ASH 2017: Direct Oral Anticoagulant May Reduce Recurrence of VTE in Patients With Cancer
People with cancer have an increased risk of developing blood clots, with roughly one in five experiencing venous thromboembolism (VTE). International guidelines recommend treatment using low–molecular-weight heparin, an anticoagulant that is injected subcutaneously; however, new results from a large pilot trial suggest that direct oral anticoagulants—newer blood thinners administered as a daily pill—could be a safe and beneficial alternative for treating VTE in selected patients. These findings were presented by Young et al at the 59th American Society of Hematology (ASH) Annual Meeting & Exposition (Abstract 625).
Although there are many causes and risk factors for VTE, its increased prevalence in patients with cancer is thought to be related to a combination of factors, such as immobility from remaining in bed, procoagulants produced by the tumor, and chemotherapy. Because VTE can be life-threatening, blood thinners are used to shrink existing clots and prevent others from forming.
select-d Trial
The select-d trial enrolled 406 patients who had cancer and VTE; most (69%) were receiving cancer treatment (typically chemotherapy) at the time of their VTE. Half were randomly assigned to receive low–molecular-weight heparin (dalteparin), and half were assigned to receive a direct oral anticoagulant (rivaroxaban).
After 6 months of treatment, the VTE recurrence rate was 4% among those receiving the direct oral anticoagulant and 11% in those receiving dalteparin.
The results for secondary outcomes were mixed. In patients receiving the direct oral anticoagulant, there were more major bleeding events (11 patients) and a marked increase in clinically relevant nonmajor bleeding events (25 patients) compared with those taking heparin (6 and 6 patients, respectively). The researchers are conducting further analyses to try to understand the factors that may have contributed to this difference.
“Clinicians are already adopting direct oral anticoagulants into practice for these patients,” said lead study author Annie Young, PhD, Professor of Nursing at the University of Warwick, “and now they have data from this study to indicate that direct oral anticoagulants are potentially safe in cancer patients. We need to be looking at different groups of people and different types of bleeds in more detail, so we can choose the best treatment for each patient.”
Disclosure: This study was supported by an unrestricted grant from Bayer AG.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
