Thromboprophylaxis with oral apixaban was similar to subcutaneous enoxaparin with regard to safety outcomes in women undergoing surgery for suspected gynecologic malignancies. The oral medication may provide an option that would increase compliance and satisfaction in this setting.
Almost 100,000 women in the United States undergo surgical evaluation for suspected gynecologic malignancies each year, said Saketh Guntupalli, MD, of the University of Colorado School of Medicine in Denver, at the Society of Gynecologic Oncology (SGO) Annual Meeting in National Harbor, Maryland. As the extent of surgical debulking increases, though, so does the risk of bleeding, venous thromboembolism (VTE), and nosocomial infection. VTE after these surgeries occurs in many women, deep vein thrombosis in 26% and pulmonary embolism in 9%, when no prophylaxis is used.
Enoxaparin is currently recommended for thromboprophylaxis, but the subcutaneous agent often leads to compliance issues. Guntupalli presented results of a prospective, randomized, open-blinded trial comparing oral apixaban to subcutaneous enoxaparin; these results were the planned safety interim analysis including 120 patients undergoing surgical evaluation for gynecologic cancer.
Of the 60 patients in each group, 58 (97%) in each completed the 28 days of therapy. The most common cancer sites included uterine, ovarian, and cervical, and patients had a median age of 56.4 years.
There were no major bleeding events in either group, and no VTE events in either arm. Four patients—two in each group—were evaluated for suspected VTE, but ultrasonography or CT angiography yielded negative results in all four.
There were no grade 4 or 5 adverse events in the trial, and Guntupalli said the adverse-event profiles were similar between the two groups. Arthralgia occurred in 7% of apixaban and in 3% of enoxaparin patients (P = .4), and no other adverse event exceeded 5% in frequency and there were no significant differences between the groups.
Patients receiving apixaban reported significantly less pain than those receiving enoxaparin, with an odds ratio of 0.01 (95% CI, 0.0–0.1; P < .001). They also reported less difficulty with taking the medication, with an OR of 75.9 (95% CI, 4.5–1292.4; P = .003).
“Safety analysis suggests apixaban is potentially as safe as standard therapy for post-operative VTE prophylaxis with a similar risk profile,” Guntupalli concluded, adding that the increased patient satisfaction suggests this could be a reasonable treatment option. The efficacy portion of this study is ongoing, with a planned enrollment of 400 patients; 158 have completed the study so far, with no major bleeding events and one VTE (pulmonary embolism) reported in the apixaban arm, related to a deviation in treatment protocol.