SOURCE: Patient-Centered Outcomes Research Institute

Patient-Centered Outcomes Research Institute

September 27, 2016 15:00 ET

PCORI Board Approves Nearly $15 Million for Large Trial Comparing Risks, Benefits of Blood-Thinning Drugs for Blood Clots

Project Compares Drugs Head-to-Head for Effectiveness in Preventing Clot Recurrence

WASHINGTON, DC--(Marketwired - September 27, 2016) - The Patient-Centered Outcomes Research Institute (PCORI) Board of Governors today approved $14.8 million to fund a study of two newer blood-thinning medications. The study will compare the two drugs against each other and against the older drug warfarin to see which works best in preventing the recurrence of dangerous blood clots in the veins and lungs.

This randomized controlled trial will compare each drug's safety and effectiveness in helping people who have suffered a potentially deadly blood clot and are at high risk for another. The trial also seeks to provide evidence on the risks and benefits of taking blood thinners for longer than three months. Researchers plan to recruit more than 3,000 participants in as many as 60 sites.

Blood thinners, or anticoagulants, prevent the production of certain proteins that blood uses to clot. Although effective treatments long used to manage deep vein thrombosis and pulmonary embolism, or blood clots in the legs and lungs, these drugs can also cause serious bleeding. Moreover, no research has been done to compare the effectiveness of these drugs for extended treatment.

"This newly approved study adds significantly to our portfolio in this area by employing the 'gold standard' of randomized treatment assignment," said PCORI Chief Science Officer Evelyn P. Whitlock, MD, MPH. "Altogether, the research we are supporting will provide needed information to patients and their clinicians about balancing the risk of blood clot recurrence with the risk of bleeding for newer blood-thinning medications, and will support better-informed, patient-centered decision-making."

The new randomized controlled trial complements two observational studies on the effectiveness of several newer anticoagulants that PCORI's Board approved for funding this past summer. Both studies compare four new oral anticoagulants to warfarin in the extended treatment of deep vein thrombosis and pulmonary embolism, exploring important subgroups of interest including older adults and people with kidney disease. These studies, along with the project approved today, will add to the body of evidence necessary to help patients and those who care for them make evidence-based choices about which of these medications may best meet their needs.

With this latest award, PCORI's Board has approved more than $1.5 billion in funding since 2012 for 551 patient-centered comparative clinical effectiveness (CER) studies and related projects to enhance the methods and infrastructure needed to support rigorous, efficient CER. All awards are approved pending completion of a business and programmatic review by PCORI staff and completion of a formal award contract.


The Patient-Centered Outcomes Research Institute (PCORI) is an independent, nonprofit organization authorized by Congress in 2010. Its mission is to fund research that will provide patients, their caregivers and clinicians with the evidence-based information needed to make better-informed healthcare decisions. PCORI is committed to continuously seeking input from a broad range of stakeholders to guide its work.

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