Non-immunogenic staphylokinase in patients with massive intermediate-high risk pulmonary embolism: protocol of the FORPE-2 multicenter, double-blind, randomized, placebo-controlled trial

Aim. To evaluate the efficacy and safety of single bolus administration of non-immunogenic staphylokinase in comparison with placebo in patients with intermediatehigh risk pulmonary embolism (PE) within the FORPE-2 clinical trial.

Material and methods. Non-immunogenic staphylokinase has high thrombolytic activity and fibrin selectivity. The FORPE-2 clinical trial has a multicenter, doubleblind, randomized, placebo-controlled design. In clinical sites, patients (486 in total, with a possible 10% dropout rate) with confirmed PE and evidence of right ventricular dysfunction based on computed tomography pulmonary angiography and an increased risk of hemodynamic instability (intermediate-high-risk PE) will be equally randomized into two groups to receive non-immunogenic staphylokinase or placebo. The study protocol provides inclusion and exclusion criteria, calculation of the required patient sample size, and the study plan. The primary efficacy endpoint will be a composite of all-cause mortality, hemodynamic collapse, and recurrent PE within 30 days of randomization. Safety endpoints will be hemorrhagic stroke during hospitalization and BARC type 3 and 5 bleeding types.

Results. The study will provide data on the efficacy and safety of non-immunogenic staphylokinase in patients with intermediate-high risk PE. A report will be compiled with individual data and statistical analysis of the results.

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