Acute coronary syndrome during active infusion of andexanet alfa.

Now withdrawn from the US market, andexanet alfa was initially approved by the FDA in 2018 to reverse life-threatening bleeds associated with factor Xa (FXa) inhibitors, specifically apixaban and rivaroxaban. Observed effects of andexanet alfa include a reduction in anti-FXa activity resulting in hemostatic efficacy. However, thrombotic events including myocardial infarction and deep venous thrombosis, typically occurring 6 to 30 days after infusion, have also been observed. This case presents the first known patient to develop an ST-segment elevation myocardial infarction while actively receiving infusion of andexanet alfa, which was an approved therapy at the time of the patient's treatment.