AstraZeneca has pulled its anticoagulant therapy, Andexxa (recombinant coagulation factor Xa), from the US market after patient fatalities.
This follows rising concern from the US Food and Drug Administration (FDA) around Andexxa’s benefit-risk profile, as post-marketing studies have revealed that the coagulant can put patients at risk of serious or fatal thromboembolic events.
During the confirmatory Phase III ANNEXA-I study (NCT03661528), which was conducted after Andexxa was granted accelerated approval, thrombosis incidence in the treatment group was 14.6% versus 6.9% in the usual care control arm. There were also six deaths linked to thrombotic events after 30 days in the Andexxa arm, while two patients died in the control cohort.
Following a meeting between members of the FDA’s Cellular, Tissue and Gene Therapies Advisory Committee to discuss these results, the agency left Andexxa’s US market future in limbo back in December 2024, as it refused to fully approve the drug. AstraZeneca has now voluntarily withdrawn Andexxa’s biologics license application (BLA) and will no longer sell or manufacture Andexxa in the US after 22 December 2025.
AstraZeneca originally obtained the rights to Andexxa after its $39bn acquisition of Alexion Pharmaceuticals in 2021. Alexion has previously acquired the drug’s original developer, Portola Pharmaceuticals, in a $1.4bn buyout in 2020.
The coagulant was previously approved on an accelerated basis for the reversal of life-threatening or uncontrolled bleeding triggered by anticoagulants Eliquis (apixaban) and Xarelto (rivaroxaban) back in 2018. When it was on the US market, a boxed warning for thromboembolic events was required.
Currently, Andexxa is still approved for use by the European Medicines Agency (EMA) and the UK’s Medicines and Healthcare Regulatory Agency (MHRA) on a conditional basis.
While it is currently unknown what stance other global regulators will take on Andexxa’s benefit-risk profile, the unfavourable post-marketing safety data could see the therapy fail to gain full approval.
Andexxa pulled in $219m in sales globally in 2024, with $81m of this profit coming from the US.
