ADPT Adaptive Biotechnologies Corporation

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 that its next-generation sequencing (NGS)-based clonoSEQ® test for measurable residual disease (MRD) assessment will be included in several oral and poster presentations at the American Society of Clinical Oncology (ASCO) Annual Meeting taking place May 31-June 4 in Chicago and at the European Hematology Association (EHA) Hybrid Congress taking place June 13-16 in Madrid and virtually.

“The data that will be presented at ASCO and EHA this year build on the expansive evidence base supporting the clinical significance and actionability of MRD testing with clonoSEQ within the quickly evolving blood cancer treatment landscape,” said Susan Bobulsky, chief commercial officer, MRD, Adaptive Biotechnologies. “clonoSEQ continues to be the gold standard in MRD assessment, empowering clinicians with the most reliable insights to navigate complex treatment decisions and arming drug developers with a highly sensitive and standardized assay to confidently advance the most promising therapeutics.”

MRD status is a powerful predictor of outcomes in blood cancers. Routine MRD testing offers a personalized approach to monitor and evaluate an individual’s response to treatment, identify early signs of relapse before symptoms occur, and inform shared decision-making to optimize care. Beyond clinical applications, clonoSEQ assay technology is used extensively in drug development as a robustly validated tool to understand treatment efficacy and determine depth and kinetics of response. It is also increasingly being used as a primary endpoint in clinical trials.

The clinical trial data and real-world evidence to be presented at ASCO and EHA further underscore the clinical benefit of specific and sensitive MRD assessment with clonoSEQ. Highlights include:

• In a Children’s Oncology Group-led study of pediatric patients with acute lymphoblastic leukemia (ALL), evidence from the largest analysis to date comparing bone marrow MRD assessment to peripheral blood MRD assessment with clonoSEQ showed a strong correlation between blood and marrow, independent of patient risk group. These data support the potential for a less invasive method to monitor MRD and track a patient’s response to therapy in ALL.
• In various stages of multiple myeloma (MM), real-world evidence and clinical trial results reinforced the clinical significance of sustained MRD negativity and importance of depth of response in predicting patient outcomes, including overall survival (OS) and progression-free survival (PFS), and illustrated how clonoSEQ could inform treatment discontinuation or de-escalation decisions.
  • Follow-up data generated from the University of Chicago prospective MRD2STOP study indicated that MRD testing with clonoSEQ at 10–6 may help identify patients who can safely and effectively discontinue maintenance therapy and sustain MRD negativity off treatment.
  • An MRD analysis from the PERSEUS study, conducted by the Cancer Center Clinica Universidad de Navarra in Spain, compared bortezomib/lenalidomide/dexamethasone (VRd) with or without daratumumab (D) in transplant-eligible patients with newly diagnosed MM. MRD negativity at both 10–5 and 10–6 was associated with improved PFS. Of note, the higher rates of deeper responses (10–6) in the D-VRd/D-R arm were associated with a clinically meaningful benefit of improved PFS.
  • Multiple trials evaluating the safety and efficacy of novel chimeric antigen receptor T cell (CAR-T) therapies demonstrated the value of utilizing clonoSEQ to measure deep responses during or after therapy in often difficult-to-treat patient populations and showed MRD negativity as assessed by clonoSEQ testing is associated with PFS.
• In patients with chronic lymphocytic leukemia (CLL), data from clinical trials highlighted the use of clonoSEQ to support individualized MRD-guided treatment modification.

clonoSEQ-related data to be presented at both ASCO and EHA:

