Dr. John Leonard
Management
So, with respect to regulatory interactions, that's something that we don't want to characterize at this point in time. And as we have a more complete picture, we'll share that when we think it's pertinent. With respect to hemophilia B, and more broadly, I would say, with respect to gene insertion, which we relate to gene therapy, we think that there's very significant advantages to the approach that we're advancing here. So, step back and remember what gene therapy is. Typically, what you're trying to do is deliver a transgene, often in form of a virus, which persists in the cell for some period of time as an episome, in dividing cells that can be lost and it can be lost even in non-dividing cells. So, the durability of that effect, it seems and seems to be corroborated by some clinical data that's been emerging is incomplete. I mean, it doesn't appear to be lifelong. So, when we think about the advantage that we can bring, particularly the disease, like hemophilia, which manifests in childhood, a permanent insertion that one hopes normalizes, or very, very significantly improves on existing therapy that a child can grow up with, represents a very significant advantage, we think over the episome approach that just is not ideally suited for that patient population. And as we know, in hemophilia, a lot of the damage occurs in youngsters, and that is lifelong. So, we're excited about having that kind of an outcome. And that's the endgame for a program like this. And, again, we're starting in the early stages here, but that's the destination.