Almost everything about the new blood-thinning drug, dabigatran (Pradaxa) is novel.
In February, I wrote about the drug’s unusually short (thirty-day) expiration time. This week, the FDA has released a new communication concerning dabigatran. It included practical safety tips for patients, pharmacists and doctors, and is nicely summarized by Larry Husten, on Cardiobrief.
Here are a few of the more important points that jump out at me:
- Now, the FDA says that the potency of dabigatran is sixty days, not thirty.
- The potency of the drug relates to exposure to humidity. Dabigatran capsules should be left in the pre-packaged bottle and the lid closed tightly when not in use. This means the capsules should not be placed in pill boxes, nor should they be dispensed in regular amber pill vials.
- Patients who get ninety-day supplies of dabigatran should label the three bottles, and not open them until they are ready to start that month.
At first glance, you might think all this detail constitutes too much minutia.
Let me make two points:
For most patients, the strongest selling point of dabigatran is not its superior effectiveness in preventing stroke, but its convenience. Keep in mind that AF-patients with stroke risk factors often take other medicines. Something I learned from helping an elderly neighbor with her medicines is the complexity of compliance with multi-drug regimens. Though the short expiration dates, need for sealed containers and prohibition of organizing pill boxes aren’t deal-breakers, they certainly decrease the convenience gap between dabigatran and warfarin.
In the use of dabigatran as a potent blood-thinner, doctors are clearly in the getting-used-to-phase. We know that dabigatran is superior to warfarin for AF patients that require a blood thinner. But the thing that we all are wrestling with is the notion of not being able to measure the thinness of the blood. “How do you know the blood is thin,” is a question that always comes up. The answer is: if the patient takes the dabigatran capsule (as directed) the blood is appropriately thin. This very new (and novel) paradigm emphasizes the importance of patient compliance. For dabigatran to be effective, real-world patients have to mirror the closely scrutinized patients that participate in clinical trials.
I am still solidly behind dabigatran, as are many of my heart-rhythm colleagues.
In fact, as of this writing, I have successfully done more than a few atrial ablations on patients taking dabigatran.