Use of MRD in the CLL Space

Carolyn Owen, MD, associate professor in the Division of Hematology & Hematological Malignancies, University of Calgary, and hematologist at the Tom Baker Cancer Center, discusses minimal residual disease as an area of research.

Recently, Owen discussed the phase 3 GLOW trial (NCT03462719) which assessed fixed-duration ibrutinib (Imbruvica) and venetoclax (Venclexta) in the frontline for elderly or unfit patients with chronic lymphocytic leukemia (CLL). In the trial, treatment with ibrutinib and venetoclax led to deeper and prolonged undetectable minimal residual disease (uMRD) responses vs chlorambucil and obinutuzumab (Gazyva).

Still, Owen notes that more studies are needed to assess the ways MRD might help direct therapy and improve patient outcomes.

Transcription:

0:08 | I think that MRD is a very interesting area of research, but I think it continues to be an area of research and not really a routine clinical test that should be applied today. I think these results are very informative in telling us that if we had assessed for MRD at the end of therapy and known the result and altered our management based on it, that it might not have been a wise idea. The patients who have detectable MRD are doing just as well as the patients who have undetectable MRD, which is counterintuitive from our past results. But I do think that there's a bit of a desire to have the newest tests available to us. We need to know what to do with them before we use them.

0:52 | For this test, I think that there's no use for it right now with I plus V or other venetoclax based therapies that people are really motivated to use MRD. I think we need better studies to show us how that might help direct therapy and improve patient outcomes. There are a lot of clinical trials that use MRD to direct the duration of therapy, but there are very few that compare against a non-MRD directed outcome in which you could say at the end of the day that using MRD improved the outcome of the patient. I think that we would do well to design even bigger clinical trials, like cooperative group studies, and answer this question better because MRD itself is going to have cost implications, especially in places like the United States where there are many community [treatment centers], it might not be as easily available. People should know whether they should be obtaining this, whether it's a difficult test to get, and whether they should get it to help their patient if it's more than just an academic test that isn't going to change anything right now. I think that better directed clinical trials would help us answer that question.