrhage (ICH).^27-29 There is an urgent need for access to specific reversal agents for patients treated with FXa inhibitors as major bleeding can be life threatening and can happen inside the body, so may not be visible. As prescriptions for FXa inhibitors increase, the need for efficacious and reliable care for uncontrolled bleeds grows.^30,31

ANNEXA-I

ANNEXA-I is a randomised, multi-center clinical trial designed to determine the efficacy and safety of andexanet alfa versus usual care in adult patients (≥18 years) with an intracranial haemorrhage who have received oral FXa inhibitors, including apixaban and rivaroxaban, and is part of the post-marketing study commitment required to support full US and EU approvals.¹ ANNEXA-I enrolled over 450 adult patients with an intracranial haemorrhage who were also being treated with Factor Xa (FXa) inhibitors (apixaban and rivaroxaban), a type of direct oral anticoagulant (DOAC), commonly referred to as blood-thinners. The primary endpoint was the rate of effective haemostasis, or stopping the flow of blood, following treatment with Andexxa compared with usual care, including four-factor prothrombin complex concentrate.^1,2 ANNEXA-I was conducted in patients with acute ICH, which are typically assessed by hematoma bleed size and location.¹ There is an established method for measurement of hematoma size and expansion, allowing for definitive assessment of haemostatic efficacy.^32,33  

Andexxa

Andexxa (andexanet alfa)is a recombinant protein specifically designed to bind to FXa inhibitors and rapidly reverse their anticoagulant effect.³⁴ Andexxa is a modified form of the human FXa molecule, an enzyme that helps blood clot. Andexxa works by acting as a decoy for oral and injectable FXa inhibitors, which target and bind to FXa, allowing them to exert their anticoagulant effect. When Andexxa is given through an intravenous infusion to a patient with FXa inhibitor-related bleeding, it binds with high affinity to the FXa inhibitor, prevents it from inhibiting the activity of FXa and reverses the anticoagulant effects of the inhibitor.  

AstraZeneca in CVRM  

Cardiovascular, Renal and Metabolism (CVRM), part of BioPharmaceuticals, forms one of AstraZeneca’s three disease areas and is a key growth driver for the Company. By following the science to understand more clearly the underlying links between the heart, kidneys and pancreas, AstraZeneca is investing in a portfolio of medicines for organ protection and improving outcomes by slowing disease progression, reducing risks and tackling co-morbidities. The Company’s ambition is to modify or halt the natural course of CVRM diseases and potentially regenerate organs and restore function, by continuing to deliver transformative science that improves treatment practices and CV health for millions of patients worldwide. 

AstraZeneca
AstraZeneca (LSE/STO/Nasdaq: AZN) is a global, science-led biopharmaceutical company that focuses on the discovery, development, and commercialisation of prescription medicines in Oncology, Rare Diseases, and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca operates in over 100 countries and its innovative medicines are used by millions of patients worldwide. Please visit astrazeneca.com and follow the Company on Twitter @AstraZeneca.

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