Adaptive Biotechnologies Showcases Leadership in Hematology-Oncology MRD with New clonoSEQ® Data Driving Treatment Interventions at 2025 ASH Annual Meeting

SEATTLE, Dec. 06, 2025 (GLOBE NEWSWIRE) — Adaptive Biotechnologies Corporation (Nasdaq: ADPT), a commercial stage biotechnology company that aims to translate the genetics of the adaptive immune system into clinical products to diagnose and treat disease, announced growing interventional use of its clonoSEQ^® test among the 90 abstracts featuring clonoSEQ data at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition, taking place Dec. 6–9, 2025, in Orlando. Notably, 17 abstracts utilizing Adaptive’s clonoSEQ^® test exemplify how next-generation sequencing-based measurable residual disease (MRD) status is guiding clinical actions to improve blood cancer patient care.

Practice-changing data from the phase II EndRAD study support the use of NGS MRD status prior to allogeneic hematopoietic cell transplantation (HCT) to guide the selection of non-total body irradiation (TBI) conditioning approaches to reduce long-term toxicities in children and young adults with B-cell acute lymphoblastic leukemia (B-ALL), without compromising outcomes. The study showed outstanding event-free and overall survival outcomes in 51 patients who were NGS MRD negative and received a non-TBI regimen. The study also enrolled a comparator cohort who received TBI and showed equivalent survival in NGS MRD negative patients who received TBI (the current standard of care) compared to non-TBI approaches (oral presentation, abstract 163).

“For young people facing leukemia, the impact of treatment doesn’t end when therapy does,” said Michael Pulsipher, M.D., Division Chief of Hematology, Oncology and Bone Marrow Transplantation at Primary Children’s Hospital and Huntsman Cancer Institute at the University of Utah. “The EndRAD results demonstrate that, for NGS MRD-negative patients, we may be able to choose transplant approaches without radiation that support both survival and long-term well-being—an advancement with real, lasting impact for patients and their families.”

Across hematologic malignancies, clonoSEQ MRD status is used by health care providers as an interventional tool to guide clinical decisions at key points in care. The presentations below show how investigators are applying clonoSEQ MRD results to tailor treatment intensity or duration with greater precision.

Multiple Myeloma (MM)

• A total of 32 abstracts will be presented (31 MM, one smoldering MM), with a focus on MRD assessment of treatment response, real-world data demonstrating the link between MRD status and clinical outcomes, and several studies describing how clonoSEQ MRD results are being used to guide treatment decisions.
• A presentation focused on MRD dynamics in the phase III AURIGA study of 200 newly diagnosed MM patients demonstrated that deep MRD responses and sustained MRD negativity correlated with improved progression free survival. The study shows that use of intensified maintenance in MRD-positive patients post-transplant doubled MRD negativity rates (oral presentation, abstract 97).

Non-Hodgkin Lymphoma (NHL)

• Fifteen abstracts in NHL will be presented, focusing on use of MRD to better understand depth of response and to guide therapy.
• In diffuse large B-cell lymphoma (DLBCL), results from a phase II Wisconsin Oncology Network study which used clonoSEQ to de-escalate therapy in frail older adults with DLBCL will be presented (poster presentation, abstract 1964). Additionally, data supporting the integration of ctDNA into post–CAR T surveillance will be presented (oral presentation, abstract 941).
• Results from a phase II, MRD-guided study in older mantle cell lymphoma (MCL) patients demonstrate the use of clonoSEQ to guide duration of frontline BOVen therapy (zanubrutinib, obinutuzumab, venetoclax) (oral presentation, abstract 888).

Chronic Lymphocytic Leukemia (CLL)

• Seven abstracts utilizing clonoSEQ MRD will be presented, with the majority leveraging the test to assess treatment response and guide treatment discontinuation.
• Data from a Phase II study of 80 patients with previously untreated CLL showed that time-limited pirtobrutinib, venetoclax, and obinutuzumab (PVO) achieved notably deep and durable remissions based on MRD assessment at a threshold of 10^-6. MRD positive status using clonoSEQ was used to identify patients who may continue therapy, highlighting clonoSEQ as a potential tool for guiding treatment duration in this regimen (oral presentation, abstract 680).

Acute Lymphoblastic Leukemia (ALL)

• In addition to the EndRAD trial, 30 ALL abstracts will be presented describing the use of clonoSEQ to assess treatment response in investigator studies and real-world data, as well as analyses describing comparisons of bone marrow and peripheral blood MRD by clonoSEQ.

“The unprecedented volume and diversity of data at ASH this year further solidifies clonoSEQ’s leadership in the field of blood cancer MRD monitoring,” said Susan Bobulsky, chief commercial officer, MRD, Adaptive Biotechnologies. “Our unmatched body of clinical evidence and real-world patient experience, together with meaningful updates across lymphoid cancer clinical practice guidelines over the past year, reflect clear recognition of the test’s value in accelerating therapeutic progress and strengthening MRD-informed patient management.”

About clonoSEQ^®
clonoSEQ^® is the first and only FDA-cleared in vitro diagnostic (IVD) test for detecting and tracking minimal (or measurable) residual disease (MRD) in patients with multiple myeloma (MM) or B-cell acute lymphoblastic leukemia (B-ALL) using bone marrow, and in patients with chronic lymphocytic leukemia (CLL) using blood or bone marrow. clonoSEQ is also available in diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL) and other lymphoid cancers and specimen types as a CLIA-validated laboratory developed test (LDT). clonoSEQ is covered by Medicare for MM, CLL, ALL, DLBCL and MCL.

clonoSEQ identifies and quantifies DNA sequences in malignant cells—detecting one cancer cell in one million healthy cells—to help clinicians and researchers assess and monitor MRD with precision over time. It delivers standardized, sensitive results that inform treatment decisions, predict outcomes, and detect relapses earlier.

clonoSEQ is CE-marked under the EU In Vitro Diagnostic Regulation (IVDR). For intended use details in the EU, see the instructions for use, available on request. To review the FDA-cleared uses of clonoSEQ, visit clonoSEQ.com/technical-summary.

About Adaptive Biotechnologies
Adaptive Biotechnologies (“we” or “our”) is a commercial-stage biotechnology company focused on harnessing the inherent biology of the adaptive immune system to transform the diagnosis and treatment of disease. We believe the adaptive immune system is nature’s most finely tuned diagnostic and therapeutic for most diseases, but the inability to decode it has prevented the medical community from fully leveraging its capabilities. Our proprietary immune medicine platform reveals and translates the massive genetics of the adaptive immune system with scale, precision and speed. We apply our platform to partner with biopharmaceutical companies, inform drug development, and develop clinical diagnostics across our two business areas: Minimal Residual Disease (MRD) and Immune Medicine. Our commercial products and clinical pipeline enable the diagnosis, monitoring, and treatment of diseases such as cancer and autoimmune disorders. Our goal is to develop and commercialize immune-driven clinical products tailored to each individual patient.

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