Cogent trial shows lack of adverse interaction between clopidogrel and stomach medicine

September 24, 2009

Results from a late breaking clinical trial called COGENT demonstrate that the combination of giving patients clopidogrel, a blood thinner commonly prescribed to patients with cardiovascular disease, and stomach medicines such as omeprazole, known as proton pump inhibitors (PPIs), did not lead to adverse events, as some prior studies had suggested. The results were presented at the 21st annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, sponsored by the Cardiovascular Research Foundation (CRF).

COGENT is the first randomized assessment of administering clopidogrel and PPIs, which reduce the production of gastric acid, on clinical events. The trial involved 3,627 patients at 393 sites. Follow up was limited due to early termination of the trial.

Internal bleeding is a common adverse effect of antiplatelet or blood thinner therapies, such as clopidogrel. The gastrointestinal tract is the most common location for this type of bleeding, which often occurs in the form of peptic ulcer disease. The purpose of the trial was to determine whether the administration of clopidogrel and omeprazole is safe and effective in reducing the incidence of gastrointestinal bleeding and symptomatic ulcer disease in the setting of concomitant aspirin therapy.

The primary endpoint of the trial was a composite of upper gastrointestinal clinical events, including gastroduodenal bleeding, symptomatic gastroduodenal ulcer, and persistent pain with multiple gastric erosions, obstruction or perforation.

There was a significant reduction in gastrointestinal events with PPI use. This had not been previously demonstrated in patients receiving aspirin and clopidogrel.

"Further research is needed to define the optimal strategy to reduce GI events in patients on antithrombotic therapy, though prophylactic PPI use seems promising," said lead investigator, Deepak L. Bhatt, MD, MPH, Chief of Cardiology at VA Boston Healthcare System and Director, Integrated Interventional Cardiovascular Program at Brigham and Women's Hospital and the VA Boston Healthcare System.

Source: Cardiovascular Research Foundation