Krish Patel, MD, Director of the Lymphoma Program at the Swedish Cancer Institute in Seattle and Interim Director of the Hematological Malignancies and Cellular Therapy Program, commented on the implications of Dr. Soumerai’s presentation.

“We know that, in general, reaching [undetectable measurable residual disease (MRD)] is correlated with long-term outcomes in chronic lymphocytic leukemia (CLL). What is interesting is that Dr. Soumerai and colleagues defined the ability to understand earlier In the course of treatment who will achieve undetectable MRD in the blood and bone marrow. They looked at MRD in the blood at 4 months, and at a later point, they looked at the bone marrow. Using the commercial, widely available assay called ClonoSEQ, they were able to define a cutpoint [ie, delta MRD400], which basically allows, with relatively high fidelity, identification of patients at 4 months into treatment who will then achieve undetectable MRD in the bone marrow. This is a very interesting biomarker,” Dr. Patel stated.

Krish Patel, MD

“Of note, they defined this biomarker in a very specific population—patients being treated with the triplet of zanubrutinib, obinutuzumab, and venetoclax. Further study is needed to see whether this biomarker is also applicable in other treatment paradigms—that is, other regimens with different drugs and with doublets and triplets. Also, further study is needed in larger populations of patients with CLL,” he continued. 

“In summary, delta MRD400 is a very interesting and promising biomarker that needs to be validated in other treatment settings,” Dr. Patel noted. 

DISCLOSURE: Dr. Patel has served as a consultant or advisor for AstraZeneca, Genentech, BeiGene, Pharmacyclics, Bristol-Myers Squibb/Celgene/Juno, Morphosys, Kite Pharmaceuticals, and TG Therapeutics; has served on a speakers’ bureau for Genentech, AstraZeneca, Pharmacyclics/Janssen, Bristol-Myers Squibb/Celgene, Kite Pharmaceuticals, and TG Therapeutics; and has received research funding from AstraZeneca, Sunesis Pharmaceuticals, Xencor, Pharmacyclics, Curis, Bristol-Myers Squibb, Celgene, Takeda, Aptevo Therapeutics, MEI Pharma, Trillium Therapeutics, Kite/Gilead, Roche/Genentech, and Fate Therapeutics.