Key Opinion Leaders Underscore Importance of MRD Testing in Multiple Myeloma

Testing for minimal residual disease (MRD) is increasingly being used in patients with cancer, particularly for blood cancers like multiple myeloma (MM), because of its association with treatment outcomes. For example, deep MRD negativity is associated with better patient outcomes. The measure has also found popularity among providers for its use in helping make decisions regarding treatment.

The clinical significance of MRD status was recently highlighted in The American Journal of Managed Care^® (AJMC^®)’s Peer Exchange Series “A Review of the Treatment for Multiple Myeloma.” During the series, key opinion leaders discussed the clinical implications and significance of MRD testing in patients with MM.

For Rafael Fonseco, MD, a hematologist at the Mayo Clinic, MRD testing is used in 2 scenarios: prognostic at day 100 post stem-cell transplant and in patients who have long-term sustained complete responses (CRs). For the latter group, MRD status opens up the conversation about discontinuation of therapy.

Andrzej Jakubowiak, MD, PhD, professor of medicine and director of the Myeloma Program at the University of Chicago Medicine, agreed with the idea of potentially discontinuing maintenance therapy in patients with sustained CRs. He explained, “We believe that at some point we will learn that a patient who has sustained MRD-negativity for a year or 2, or more, will be able to be approaching this question, ‘Can we stop or not?’”

He added that in a way, UChicago Medicine is trying to predict this by already collecting the data through yearly checks on patients’ CRs.

“I think it’s perfectly fine to discontinue therapy in someone who has had a sustained CR with MRD negativity at 2 or 3 years,” added Fonseco. “The person could have stopped therapy even without doing the testing, but it just adds information.”

However, there are some unanswered questions regarding how to properly make decisions based on MRD status. For example, when discussing the role of maintenance therapy in MM, John Fox, MD, MHA, vice president of Clinical Transformation at Spectrum Health, said, “I think the real challenge is not understanding how long you need to be on maintenance therapy if you’re in MRD or if you’re MRD negative.”

In an interview with AJMC^®, Fox explained that in the last decade, there have been approximately 5 or 6 drugs approved for MM and even more combinations of drugs, which has caused challenges with understanding how to best use these options. In addition to making decisions on the duration of maintenance therapy based on MRD status, “we need more information about what the role of transplant is, especially in an era where we have very high MRD-negativity,” he said.

During the video series, other key opinion leaders also echoed these unknowns and highlighted the need for more data and evidence in order for physicians to implement more widespread use of the measure.