Efficacy Study to Evaluate B-Lock™ as an Antimicrobial Lock Solution in Dialysis Patients With a CVC

Hypothesis: B-Lock is a safe and effective catheter lock solution that will maintain catheter patency and reduce Central Line Associated Blood Stream Infections (CLABSI) in dialysis patients using a central venous catheter (CVC) for vascular access. The study is a prospective, randomized, site unblinded/sponsor blinded, clinical study of a minimum of 300 dialysis patients using a central venous catheter (CVC) for vascular access. Patients will be randomized 1:1 to receive either the investigational medical device (B-Lock or IMD) or active control heparin (5000 U/mL) (ACH) and observed for a minimum of 45 days or a maximum of 273 (expected average 160 days). IMD or ACH will be instilled into the catheter lumens (dual lumen catheters) at the end of each dialysis session and removed prior to the initiation of the next dialysis session. The primary objectives of this study are: * To demonstrate the safety of B-Lock in dialysis patients * To demonstrate the non-inferiority or, if proven to be non-inferior, superiority of B-Lock relative to ACH with respect to maintaining catheter patency as defined by the use of recombinant tissue plasminogen activator for maintaining adequate blood flow through the dialysis catheter * To demonstrate the superiority of B-Lock relative to ACH with respect to the incidence of CLABSI