Norwegian Medicines Agency (health authority of Norway) published a drug safety alert of drug ineffectiveness for heparin due to interaction with andexane alpha. To foster awareness, this significant safety information is disseminated to health care professionals for early implementation of risk minimizing measures.

Andexanet alpha is a recombinant modified factor Xa protein for the reversal of anticoagulation effect caused by apixaban and rivaroxaban in patients with uncontrolled bleeding which is life-threatening. In May 2018, FDA approved this reversal agent for factor Xa inhibitors as an orphan drug based on the results of two phase 3 trials, ANNEXA-A and ANNEXA-R. These trials evaluated the efficacy and safety of andexanet alpha in the reversing of apixaban and rivaroxaban, respectively, in healthy volunteers.

Heparin is an anti-coagulant which is used in the treatment and prevention of blood clots (blood thinning agent).

Some recent Studies demonstrated that the prior use of andexanet alpha before initiating treatment with heparin has resulted lack of blood thinning effect for heparin (drug ineffectiveness).

Important information for health care professionals:

• Andexane alpha neutralizes the blood-thinning effect of heparin by binding to the heparin‑antithrombin III (ATIII) complex.
• Be aware of potential lack of heparin drug efficacy due to andexane alpha (administer Andexane alpha only if it is necessary and consider using IV direct thrombin inhibitors in such situations.
• Be informed that extent and duration of this drug interaction has not evaluated yet, and results from coagulation tests may be misleading if both the drugs are given within a short period of time.
• Liaise with a hematologists for guidance.

Voluntary ADR reporting

All health care professionals and consumers are encouraged to observe for safety outcomes of medicinal products to accumulate safety evidence which could facilitate health authorities to take early regulatory actions for a better patient safety and public health. If you experience any adverse reaction or event which is suspected to the use of any medicinal product, report the same to directly to Norwegian Medicines Agency via online voluntary ADR reporting page.