PhD Scientific Days 2025

Health Sciences I.

Assessment of the correlation between apixaban plasma concentration and its clinical efficacy

Előadó neve

Stubnya János Domonkos

Neptun code

Z2T3YH

Előadó munkahelye

Semmelweis University, Department of Intensive Therapy

Előadó telefonszáma

+36205638010

Előadó e-mail címe

stubnyajanos2000@gmail.com

Az előadás címe

Assessment of the correlation between apixaban plasma concentration and its clinical efficacy

Szerző(k) neve és munkahelye

János Domonkos Stubnya¹, Hanna Szász², Anna Párkányi¹, Máté Berczi¹, Dalma Skultéti¹, Adrienne Fehér³, Gellért Karvaly³, András Kállai¹, János Fazakas¹

1: Semmelweis University, Department of Intensive Therapy
2: Semmelweis University, Faculty of Medicine
3: Semmelweis University, Department of Laboratory Medicine

Bemutatás módja

Szóbeli

Szekció

Health Sciences I.

Language of the presentation

Hungarian

Preferred session

Health Sciences

Összefoglaló szövege

Introduction: Apixaban (AP) exerts its anticoagulant effect through direct, reversible inhibition of activated factor X (FXa). While several methods are available to determine serum drug levels, the relationship between concentration and clinical effect remains uncertain.
Aims: To compare serum AP concentrations measured by mass spectrometry (MS) and chromogenic anti-FXa assays (Chr), and to assess the corresponding anticoagulant effects at the measured drug levels using viscoelastic testing (VET).
Methods: The study included patients who had previously received VET-guided thrombolysis for pulmonary embolism (PE) at the Central ICU of Semmelweis University between April 2022 and September 2023, and were treated with apixaban (2×5 mg/day) during follow-up. At 1-, 3-, and 12-month control visits, MS and Chr drug level measurements were performed, along with ClotPro® VETs (EX, IN, and RVV tests), both before and 2 hours after AP administration. Data were analyzed using GraphPad Prism software (Spearman correlation, Wilcoxon test, linear regression, Bland-Altman analysis).
Results: A total of 22 patients were enrolled, yielding 110 individual measurements in total. MS yielded significantly higher apixaban concentrations than Chr (median: 149 vs. 128 ng/mL, p < 0.0001), as confirmed by Bland-Altman analysis. MS levels showed a moderate and significant correlation with CT values in EX (r=0.6565) and IN (r=0.6331), and a strong correlation in RVV (r=0.7616). However, linear regression revealed only modest coefficients of determination (R²: EX=0.44; IN=0.3028; RVV=0.5219), suggesting non-linear relationships. Comparison of trough and peak AP levels revealed statistically significant CT prolongation across all three tests (p<0.0001 for EX, RVV and IN), though all CT values in the IN test remained within the normal range regardless of drug level.
Conclusions: MS provided consistently higher AP plasma levels than Chr. While RVV tests showed the strongest correlation between drug level and anticoagulant effect, the low R² values imply that one cannot reliably infer one from the other. The modest CT prolongation in IN assays raises the possibility that 2×5 mg apixaban may yield only prophylactic-level anticoagulation. Our results highlight the importance of functional monitoring in guiding personalized anticoagulant therapy.
Funding: 2024-2.1.1-EKÖP-2024-00004

University

Semmelweis University

Supervisor

TDK Supervisor: András Kállai, MD, Ph.D.; MD-Ph.D. Supervisor: János Fazakas, MD, Ph.D.

Publication of my abstract

I give consent to the publication of my abstract on the website of the congress.

phd.section.field

in doctoral studies before complex exam (PhD)

Kind

Szabad

Status

elfogadva

Accepted presentation method

szóbeli

Előadás fájl jóváhagyás

nem hagyta jóvá

Előadó

8126

Start

15:45

End

16:00