Comparing the proportions of patients that meet criteria for extended prophylaxis with betrixaban based on APEX Trial and FDA Indication
Kaatz S, Conlon A, McLaughlin E, Flanders S, Chopra V, and Paje D. Comparing the proportions of patients that meet criteria for extended prophylaxis with betrixaban based on APEX Trial and FDA Indication. Res Pract Thromb Haemost 2018; 2:217-218
Research and Practice in Thrombosis and Haemostasis
Background: Betrixaban is the first anticoagulant approved in the United States for extended venous thromboembolism (VTE) prophylaxis in hospitalized medical patients. The evidence of benefit was based on data from the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, which used a study population enriched with patients at high risk for VTE, such as those with elevated D-dimer or ≥75 years. However, the Food and Drug Administration (FDA) approved indication covers a broader population with less defined risk. Aims: Compare the proportion of real-world hospitalized medical patients eligible for betrixaban using APEX trial criteria with those using FDA-approved indication. Methods: Trained abstractors collected data from a representative sample of medical patients discharged between January 2012 and November 2017 (prior to betrixaban approval) at 57 hospitals participating in the Michigan Hospital Medicine Safety consortium. Adult, non-pregnant patients without an initial intensive care unit (ICU) stay or surgery were included in this analysis. Applicable elements of APEX trial eligibility and FDA-approved indication were mapped to consortium data. Results: Of 107,803 patients in our multi-center cohort of hospitalized medical patients 1499 (1.4%) would be eligible for betrixaban based on APEX selection criteria and 32,012 (29.7%) based on FDA-approved indication, P<0.001 The proportions of patients meeting each select element of APEX criteria and FDA indication are shown in the Table. Conclusions: Over a quarter of hospitalized medical patients would be considered for betrixaban extended prophylaxis per FDA approval yet a minority would meet APEX final protocol criteria. Marked differences were seen with age, medical conditions and immobility status. Further risk stratification may be necessary to identify patients that would benefit most from betrixaban. Our analysis is limited by absence of data on D-dimer results.