New Study: Pradaxa Users at Risk for Viral Infections

The UNC study was published in the The Journal of Clinical Investigation in March 2013. It shows that Pradaxa blocks a an integral part of the blood clotting system that may leave Pradaxa users more susceptible to serious viral infections such as the flu and myocarditis — when the middle layer of the heart wall becomes inflamed often due to a viral infection. Myocarditis can lead to blood clots forming in the heart, resulting in a heart attack or stroke — a serious threat to the lives of children and young adults.

Up until 2010, the only blood thinner available was warfarin, sold under the brand names Coumadin and Jantoven. The problem with warfarin is that it puts users at risk for severe bleeding and it doesn’t interact well with other types of medications, including over-the-counter supplements, and some foods, requiring regular blood tests. Pradaxa was introduced as an alternative to warfarin that does not come with any food restrictions nor does it require regular blood tests.

Despite being hailed as a new wonder drug, however, Pradaxa has been linked to severe and even life-threatening side effects, including uncontrollable internal bleeding and hemorrhaging. Unlike warfarin, Pradaxa was released onto the market without a bleeding antidote, leading to the deaths of hundreds of Pradaxa users.

Pradaxa works by blocking thrombin activity. Thrombin is the body’s central clotting agent, but Pradaxa disturbs the normal process that usually occurs in blood clotting. While this thins the blood, as is intended, it ends up weakening the immune system.

“Our findings show that blocking thrombin reduces the innate immune response to viral infection. The use of the new generation of blood thinners might increase the risk and severity of flu and myocarditis,” said Nigel Mackman, the senior author of the study and director of the UNC McAllister Heart Institute.

The blood clotting system plays a key role in fighting against viruses. Mackman explains that studies seemed to point to fibrin — the protein that forms in the last step in the clotting process as the key process in activating the immune system. Fibrin forms the strands that add bulk to a blood clot as its developing, so that the blood clot stays in place. What Mackman’s study shows is that it’s the thrombin activity that is key in fighting viruses, not the fibrin.

“But it seems that the antiviral mechanism of the clotting system is not via fibrin but rather via thrombin; namely, its activation of protease activated receptor proteins such as PAR-1. The new study was aimed at finding out if PAR-1 plays any role in virus infections, a question of importance to the use of Pradaxa–and the development of antithrombotic drugs that target PAR-1 on platelets,” said Mackman.

The researchers used mice in their study and were surprised by the outcome.

“The results we generated were completely unexpected and in fact our hypothesis was that PAR-1 deficient mice would be protected from viral myocarditis because they would have reduced inflammation,” said Marckman.

The question for researchers now is if this is unique to antithrombin blood thinners or if warfarin will have the same effect on viral infections.

If you or someone you know has experienced negative side effects from taking Pradaxa, legal options are available. Learn more and get a free legal consultation regarding a claim’s eligibility at the Pradaxa Internal Bleeding Class Action Lawsuit Investigation. Experienced legal professionals have access to medical experts to assess whether or not this blood thinner played a role in a serious event such as internal bleeding, hemorrhaging or even death, so act now.