Optimizing Therapy for Hairy Cell Leukemia - Episode 19
Robert J. Kreitman, MD: What’s your experience been with Moxe?
Farhad Ravandi-Kashani, MD: I’ve used moxetumomab pasudotox mainly on a clinical trial basis, and this was not only in hairy cell leukemia. We also conducted a small trial of moxetumomab in relapsed adult acute lymphoblastic leukemia. As you mentioned, there are many nuances about using this drug that you have to be aware and able to manage, particularly, capillary leak syndrome and hemolytic uremic syndrome.
But with the appropriate therapy this drug can be useful and effective. As you know, the current indication is for a patient who has had 2 prior lines of therapy, of which 1 has to have been a nucleoside analog. With that, what is your recommendation on how to use this drug and at what point of management of patients with hairy cell?
Robert J. Kreitman, MD: I think that in the third-line setting and greater, I would preferably use this drug before splenectomy. We found that the responses were better in patients who had not had prior splenectomy. I would also avoid patients who have massive lymphadenopathy. That tends to be less easy to treat with Moxe.
But we’ve been able to successfully treat patients who have very severe cytopenias and because we don’t tend to see worsening in cytopenias. I think that it works well in patients who have had prior purine analog and they tend to be cytopenic but don’t have an overwhelming burden of disease. Because there is what we call a binding site barrier, there are a lot of CD22 on the cells, and we’re not giving that many molecules of Moxe. Moxe can be all bound up the first few cycles, and the amount that’s in the blood is very low. All the tumor cells may not get access to the Moxe if there’s so much disease.
In that vein, I would just mention that we’re actually starting a trial now of Moxe plus rituximab in patients with at least a second-line need for treatment in hairy cell leukemia. But currently the approved indication for Moxe is at least in the third line.
Farhad Ravandi-Kashani, MD: In summary, there are now a number of different options available, particularly for patients who relapse after initial therapy. My advice to the community oncologist is that there are a number of centers that see these patients and have clinical trials for these patients, and who are very willing to operate and collaborate with you in selecting and administering the best therapy for patients with hairy cell leukemia, and are good resources—the Hairy Cell Leukemia Foundation—and I think with this we will continue to make further advances in treating patients with hairy cell leukemia, and hopefully there will be a time in the future that we will not even have relapses. Thank you.
Robert J. Kreitman, MD: I agree. I think that patients with hairy cell leukemia don’t necessarily need to be treated by a hairy cell expert. But I think they should get the advice of a hairy cell expert these days. It’s very critical now because we have so many different treatments, and it’s very hard for a general oncologist to decide on the right treatment. But I think once a patient does get an opinion, it’s certainly possible for a general oncologist to treat the patient.
But the other thing I would say is that clinical trials are also very important for patients with hairy cell leukemia. There’s an international hairy cell registry that patients should be encouraged to contribute to because it’s not a very common disease, and with more data, we can make improvements in the future treatment of hairy cell leukemia.
Transcript Edited for Clarity