To evaluate the safety profile of alfimeprase as assessed by monitoring of adverse events, serious adverse events and major bleeding events for up to 120 minutes following the instillation of study drug to an occluded central venous access device.

Further study details as provided by Nuvelo

Inclusion Criteria:

• Must give written informed consent
• Ages 18 or older
• Unable to withdraw at least 3 mL of blood from a central venous access device
• Hemodynamically stable
• Available for follow-up assessments

Exclusion Criteria:

• Inability to infuse at least 2 mL of saline through the catheter
• Catheter placed less than 48 hours prior to detection of occlusion
• Catheter used for hemodialysis or pheresis
• Previous treatment with plasminogen activator for current episode of catheter occlusion
• Less than 18 years of age
• Any evidence of mechanical or nonthrombotic occlusion
• In the opinion of the investigator, subject is at "high risk" for bleeding events of embolic complications, or has a condition for which bleeding constitutes a significant hazard
• Increased risk for drug extravasation
• Pregnant, lactating, or actively menstruating women and women of child-bearing potential who are not using adequate contraceptive precautions (e.g., intrauterine device, oral contraceptives, barrier methods, or other contraception deemed adequate by the investigator)
• Known right-to-left cardiac shunt, patent foramen ovale, or atrial/ventricular septal defect
• Participation in any other study of an investigational device, medication, biologic, or other agent within 30 days before enrollment and until the 30-day follow up visit
• Any other subject feature that in the opinion of the investigator should preclude study participation