There is inadequate evidence to draw strong conclusions on the efficacy or safety of the drug interventions included in this review. There is some low quality evidence from a meta-analysis of two studies investigating urokinase (various strengths) and some very low evidence from two single studies investigating alteplase 2 mg/2 mL that suggest that these two drug interventions may be effective in treating withdrawal or total occlusion of CVC lumens caused by thrombosis. Further high quality, sufficiently powered research is still required to look at the efficacy and safety of urokinase, alteplase and other chemical, surgical and drug interventions for treating CVC lumen occlusion. Research studies which exclusively include child participants are especially warranted.
Dose-ranging trial with a recombinant urokinase (urokinase alfa) for occluded central venous catheters in oncology patients.
Recombinant urokinase (r-UK) is a high-molecular-weight urokinase produced in transfected, non-human, mammalian cells. A Phase II, randomized, double-blind, parallel, placebo-controlled, dose-ranging study was performed to compare the safety and efficacy of one or two instillations of three intraluminal concentrations of r-UK (5,000; 15,000; and 25,000 IU/mL) with a placebo for reestablishment of total function to occluded central venous access devices (CVADs).
                One-hundred eight patients with CVAD withdrawal or total occlusion were enrolled and randomized to treatment; 104 patients received at least one instillation of study drug and 101 patients completed treatment. All but one patient had cancer.
                All three concentrations of r-UK were significantly superior to placebo in restoring total CVAD function (patency of all occluded lumens) after one or two instillations of study medication (25,000 IU/mL r-UK, 68% vs. placebo, 28% [P =.007]; 15,000 IU/mL r-UK, 69% vs. placebo, 24% [P =.004]; 5,000 IU/mL r-UK, 70% vs. placebo, 28% [P =.003]). Comparisons of the three r-UK concentrations indicated no difference after one or two instillations with regards to patency restoration. Treatment-emergent hemorrhagic events occurring within 72 hours after study drug exposure were experienced by four patients (17%) in the 25,000 IU/mL r-UK group, two patients (7%) in the 15,000 IU/mL r-UK group, no patients in the 5,000 IU/mL r-UK group, and no patients in the placebo group.
                Efficacy and safety results of this study support further evaluation of a 5,000 IU/mL concentration of r-UK for treatment of occluded CVADs in adult and pediatric patients from 1 year of age.