Presentation Type and Number	Title	Presentation Timing
B-Cell Acute Lymphoblastic Leukemia
ASCO Oral Presentation6504	Obecabtagene Autoleucel (Obe-Cel, AUTO1) In Adults With Relapsed/Refractory B-Cell Acute Lymphoblastic Leukemia (R/R B-ALL): Overall Survival (OS), Event-Free Survival (EFS) And The Potential Impact Of Chimeric Antigen Receptor (CAR)-T Cell Persistency And Consolidative Stem Cell Transplantation (SCT) In The Open-Label, Single-Arm FELIX Phase Ib/II Study	Friday, May 313:57–4:09 p.m. CDT
EHA Oral PresentationS114	Obecabtagene Autoleucel In Adult Relapsed/Refractory B Cell Acute Lymphoblastic Leukemia: Survival And Potential Impact Of CAR-T Cell Persistence And Stem Cell Transplantation In The FELIX Study	Friday, June 143:45–4 p.m. CEST
Multiple Myeloma
ASCO Oral Presentation7505	Efficacy And Safety Of Ciltacabtagene Autoleucel ± Lenalidomide Maintenance In Newly Diagnosed Multiple Myeloma With Suboptimal Response To Frontline Autologous Stem Cell Transplant: CARTITUDE-2 Cohort D	Monday, June 34:24–4:36 p.m. CDT
EHA Oral PresentationS205	Ciltacabtagene Autoleucel ± Lenalidomide Maintenance In Newly Diagnosed Multiple Myeloma With Suboptimal Response To Frontline Autologous Stem Cell Transplant: CARTITUDE-2 Cohort D	Saturday, June 154:30–4:45 p.m. CEST
ASCO Oral Presentation7510	Efficacy Of Venetoclax-Dexamethasone (Vendex) V Pomalidomide-Dexamethasone (Pomdex) In Patients (Pts) With T(11;14)-Positive Relapsed/Refractory Multiple Myeloma [T(11;14)+ RRMM]: Phase 3 CANOVA Study Biomarker Subgroup Analysis	Monday, June 34:24–4:36 p.m. CDT
EHA Poster PresentationP912	Efficacy Of Venetoclax-Dexamethasone V Pomalidomide-Dexamethasone In Patients With T(11;14)-Positive Relapsed/Refractory Multiple Myeloma [T(11;14)+ RRMM]:Phase 3 CANOVA Biomarker Subgroup Analysis	Friday, June 146 p.m. CEST
ASCO Oral Presentation7502	Daratumumab (DARA) + Bortezomib/Lenalidomide/Dexamethasone (VRd) In Transplant-Eligible (TE) Patients (Pts) With Newly Diagnosed Multiple Myeloma (NDMM): Analysis Of Minimal Residual Disease (MRD) In the PERSEUS Trial	Monday, June 33:24–3:36 p.m. CDT
EHA Oral PresentationS201	Daratumumab + Bortezomib/Lenalidomide/Dexamethasone in Transplant-Eligible Patients With Newly Diagnosed Multiple Myeloma: Analysis of Minimal Residual Disease in the PERSEUS Trial	Saturday, June 1511:45 a.m.–12 p.m. CEST
ASCO Oral Presentation7504	Ciltacabtagene Autoleucel Vs Standard of Care in Patients With Functional High-Risk Multiple Myeloma: CARTITUDE-4 Subgroup Analysis	Monday, June 34:12–4:24 p.m. CDT
EHA Poster PresentationP978	Ciltacabtagene Autoleucel Vs Standard of Care in Lenalidomide-Refractory Multiple Myeloma: Phase 3 CARTITUDE-4 Subgroup Analysis By Cytogenetic Risk	Friday, June 146 p.m. CEST

Additional data to be presented at ASCO:

