That 30% of all the hospital admission bleeds on anticoagulants now are associated with a factor Xa inhibitor, low-molecular-weight heparin injectable, or the orals and that is going to continue to grow. That is going to continue to grow. It is growing at a rate that we would have predicted from the Phase 3 clinical trials. It is not just the rate at which they are being admitted, but who are these patients? What is the morbidity? Jason, you asked about how you are going to profile these patients to determine who really needs it?
We are going to start to understand a little bit more about the morbidity of these patients, mortality of these patients. We are just learning about it. The costs associated with these patients. The top tier of about 15% of patients, cost of $100,000 to treat these patients. These are expensive patients for a hospital and it causes morbidity and mortality. That is what we are trying to address. We believe we are really setup to monetize around 500,000 patients who may benefit from an antidote by 2020.
The question for us is do we target all 500,000 of those or do we target a narrower group? Because we have more benefit, there is more urgency, we can get more adaption. We have more pricing leverage. Those decisions we will make over the next 12 to 18 months. I think most of you know the mechanism of action modified a version of human factor Xa; two modifications made to it primarily to render it not procoagulant or anticoagulant. The good thing is that it is very, very specific – very, very specific –it is different than anything else that is being developed, not only based on its specificity as a recombinant protein but also its half-life. You basically can turn this on and turn it off. We think that is really, really important because of its onset of action which is immediate and its pharmacodynamic half-life which is fairly short. You can almost turn it on and off. In the acute setting, that is all clinicians want, a little bit of control. I think it is specificity and it is on-and-off rate or something unique to anything being developed. I think it is one of the reasons we were granted breakthrough status by the FDA.
This is the conditional, when you say pivotal trials for conditional approval. Right now, we completed two of them, Eliquis and Xarelto, randomized patients who are in steady state, not patients but healthy volunteers who are on steady-state factor Xa inhibitor to andexanet or placebo and measure its ability to reverse the anticoagulant activity measured by primarily factor Xa inhibitor units and also on a secondary basis, normalization of thrombin generation. We do a short duration and a longer duration. Just to mirror what we think is going to be needed in the clinical practice.
This is the data from what was called ANNEXA-A. This is the reversal of Andexanet on the left hand margin. These are anti-Xa units. This is the validated enzymatic activity of the factor Xa inhibitors. This is concentration that is of the atrial fibrillation dose of apixaban at steady-state. You can see at the first time, you measured after the completion of the infusion. It is roughly to well below 90%. All 24 of 24 subjects are greater than 90% reversal. The consistency, look at the arrow bars around that. That is important because you are going to look at some other agents that are being used. What is important is look at the margin of arrow around this drug given as a bolus followed by infusion.
