Non-immunogenic Recombinant Staphylokinase vs Placebo in Patients With Intermediate High-risk Pulmonary Embolism

For patients with massive PE thrombolysis can be life-saving and may reduce a pulmonary obstruction, pulmonary hypertension, and right ventricle dysfunction. Efficacy of the thrombolytic therapy has been proven in patients with high-risk pulmonary embolism accompanied by shock or systemic hypotension. However, the question of whether thrombolytic therapy can improve the clinical outcome of hemodynamically stable patients, i.e. with PE of intermediate high-risk, still remains controversial.

In PEITHO trial tenecteplase, administered as a single bolus at a dose of 30-50 mg depending on body weight was compared with a placebo in patients with intermediate high-risk PE with right ventricular dysfunction. Efficacy of tenecteplase was combined with a significant (6.3%) risk of hemorrhagic stroke, which did not allow tenecteplase to be included in the list of recommended thrombolytics for PE treatment.

PEITHO-3 trial has now begun, in which patients with intermediate high-risk PE are given a reduced dose of alteplase (0.6 mg/kg infusion with the total dose not exceeding 50 mg) compared with placebo.

Staphylokinase is a thrombolytic agent with high biological activity. Amino acid substitutions - including Lys74Ala, Glu75Ala, and Arg77Ala - resulted in a more than 200-times reduction in titres of neutralising antistaphylokinase IgGs in patients with ST-elevation myocardial infarction. In FORPE trial non-immunogenic recombinant staphylokinase was non-inferior as compared with alteplase in patients with high-risk massive PE.

The main objectives of this study: to assess the efficacy, safety and possible adverse events of the non-immunogenic recombinant staphylokinase with its single bolus administration in normotensive patients with intermediate high-risk PE in comparison with placebo.