Boehringer’s Blood Thinner Dabigatran (Pradaxa) Unanimously Endorsed

Dabigatran binds to thrombin, its protein target. (Boehringer-Ingelheim)

After last week’s Meridia and Lorqess drama, I could’ve really used some good news from an FDA panel. And on Monday, I got it- in the form of a unanimous endorsement for a new blood thinner. The drug getting the love is dabigatran etexilate, which was developed by family-owned Boehringer Ingelheim and will be marketed as Pradaxa if approved. It’s one of a cadre of drugs trying to replace warfarin (also known as coumadin), a medication that has been on the market for over 50 years and is among the most difficult to manage.

Warfarin prevents formation of blood clots and can reduce ongoing clots. Doctors prescribe it to prevent painful leg clots in patients getting hip or knee replacements, to prevent stroke in patients with an abnormal heart rhythm called atrial fibrillation, and more. We recently wrote about how warfarin is a dirt cheap and effective medication, but it interacts with a plethora of foods, herbal supplements, and other drugs.

Pradaxa is already approved in several countries outside the U.S. for short-term use, preventing leg clots in patients getting hip or knee replacements. The drug blocks thrombin, a protease enzyme that sits near the end of the complex biochemical pathway known as the coagulation cascade. Just about all of the drugs being developed to replace warfarin, at least the ones toward the end of the pipeline, target either thrombin or Factor Xa, the protein immediately before thrombin in the pathway.

FDA’s cardiovascular and renal drugs advisory committee voted 9-0 in favor of approving Pradaxa for preventing stroke in patients with atrial fibrillation. (Boehringer-Ingelheim press release) This will be a longer-term stint on Pradaxa than post-hip or knee surgery patients typically experience. So the most important part of the panel’s discussion, to me, was their assessment of the drug’s effects on the liver. That’s because in 2006, another thrombin blocker called ximelagatran, developed by AstraZeneca, was pulled from the market because of liver toxicity. When you dig into the briefing documents that FDA provided to the panel, you find this blurb on page 103:

Based on these data, the risk of severe drug induced liver injury from dabigatran appears to be low. Because the perceived risk is low and frequent liver monitoring may not prevent serious cases from occurring (even if an association did exist), regular monitoring of liver tests is not recommended.

So it seems that ximelagatran’s liver issues may not be a class-wide problem. Still to be determined is what doses of the drug might be approved- read this post by Pharmalot for an assessment of why doses matter. FDA is expected to make its call on Pradaxa by Oct. 19. And in related clot-stopping news: at a November conference, Bayer and Johnson & Johnson will release data on their blood thinner, rivaroxaban (Xarelto), in atrial fibrillation patients. Xarelto is a Factor Xa inhibitor that, like Pradaxa, is approved in other countries for short-term use.

Thanks to Shelley Wood of heartwire at theheart.org for live-tweeting this panel.

Author: Carmen Drahl

Share This Post On

8 Comments

  1. Wonder about the cost of the drug and whether it will be covered under Medicare Part D?

  2. My INR nurse told me about this new drug today…sounds awesome! She says it WILL be more expensive that Warafin but she didn’t know how much more.

  3. Pradaxa is $260 a month in Canada. It’s hopeful the cost will come down once it is indicated more for life-long therapies like stroke and DVTE prevention.

  4. Can Prodaxa also be prescribed for patients with prosthetic heart valves? I have been doing my own pro-times for the last 3 years….but I am really tired of the constant montoring and the effect of diet changes on Coumadin…even an occaisional social drink can send my pro-time up to unsafe levels.

  5. Are there limits on what one eats and drinks when taking Prodaxa?

  6. I have Leiden Factor V,hav been on coumedin for 15 years.

    I wonder if I would be able to switch to Pradaxa?

  7. Her doctor has just prescribed Pradaxa for my mother, who is in a nursing home following hip surgery and has a stubborn blood clot in her leg that has not responded to Coumadin. Her doctor is hopeful that Pradaxa will break up the clot, as well as prevent future ones. Any experience with this particular application?

  8. Using Prodaxa are y0u limited or restriced to certain foods. Does it restrict one in having an occational wine with dinner, or an occational cocktail? Thank you