This randomized, single-center, PROBE trial evaluates whether adding low-dose apixaban (2.5 mg orally every 12 hours) to standard intraluminal heparin lock prolongs primary functional patency of tunneled hemodialysis catheters compared with standard heparin lock alone. Adult patients on hemodialysis with a recently implanted, functioning tunneled catheter (≥8 days) will be randomized 1:1 and followed up to 24 months (or until catheter loss). Primary outcome is time to first intervention for catheter dysfunction or definitive catheter loss. Secondary outcomes include primary-assisted and secondary patency, thrombotic dysfunction, rescue procedures, catheter-related infection, bleeding (ISTH), and mortality. Outcomes adjudication will be blinded.
Age ≥18 years with end-stage kidney disease (CKD stage 5) receiving maintenance hemodialysis or initiating hemodialysis.
Recently placed tunneled, double-lumen central venous hemodialysis catheter (tunneled CVC) in place for ≥8 days, with a post-placement radiograph confirming adequate tip position.
Permitted catheter insertion sites: right internal jugular, left internal jugular, right femoral, or left femoral vein.
Adequate initial catheter function, defined as ability to achieve the prescribed extracorporeal blood flow (suggested ≥300 mL/min) for ≥8 days after catheter placement.
Non-tunneled hemodialysis catheter, subclavian catheter, or intracaval catheter placement not consistent with the protocol (e.g., catheter located in the SVC/IVC without a subcutaneous tunnel, or catheter location/site not permitted by the study).
Tunneled catheter placed <8 days before randomization or radiographically confirmed catheter tip malposition at screening.
Active bleeding; active peptic ulcer disease; or clinically significant gastrointestinal bleeding within the past 30 days; uncorrectable INR >1.5; platelet count <100,000/µL.
High bleeding risk (HAS-BLED score >3) or major bleeding that is active or recent.