Use of Andexanet Associated with Reduced Hematoma Volume Expansion, Increased Occurrence of Thrombotic Events

According to results of a study published in The New England Journal of Medicine, people with intracerebral hemorrhage (ICH) treated with factor Xa (FXa) inhibitors who received andexanet showed reduced hematoma volume expansion compared with those who did not receive andexanet. The medication andexanet is used to reverse the increased risk of hemorrhage associated with FXa treatment for thrombotic events. While hemostatic efficacy was greater in the adexnanet group, use of the medication also was associated with increased incidence of thrombotic events.

The study included a population of 530 people who used FXa inhibitors to treat their acute ICH within the past 15 hours. Participants were randomly assigned 1:1 to receive either andexanet (n=263) or usual care (n=267). At 12 hours past baseline, researchers assessed whether participants achieved hemostatic efficacy, defined as:

• Expansion of hematoma volume by ≤35%
• Increase of ≤7% on the National Institutes of Health (NIH) Stroke Scale
• No receipt of rescue therapy

In terms of results:

• There was greater achievement of hemostatic efficacy for the andexanet group (67.0%) compared with the usual care group (53.1%) (adjusted difference, 13.4 percentage points; 95% CI, 4.6 to 22.2; P=.003).
• The expansion of hematoma volume criterion was found to be the primary driver of the difference in hemostatic efficacy, achieved in 76.7% of participants treated with andexanet and 64.6% of participants who received usual care.
• Of all 271 participants who achieved hemostatic efficacy, most showed ≤20% expansion of hematoma volume.
• Thrombotic events occurred more commonly in the andexanet group (10.3%), compared with the usual care group (5.6%) (difference, 4.6 percentage points; 95% CI, 0.1 to 9.2; P=.048).
  • Seventeen participants in the andexanet group (6.5%) and 4 participants in the usual care group experienced ischemic stroke.

Additionally, more participants in the andexanet group (90%) had arterial fibrillation at baseline, compared with the the usual care group (84%), revealing an area for further investigation.