Outcomes with anticoagulant therapy for venous thromboembolism (VTE) appear to vary by primary cancer site in patients with cancer occurring in different sites of the body in a recent study published in the journal Thrombosis and Haemostasis.1
Patients with cancer show an increased risk of VTE. When treated for VTE, patients with cancer also show increased rates of recurrence and major bleeding, complicating treatment with anticoagulants. In this study, researchers sought to compare the efficacy and safety of 6 months of treatment with oral apixaban or subcutaneous dalteparin.
The prospective, multinational, open-label Caravaggio study included patients with active cancer who had a symptomatic or incidental acute proximal deep vein thrombosis (DVT) or pulmonary embolism (PE). Patients were randomly assigned to treatment with either oral apixaban or subcutaneous dalteparin for 6 months. Occurrence of objectively confirmed recurrent proximal DVT or PE was the primary outcome of this noninferiority study.
The study had a modified intention-to-treat population consisting of 1155 patients. Primary cancers were gastrointestinal in 32.5% of patients, lung in 17.3%, breast in 13.4%, genitourinary in 12%, gynecologic in 10.3%, hematologic in 7.4%, and in 80 other locations in 6.9% of patients.
Patients receiving apixaban experienced VTE recurrence at a rate of 5.6%, compared with 7.9% in those treated with dalteparin (hazard ratio [HR], 0.64; 95% CI, 0.38-1.08). VTE recurrence rates varied across cancer types. The highest rates of VTE recurrence were seen with gynecologic (10.9%) and gastrointestinal (8.8%) cancers.
Apixaban was favored in terms of VTE recurrence with some cancer types. Absolute risk differences favoring apixaban were 11.9% for patients with gynecologic cancers, 5.5% for those with lung cancer, 3.7% for patients with genitourinary cancer, and 0.6% for those with gastrointestinal cancer.
Rates of major bleeding also varied across cancer types, such as 7.2% of patients with genitourinary cancer compared with 4.8% of patients with gastrointestinal cancer or lower rates for other cancer types. The researchers noted that differences in major bleeding rates across cancer types may have related to specific cancer treatments, in addition to biological heterogeneity or other medications. Apixaban and dalteparin were associated with similar rates of major bleeding across the study population (3.8% vs 4%, respectively; HR, 0.84; 95% CI, 0.41-1.71).
“Oral apixaban is a valid and more patient-friendly alternative to dalteparin for the treatment of a large spectrum of patients with cancer-associated VTE,” the researchers stated. “For these reasons apixaban should be considered for the treatment of the large majority of patients with cancer-associated VTE,” they continued. However, they also noted more research is needed regarding certain cancer types and cancer-associated thrombosis in general.
Disclosures: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Agnelli G, Muñoz A, Franco L, et al. Apixaban and dalteparin for the treatment of venous thromboembolism in patients with different sites of cancer. Thromb Haemost. Published online September 16, 2021. doi:10.1055/s-0041-1735194