Dr Prithviraj Bose Discusses Special Considerations for Use of JAK Inhibitors in Myelofibrosis

Prithviraj Bose, MD, of MD Anderson Cancer Center discusses the risk of patients being treated with JAK inhibitors developing non-Hodgkin lymphoma.

What are your thoughts on the special considerations included in the National Comprehensive Cancer Network’s guidelines for the use of JAK inhibitors in myelofibrosis?

You know, for the use of [ruxolitinib] we’ve had these special considerations listed in the guidelines and the new ones I believe just came out for fedratinib. One issue I’d like to touch on is that those controversial reports, I think a year or so ago, from Europe talking about the possibility of JAK inhibitor therapy leading to an increased risk of non-Hodgkin lymphoma. And while it was a general JAK inhibitor—related phenomenon as the authors put it, the vast majority of their patients, in fact, had ruxolitinib, obviously, because that is/was the approved drug.

So, that has been mentioned in the special considerations, but the reason I bring it up is that we already know that lymphoma is more common in patients with myeloproliferative neoplasms. Several groups including ours have shown that. And, specifically, after this report got published, we looked at our experience at MD Anderson and published, actually in the same journal—both reports are in Blood—that this is not the case. We did not see an increased risk of non-Hodgkin lymphoma in our ruxolitinib-treated patients as opposed to those who did not receive ruxolitinib. So, we do not feel this to be a real phenomenon, and I believe it is important for the NCCN guidelines to include both those points of view or, rather, both those pieces of data.

And also, the fact that the original study really refers to JAK inhibitors as a whole, so if at all, this were an effect, it would be a class effect, and not just for one drug. However, I don’t really feel there is a real risk there at all.