SAN DIEGO – according to the Phase 3 ADAM VTE trial.
The rates of major bleeding and clinically relevant nonmajor bleeding in patients who received apixaban were similar to those in patients who received dalteparin. However, the rate of VTE recurrence was significantly lower with apixaban than it was with dalteparin.
“[A]pixaban was associated with very low bleeding rates and venous thrombosis recurrence rates compared to dalteparin,” said Robert D. McBane II, MD, of the Mayo Clinic in Rochester, Minn., at the annual meeting of the American Society of Hematology.
The trial included 300 adults (aged 18 years and older) with active cancer and acute VTE who were randomized to receive apixaban (n = 150) or dalteparin (n = 150). The dose and schedule for oral apixaban was 10 mg twice daily for 7 days followed by 5 mg twice daily for 6 months. Dalteparin was given subcutaneously at 200 IU/kg per day for 1 month followed by 150 IU/kg daily for 6 months. Among the patients in the study, 145 patients in the apixaban arm and 142 in the dalteparin arm ultimately received their assigned treatment.
Every month, patients completed an anticoagulation satisfaction survey and bruise survey (a modification of the Duke Anticoagulation Satisfaction Scale). They also underwent lab testing (complete blood count, liver and renal function testing) and were assessed for outcomes, medication reconciliation, drug compliance, and ECOG status on a monthly basis.
Patient characteristics
Baseline characteristics were similar between the treatment arms. The mean age was 64 years in both arms, and roughly half of patients in both arms were female. Hematologic malignancies were present in 9% of patients in the apixaban arm and 11% in the dalteparin arm. Others included lung, colorectal,
pancreatic/hepatobiliary, gynecologic, breast, genitourinary, upper gastrointestinal, and brain cancers.
Of patients in the study, 65% of those in the apixaban arm and 66% in the dalteparin arm had distant metastasis, and 74% of patients in both arms were receiving chemotherapy while on study.
Patients had the following qualifying thrombotic events:
- Any pulmonary embolism (PE) – 55% of patients in the apixaban arm and 51% in the dalteparin arm
- Any deep vein thrombosis (DVT) – 48% and 47%, respectively
- PE only – 44% and 39%, respectively
- PE with DVT – 12% in both arms
- DVT only – 37% and 35%, respectively
- Lower extremity DVT – 31% and 34%, respectively
- Upper extremity DVT – 17% and 14%, respectively
- Cerebral venous thrombosis (VT) – 1% and 0%, respectively
- Splanchnic VT – 8% and 18%, respectively.
Bleeding, thrombosis, and death
The study’s primary endpoint was major bleeding, which did not occur in any of the apixaban-treated patients. However, major bleeding did occur in two (1.4%) patients in the dalteparin arm (P = .14).