What Are the Long-Term Side Effects of FCR CLL Treatment?

Experts responded to listener questions during our January 13, 2023 virtual town hall. Watch the full webinar here.

Jeff:    

Nick would like to know what are the main issues facing long-term CLL patients who did an FCR protocol?

Dr. Wierda:    

You know, I think probably the biggest risk is their disease coming back and needing to be retreated. That happens more often and is predictable in patients who have an unmutated immunoglobin gene. Work that Dr. Keating did and others here demonstrated that about half the patients who have a mutated immunoglobin gene who receive standard FCR treatment will remain in remission more than 10 years. And so that’s the subgroup of patients who are doing very well with FCR treatment. And it’s the unmutated cases that are at risk for relapse of their disease and ultimately developing resistance even to the targeted therapies.

I think, the other thing that we worry about is other cancers that can be caused by exposure of the bone marrow to the chemotherapy that you get with FCR. Those are AML, acute myeloid leukemia, or plastic syndrome. That happens – in our long-term follow-up that Dr. Thompson is summarizing now, that happens about 6 percent of the time overall for all patients that we treated here for FCR100 trial. About 6 percent. With the long 20 years of follow-up, we have developed MDS or AML. So, it’s a small number, but it’s not insignificant. It is a risk with that treatment, and I think that that’s what most of us worry about with that exposure.