A pilot trial of microplasmin in patients with long-term venous access catheter thrombosis.
BACKGROUND
Microplasmin, a truncated form of plasmin, degrades fibrin and reacts with the circulating inhibitor alpha(2)-antiplasmin. We investigated the safety and efficacy of intra-catheter microplasmin bolus administration for the restoration of catheter function in long-term venous access catheter thrombosis.


METHODS
This open-label, ascending-dose, pilot study enrolled 31 subjects. Two doses of microplasmin were evaluated, (5 mg and 8 mg) administered via a 2 ml intra-catheter bolus injection in 10 and 21 patients respectively. Catheter function was evaluated 30 min after the first bolus administration. In case of incomplete catheter function restoration, a second bolus was administered with reassessment of catheter function 30 min thereafter.


RESULTS
After the first bolus, complete restoration of catheter withdrawal function was observed in 5 out of 10 (50%) and 14 of out 21 (66%) subjects treated with 5 mg and 8 mg respectively and in 8 out of 10 (80%) and 18 out of 21 (86%) subjects after a second administration of microplasmin. No bleeding complications nor other adverse events were related to microplasmin.


CONCLUSIONS
In this pilot trial, microplasmin restored catheter function in a safe and effective way.
Verhamme
Peter
P
Department of Vascular Medicine and Haemostasis, University Hospitals Leuven, Catholic University Leuven, Herestraat 49, 3000, Leuven, Belgium. Peter.Verhamme@uz.kuleuven.be
Jerome
Martine
M
Goossens
Godelieve
G
Devis
Joanna
J
Maleux
Geert
G
Stas
Marguerite
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002405:Catheterization, Central Venous / Q000009:adverse effects*; D002408:Catheters, Indwelling / Q000009:adverse effects; D015331:Cohort Studies; D005260:Female; D005341:Fibrinolysin / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000627:therapeutic use*; D010865:Pilot Projects; D013997:Time Factors; D020246:Venous Thrombosis / Q000188:drug therapy* / Q000209:etiology*; D055815:Young Adult
D010446:Peptide Fragments; C054561:microplasmin; D005341:Fibrinolysin