Efficacy and Safety of CUSA-081 in the Restoration of Dysfunctional Central Venous Access Device (CVAD) Functionality

Inclusion Criteria: 1. Inability to have 3 mL of blood withdrawn from the selected study catheter; 2. A single or multi-lumen CVAD, implanted ports or peripherally inserted central catheters (PICCs) in place for \> 24 hours and documented as previously being patent and functional; 3. Ability to designate one dysfunctional lumen of a multi-lumen catheter to be used throughout the study for both study drug instillation and assessment of CVAD function; 4. Male and non-pregnant female subjects at least 18 years or older (see note below); 5. Able to have fluids infused at the volume necessary to instill study drug into the CVAD (i.e., up to 2 mL); 6. Informed consent form (ICF) signed and dated indicating that the subject has been informed of and agreed with all pertinent aspects of the study and is willing to comply with all study requirements and procedures. NOTE: A urine pregnancy test is required for all females of childbearing potential. Women in natural post-menopause or permanently sterile do not need to be tested for pregnancy. Natural menopause is defined as the permanent cessation of menstrual periods, determined retrospectively after a woman has experienced 12 consecutive months of lack of menstruation (amenorrhea) without any other obvious pathological or physiological cause. Permanent sterilisation methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. Exclusion Criteria: 1. CVAD (any type) used for Hemodialysis; 2. CVAD known to be dysfunctional for more than 48 hours; 3. Reasonable evidence of mechanical or non-thrombotic occlusion in the selected study catheter (e.g., catheter malposition or migration, sutures, kinks, or precipitates causing obstruction), radiographic assessment is not required; 4. Known or suspected catheter-related bloodstream infection (CRBSI); 5. Use of any intravenously administered fibrinolytic agent or anticoagulant (e.g., alteplase, tenecteplase, reteplase, urokinase or heparin) within 24 hours prior to the treatment period (first instillation of study drug). Use of subcutaneous low molecular weight heparin (LMWH), unfractionated heparin (UFH) or heparinoids for prophylaxis of thromboembolic events is allowed. Furthermore, the use of oral anticoagulants is allowed. 6. Known to be at high risk for bleeding events or embolic complications in the opinion of the Investigator, or has a known condition for which bleeding constitutes a significant hazard (e.g. recent stroke, recent intracranial or intraspinal surgery or serious head trauma, intracranial neoplasm, arteriovenous malformation or aneurysm, known bleeding diathesis); 7. Uncontrolled hypertension (systolic BP ≥160 or diastolic BP ≥110 mmHg) at screening; 8. Clinically unstable in the opinion of the site investigator; 9. Known to be pregnant or breastfeeding at screening; 10. Previously treated in this study (READY 2) or in study READY 1; 11. History of allergic reaction to reteplase or vial ingredients (excipients or diluents); 12. Use of any investigational drug or experimental medical device within 28 days prior to treatment; non interventional observational study participation is allowed; 13. Not mentally, socially or otherwise able to complete the trial assessments or not likely to survive beyond 30 days.