Andexanet alfa versus non-specific treatments for intracerebral hemorrhage in patients taking factor Xa inhibitors - Individual patient data analysis of ANNEXA-4 and TICH-NOAC

BACKGROUND

Data comparing the specific reversal agent andexanet alfa with non-specific treatments in patients with non-traumatic intracerebral hemorrhage (ICH) associated with factor-Xa inhibitor (FXaI) use are scarce.

AIM

The study aimed to determine the association between the use of andexanet alfa compared with non-specific treatments with the rate of hematoma expansion and thromboembolic complications in patients with FXaI-associated ICH.

METHODS

We performed an individual patient data analysis combining two independent, prospective studies: ANNEXA-4 (180 patients receiving andexanet alfa, NCT02329327) and TICH-NOAC (63 patients receiving tranexamic acid or placebo ± prothrombin complex concentrate, NCT02866838). The primary efficacy outcome was hematoma expansion on follow-up imaging. The primary safety outcome was any thromboembolic complication (ischemic stroke, myocardial infarction, pulmonary embolism, or deep vein thrombosis) at 30 days. We used binary logistic regression models adjusted for baseline hematoma volume, age, calibrated anti-Xa activity, times from last intake of FXaI, and symptom onset to treatment, respectively.

RESULTS

Among 243 participants included, the median age was 80 (IQR 75-84) years, baseline hematoma volume was 9.1 (IQR 3.4-21) mL and anti-Xa activity 118 (IQR 78-222) ng/mL. Times from last FXaI intake and symptom onset to treatment were 11 (IQR 7-16) and 4.7 (IQR 3.0-7.6) h, respectively. Overall, 50 patients (22%) experienced hematoma expansion (ANNEXA-4: n=24 (14%); TICH-NOAC: n=26 (41%)). After adjusting for pre-specified confounders (baseline hematoma volume, age, calibrated anti-Xa activity, times from last intake of FXaI, and symptom onset to treatment, respectively), treatment with andexanet alfa was independently associated with decreased odds for hematoma expansion (aOR 0.33, 95% CI 0.13-0.80, p = 0.015). Overall, 26 patients (11%) had any thromboembolic complication within 30 days (ANNEXA-4: n=20 (11%); TICH-NOAC: n=6 (10%)). There was no association between any thromboembolic complication and treatment with andexanet alfa (aOR 0.70, 95% CI 0.16-3.12, p = 0.641).

CONCLUSION

The use of andexanet alfa compared to any other non-specific treatment strategy was associated with decreased odds for hematoma expansion, without increased odds for thromboembolic complications.

Increased Incidence of Bleeding and Wound Complications With Factor-Xa Inhibitors After Total Joint Arthroplasty

BACKGROUND

Factor-Xa inhibitors have been introduced for prevention of venous thromboembolism (VTE) after joint arthroplasty. However, these agents could also be associated with bleeding or wound complications after surgery.

METHODS

We retrospectively reviewed a consecutive series of 59 patients (31 knees, 28 hips) undergoing joint arthroplasty at a high-volume joint arthroplasty referral center, both before and after implementation of a new VTE risk-stratification tool at our institution. Patients with a history of VTE, bilateral procedures, or medical conditions already requiring VTE chemoprophylaxis were excluded. We reviewed the medical records to determine (1) type of VTE prophylaxis used, (2) incidence of bleeding/wound complications in the postoperative period, (3) incidence of VTE in the postoperative period, and (4) change in serum hemoglobin.

RESULTS

Twenty-seven patients (46%) were given aspirin for VTE prophylaxis, while 32 patients (54%) received a factor-Xa inhibitor. There were no new VTE complications in either group. And 6 of 32 patients (18.7%) in the Xa inhibitor group had a postoperative bleeding/wound complication (4 delayed healing/blistering, 1 hematoma/excessive ecchymosis, and 1 readmission for cellulitis). There were no (0%) bleeding/wound complications in the aspirin group (P = .03). The change in hemoglobin level was -2.76 g/dL in patients receiving aspirin vs -2.84 g/dL in patients receiving a Xa inhibitor (P = .73).

CONCLUSION

In our study of total joint patients, factor-Xa inhibitors were associated with a higher incidence of bleeding/wound complications. The choice of VTE prophylaxis should be based on the perceived risks of bleeding and wound complications compared to the risks of VTE in each patient.