A brief review of the role of tagraxofusp as bridging therapy to stem cell transplant in patients diagnosed with blastic plasmacytoid dendritic cell neoplasm.
Bhumika Patel, MD: The efficacy data of tagraxofusp in first-line blastic plasmacytoid dendritic cell neoplasm [BPDCN], [is something] we’ve briefly talked about. If the patient is optimal, we would use tagraxofusp as our first-line therapy for them. The bridge to transplant after CR1 [first complete response] has an overall response of around 50%. What are your thoughts about that efficacy? Because I think that’s pretty good for where we stand with this rare entity.
Thomas Leblanc, MD: Yes, these numbers are pretty impressive. On this trial in first-line patients, about a third of these patients overall were bridged to transplant. But then when you look at the ones who achieved a CR [complete response] or a CRc [composite complete remission], it’s 51%. So basically half of the patients who got into a CR went on to transplant. That is really impressive. When I reflect on my AML [acute myeloid leukemia] practice, which is a sizable part of what I spend my clinical time doing, we don’t get 50% of our patients with AML to transplant. And with most patients with AML being older and having intermediate or even high-risk disease, transplant is indicated for most of those people. Even when we want to get most of them to transplant, it’s probably more like 20%, 25%, 30% maybe who end up going. So this is quite impressive.
The thing to remember though is that this was a clinical trial, and so you always have that issue of patients being a bit more selected for a clinical trial. And this may not reflect what will end up happening in the real-world setting, where perhaps we have more barriers to transplantation that usually are honestly logistical, financial, caregiver-related kinds of issues, more so than things like finding appropriate donors, which is not nearly as much of a problem these days with alternative donor transplants. But it’s pretty exciting to see how many people were bridged to transplant with this therapy, and I think that’s a big part of why it is the first-line recommended therapy now because it’s so much more effective at getting people to the thing that does change long-term outcomes with this disease.
Bhumika Patel, MD: I think Dr Leblanc, the other standard therapies for patients with severe BPDCN were very cytotoxic. The difference with tagraxofusp is that it’s very targeted, so we’re not causing more toxicities to these patients, which may be one of the other reasons why patients can be bridged to transplant and are getting a durable remission with this disease. To your point, I agree, this is an exciting first-line therapy for patients, and I think we’re improving care for them.
Thomas Leblanc, MD: That is a great point, Dr Patel. Sometimes our treatments are so difficult that we just beat patients up too much, and then they’re not in [good enough] shape to be able to get the transplant they need. I see that a lot with AML treatments and ALL [acute lymphocytic leukemia] therapies in especially older patients who might be kind of on the cusp of transplant candidacy, people who maybe you’d give a reduced-intensity transplant to if they were going to get one at all. And if we hurt them too much with the therapy that aims to get them into remission, then we can basically take away that transplant option if they’re not fit enough for it anymore. I think that’s one of the great advantages of tagraxofusp, it being a more tolerable therapy aside from the issues with a capillary leak syndrome.
Bhumika Patel, MD: Right. And I think to your point, in the patients who are not fit, there are not many treatment options. There are limited palliative intent therapies, and even clinical trials may not be an option, and more localized treatments are being used like steroids, and radiation, and that’s if it’s only skin involvement. Otherwise, it is a lot of supportive care for these patients when they’re not candidates for intensive regimens in their treatment course.
Thomas Leblanc, MD: Absolutely.
Transcript edited for clarity.