REDSTEM – Reduced dose systemic thrombolysis in high-risk pulmonary embolism management: a multicenter randomized controlled double-blinded trial

High-risk pulmonary embolism (PE) is associated with high mortality and treatment challenges.

First-line therapy, systemic thrombolysis (ST), carries significant bleeding risks including intracerebral hemorrhages when the recommended full dose is used. In clinical practice, a lower dose is often given even though it lacks support.

Data suggest that lower doses of ST could be as effective and may reduce bleeding complications, but a Cochrane analysis of ST in PE recently concluded that high quality studies on treatment safety are needed.

The planned randomized controlled trial fills this knowledge gap by investigating safety outcomes of reduced versus full dose ST. Study planning is ongoing and is expected to be finalized by the end of 2025, with trial initiation in 2026. During 2025, the study protocol and statistical analysis plan will be completed.

The application to the Clinical Trials Information System for ethical and medical products agency approval will be submitted.

Clinical Studies Sweden will be consulted for project leadership, monitoring and data management, including implementation of an electronic case report form. Results from our ongoing observational multicenter study will inform sample size calculations. Establishment of a local and national multidisciplinary PE network has already commenced.

The planned study will provide crucial evidence to update clinical guidelines and improve patient outcomes, nationally and internationally shortly after study closure.