Treatment initiation and management of comorbidities pose challenges for both pediatric and older adult patients with hemophilia A.
Jonathan Roberts, M.D.: Unique challenges to the pediatric population, really, especially when you talk about a new diagnosis, is what therapy are they going to be on and when to institute therapy. Certainly, if there’s a family history of hemophilia already and there’s been high morbidity such as an intracranial hemorrhage that may have occurred, we’re going to want to start therapy right away. Otherwise, the standard of care is to institute prophylaxis when a patient starts to have any type of bleeding symptoms. Typically, it would be a first joint [bleed] or first soft-tissue bleed. And then the decision is really, do we institute factor therapy or do we institute nonfactor therapy? We have comprehensive discussions about the different modes of administration, what’s been known, and what’s unknown. The nonfactor therapies have not been out as long, and there’s many still under clinical trials. So there are nuances with each of those. Some of them have not been yet looked at in the very young pediatric population, such as infancy and all of them are now being looked at. But there’s still a learning curve as to know what to treat with. The other thing is that in children, their metabolism for factor is much greater. So they tend to require higher units per kilo dosing. They may have a need for more frequent dosing intervals even with the extended half-life products. And that’s an important thing to understand from a managed health care and a payer perspective that if I or one of my colleagues are requesting higher doses per [kilogram] than maybe on a package insert, it may be because we’re tailoring it to the patient’s individual pharmacokinetic profile and they really need that more intensive therapy because they are metabolizing that factor a lot more rapidly. Again, when the end goal is to have patients experience no bleeds, it’s very important that we treat these patients appropriately. And in fact, preventing bleeds is by far the most important thing. There’s data to show that patients who are taken care of at comprehensive hemophilia treatment centers or bleeding centers like mine have reduced morbidity and mortality. They have better outcomes. That’s why I’m passionate about taking care of this population and directing patients to centers like ours, Centers of Excellence, that can help provide this expertise for managing patients.
The great thing is now for people with hemophilia A that we do have an aging population after the travesty of the HIV and hepatitis B and C era. Now, we have people that can live essentially a normal life expectancy with severe bleeding disorders from some of the most recent publications that have been out. Especially as we’re taking away a bleeding disorder per se, by having patients on prophylaxis, they can still have thrombosis from all the other risk factors that we have. And some of those may be a little bit higher with some of the nonfactor therapies because we are manipulating the coagulation system in different ways that may confer additional thrombotic risk. So that’s something that we have to talk about with patients. I have patients with mild hemophilia that have had cardiac events or may have atrial fibrillation, things like that, and we have them on anticoagulation or antiplatelet medicine in addition to their hemophilia treatment, which sounds counterintuitive, but it is necessary because coagulation is complex and we need to correct the deficit that the genetic disorder confers and then worry about the patient’s overall general health, other things like hypertension, hyperlipidemia, diabetes, metabolic syndrome, patients with bleeding disorders like severe hemophilia have a higher rate of being overweight. As you can imagine, if there’s preexisting joint damage from bleeding into joints, it makes mobility a challenge, and that snowballs into trouble with obesity and all the risk factors that go into that. The geriatric population is ripe for investigation. My colleagues and I are really trying to understand as we now have the benefit of having an aging hemophilia population, how to best treat them. What are some of the strategies and maybe [the] best evidence for [treating] some of these [patients? For instance, how should we address] anticoagulation in the face of a bleeding disorder that’s well treated? So these nuances require, expertise in hemophilia treatment centers from me and my colleagues across the country that do this every day.
Transcript edited for clarity.