Announcement
Thank you for attending THSNA 2026. The virtual meeting is now closed.
Thank you for attending THSNA 2026. The virtual meeting is now closed.
Presentation Details
| Evaluation of Apixaban Dosing Practices for VTE/PE in Medically Complex Patients Thalia Padilla Kelley1, Rebecca Pontius1, Aamna Khan2, Marie Piatski1, Eric Bleem1, Nancy Padilla-Lazos1, Jake Berkowitz1, Onyekachi Anya3, Robert Nixon1, Kevin Huang1, Corinne Lavasseur1, Joseph Shatzel1. 1Oregon Health & Science University, Portland, OR, USA.2Hillsboro Medical Center, Portland, OR, USA.3 Legacy Salmon Creek Medical Center, Portland, OR, USA |
Abstract
Background: Apixaban is widely used for the treatment and extended management of unprovoked VTE, however, real-world prescribing often deviates from FDA-approved dosing recommendations. Optimal long-term anticoagulation in high-risk populations such as patients with severe obesity, CKD, malignancy, or hematologic disorders remains uncertain. These groups are underrepresented in clinical trials and face competing risks of thrombosis and bleeding, making real-world data essential to guide individualized therapy. Methods: We conducted an institutional review board approved retrospective chart review of 601 adults aged 18–99 years treated with apixaban for VTE or PE within a single quaternary healthcare system. Patients included a broad range of body mass indices and complex comorbidities. Apixaban dosing after the initial treatment phase was categorized as standard dose (5 mg twice daily) for six months than reduced dose (2.5 mg twice daily). Prescribing provider specialty (primary care vs hematology/oncology) was recorded to assess variation in practice. Clinical outcomes included recurrent VTE/PE, major bleeding, clinically relevant non-major bleeding, and all-cause mortality. Time-to-event outcomes were analyzed using Kaplan–Meier methods, and dosing strategies were compared using a prespecified non-inferiority framework. Statistical analyses were performed using R and Prism. Results: Our cohort demographics include a mean age of 61 years and patients with solid tumors (21%), hematologic malignancies (11%), inherited or acquired thrombophilia’s (12%), and a wide range of body mass indices (18–70 kg/m²) (12%). Of 601 patients, only 18% were transitioned to guideline-recommended reduced-dose apixaban after the initial treatment phase, even among high-risk subgroups such as those with thrombophilia, cancer-associated thrombosis, or severe obesity, reflecting clinician concern for recurrent thrombosis. Hematology and oncology specialists were more likely to implement reduced-dose therapy after six months, whereas primary care providers more often continued standard dosing. Rates of recurrent VTE and PE were similar between patients maintained on apixaban 5 mg twice daily and those transitioned to 2.5 mg twice daily (1.5% in both groups). Major bleeding occurred more frequently with full-dose therapy (0.4% vs 0.2%), and clinically relevant non-major bleeding was also higher in the 5 mg twice daily group (7% vs 3%). Higher bleeding rates with long-term full-dose anticoagulation were particularly observed among patients with malignancy, renal insufficiency, or advanced age. Differences in all-cause mortality were primarily attributable to baseline comorbidity burden rather than anticoagulant dose, and no dose-specific safety signals were identified. Conclusions: In this medically complex cohort, reduced-dose apixaban may provide comparable protection against recurrent thrombosis while lowering bleeding risk compared with continued full-dose therapy. Substantial variation in dosing practices across specialties highlights opportunities for more standardized, risk-informed anticoagulation strategies. These real-world findings can help clinicians confidently individualize prophylactic or extended-phase apixaban therapy when clinically appropriate.
No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.
No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.