Oral Apixaban Shows Safe, Beneficial Thrombosis Prevention Post-Surgery

July 16, 2020

The first prospective safety trial using oral factor Xa inhibitor in patients undergoing laparotomy shows women preferred and adhered to the drug.

Saketh R. Guntupalli, MD

Oral factor Xa antagonist apixaban (Eliquis) could be a safe alternative for thromboprophylaxis among postoperative women with gynecologic malignant neoplasms.

In findings from a new study conducted by US investigators, apixaban provided safe, more tolerable, and easily-administered preventive care compared to subcutaneous enoxaparin for patients at risk of bleeding events following gynecologic cancer-related surgery.

Investigators, led by Saketh R. Guntupalli, MD, of the University of Colorado School of Medicine at Denver, noted the observed prophylactic benefit of apixaban in this population fills a need for anticoagulation options in women undergoing gynecologic cancer surgery.

Guntupalli and colleagues conducted the multicenter, open-label, blinded, randomized clinical trial in both outpatient and inpatient gynecologic oncology settings. They randomized 400 women undergoing surgery for suspected or confirmed cancer to either oral apixaban or subcutaneous enoxaparin after operation.

The team compared major bleeding and clinically relevant nonmajor bleeding event rates among both treatment arms during a 90-day follow-up period.

As they noted, current clinical guidelines state a 28-day course of enoxaparin is recommended for thromboprophylaxis post-surgery for gynecologic cancer. But patient burdens limit such adherence.

“Current recommendations to decrease the risk of VTE have included subcutaneous enoxaparin for 28 days but they have been met with adherence issues because of pain and bruising at injection site and cost,” investigators wrote. “Given the potential lethality of VTE in this patient population, effective and convenient prophylaxis is critical in reducing this burden.”

Median patient age was 58 years old (range, 18-89 years), with no significant differences in race/ethnicity, cancer stage, or surgery modality (open or robotic) across treatment groups.

Investigators observed no statistically significant differences between the apixaban and enoxaparin treatment arms in regard to major bleeding events; both had just 1 patient suffer an event (OR, 1.04; 95% CI, 0.07-16.76; P >.99). Similar non-significant differences were observed in clinically relevant nonmajor bleeding events (12 vs 19; OR, 1.88; 95% CI, 0.87-4.1; P = .11), and venous thromboembolic events (2 vs 3; OR, 1.57; 95% CI, 0.26-9.50; P = .68) among apixaban and enoxaparin patients, respectively.

Safety outcomes including adverse events, treatment adherence, and quality of life also did not differ significantly between treatment arms.

However, patient satisfaction—as per the ease of taking medication—was reported in a significantly greater rate of apixaban patients (186 [98.6%]) than those on enoxaparin (110 [58.8%]; OR, 0.06; 95% CI, 0.01-0.25; P <.001). Additionally, pain associated with treatment per patient was significantly decreased (2.1% vs 49.2%; OR, 9.20; 95% CI, 2.67-31.82; P <.001).

Guntupalli and colleagues noted that, while the study was underpowered for VTE prevention, rates were slightly decreased among the apixaban arm. Nonetheless, the difference was not significant.

“This finding suggests that this modality is effective in preventing VTE with a greater sample size of high-risk women with gynecologic cancer,” they wrote.

To their knowledge, this is the first prospective trial to observe the safe use of an oral factor Xa inhibitor in patients undergoing laparotomy. As the rate of cancer procedures which require large abdominal incisions in a variety of disease sites increases, such data could be beneficial for surgery in sites that require significant abdominal debulking.

“Surgeons should continue to use appropriate postoperative VTE prophylaxis in high-risk surgical oncology patients to help prevent this potentially life-threatening outcome and may consider at their discretion the safety of thromboprophylaxis options,” they concluded.

The study, “Safety and Efficacy of Apixaban vs Enoxaparin for Preventing Postoperative Venous Thromboembolism in Women Undergoing Surgery for Gynecologic Malignant Neoplasm,” was published online in JAMA Network Open.


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