Andexanet alfa (trade name EU: Ondexxya, U.S.: Andexxa) has been approved in Germany since April 2019 for stopping life-threatening or uncontrolled bleeding in adults who are taking the anti-clotting medications apixaban or rivaroxaban.

Anti-clotting medications (blood thinners) are used by people who have a higher risk of thrombosis or thromboembolism. The anti-clotting medications that can be taken in tablet form include medicines called direct oral anticoagulants (DOACs), such as apixaban and rivaroxaban. Apixaban and rivaroxaban work by inhibiting the clotting factor Xa. They are mainly used to treat atrial fibrillation, after the implantation of an artificial heart valve, an artificial knee joint or an artificial hip, or following pulmonary embolism. Their most common side effects include bleeding in various organs. Severe or life-threatening bleeding is very rare, though.

Andexanet alfa is an antidote to apixaban or rivaroxaban, meaning that it stops or counteracts their effects. If major bleeding occurs, andexanet alfa is supposed to stop the anti-clotting effect produced by the drug that inhibits clotting factor Xa (apixaban or rivaroxaban).


Andexanet alfa is given as a brief intravenous drip (infusion): One milliliter of infusion solution contains 10 mg of andexanet alfa.

Two infusions need to be given in a row. The time between infusions and how long they last mostly depend on when apixaban or rivaroxaban was last used.

Other treatments

The standard treatments for life-threatening or uncontrolled bleeding in people who have used apixaban or rivaroxaban include things like blood products, prothrombin complex concentrates or giving enough fluids.


In 2019, the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) wanted to find out whether andexanet alfa has any advantages or disadvantages compared with the current standard treatments for major bleeding in patients who have used apixaban or rivaroxaban.

But the manufacturer didn’t provide any suitable data with which to do the assessment.

More information

This information summarizes the main results of a review produced by the Institute for Quality and Efficiency in Health Care (IQWiG, Germany). The review was commissioned by the German Federal Joint Committee (G-BA) as part of the “early benefit assessment of medications.” On the basis of the review and the hearings received, G-BA passed a resolution on the added benefit of andexanet alfa (Ondexxya, Andexxa).