Presentation Type and Number	Title	Presentation Timing
B-Cell Acute Lymphoblastic Leukemia
Oral Presentation10014	Comparison Of Immunoglobulin High-Throughput Sequencing MRD in Bone Marrow And Peripheral Blood In Pediatric B-ALL: A Report From The Children's Oncology Group AALL1731	Monday, June 312:54–1:06 p.m. CDT
Follicular Lymphoma
Oral Presentation7015	EPCORE NHL1 Follicular Lymphoma (FL) Cycle (C) 1 Optimization (OPT) Cohort: Expanding The Clinical Utility of Epcoritamab in Relapsed o-r Refractory (R/R) FL	Sunday, June 25:30–5:36 p.m. CDT
Multiple Myeloma
Oral Presentation106	Discontinuation of Maintenance Therapy in Multiple Myeloma Guided By Multimodal Measurable Residual Disease Negativity (MRD2STOP)	Monday, June 310:01–10:13 a.m. CDT
Oral Presentation7500	Phase 3 Study Results of Isatuximab, Bortezomib, Lenalidomide, And Dexamethasone (Isa-Vrd) Versus Vrd For Transplant-Ineligible Patients With Newly Diagnosed Multiple Myeloma (IMROZ)	Monday, June 33–3:12 p.m. CDT
Oral Presentation7501	Phase 3 Randomized Study of Isatuximab (Isa) Plus Lenalidomide And Dexamethasone (Rd) With Bortezomib Versus Isard in Patients With Newly Diagnosed Transplant Ineligible Multiple Myeloma (NDMM TI)	Monday, June 33:12–3:24 p.m. CDT
Poster Presentation7527	Association Of Patient (Pt) Factors And Pharmacodynamic Biomarkers With Progression-Free Survival (PFS) After Idecabtagene Vicleucel (Ide-Cel) In Pts From KarMMa-3	Monday, June 39 a.m.–12 p.m. CDT
Poster Presentation7535	Ciltacabtagene Autoleucel In Patients With Lenalidomide-Refractory Multiple Myeloma: CARTITUDE-2 Cohort A Expansion Subgroup	Monday, June 39 a.m.–12 p.m. CDT
Poster Presentation7557	Effect Of Dose-Adjusted Melphalan On MRD-Negativity To Full Dose Melphalan in Patients With Multiple Myeloma Post-Autologous Stem Cell Transplant	Monday, June 39 a.m.–12 p.m. CDT
Poster Presentation7560	Indirect Comparison of Linvoseltamab Versus Teclistamab For Triple-Class Exposed (TCE) Relapsed/Refractory Multiple Myeloma (RRMM)	Monday, June 39 a.m.–12 p.m. CDT

Additional data to be presented at EHA:

Presentation Type and Number	Title	Presentation Timing
B-Cell Acute Lymphoblastic Leukemia
Poster PresentationP413	Brexucabtagene Autoleucel (Brexu-Cel) As Consolidation Treatment in Adults With B-Cell Acute Lymphoblastic Leukemia With Marrow Blasts <5%, Including Patients (Pts) With NGS MRD Negative Disease	Friday, June 146 p.m. CEST
Chronic Lymphocytic Leukemia
Oral PresentationS164	Combined Pirtobrutinib, Venetoclax, And Obinutuzumab in First-Line Treatment of Patients With Chronic Lymphocytic Leukemia (CLL): A Phase 2 Trial	Friday, June 143:45–4 p.m. CEST
Poster Presentation P1837	Postinfusion Resource Use And Cost of Lisocabtagene Maraleucel By Response Status And Prior Lines of Therapy In Patients With Relapsed/Refractory Chronic Lymphocytic Leukemia From TRANSCEND CLL 004	Friday, June 146 p.m. CEST
Poster PresentationP672	A Phase 2 Study of Minimal Residual Disease (MRD)-Adapted, Time-Limited Acalabrutinib And Obinutuzumab For The Initial Treatment of Patients With Chronic Lymphocytic Leukemia (CLL): MRD Outcomes	Friday, June 146 p.m. CEST
Follicular Lymphoma
Oral PresentationS234	Epcoritamab Induces Deep Responses in Relapsed Or Refractory (R/R) Follicular Lymphoma (FL): Safety And Pooled Efficacy Data From EPCORE NHL‑1 Pivotal And Cycle (C) 1 Optimization (OPT) FL Cohorts	Saturday, June 155:30–5:45 p.m. CEST
Poster Presentation P1137	Undetectable Measurable Residual Disease (MRD) Is Associated With Improved Long-Term Outcome in Patients With Follicular Lymphoma (FL) Treated With Chemo-Immunotherapy: Results From SWOG S0016	Friday, June 146 p.m. CEST
Poster PresentationP2059	Minimal Residual Disease (MRD), Pharmacokinetic (PK), And Pharmacodynamic (PD) Assessment of Epcoritamab 2- Vs 3-Step Step-Up Dosing in Patients With Relapsed/Refractory Follicular Lymphoma (R/R FL)	Friday, June 146 p.m. CEST
Multiple Myeloma
Poster Presentation P974	Daratumumab (DARA)/Bortezomib/Lenalidomide/Dexamethasone (D-VRd) With D-R Maintenance (Maint) In Transplant-Eligible (TE) Newly Diagnosed Myeloma (NDMM): Analysis of PERSEUS Based On Cytogenetic Risk	Friday, June 146 p.m. CEST
Poster Presentation P943	Oral Ixazomib Maintenance Following Autologous Stem Cell Transplant (ASCT) In Patients With Newly Diagnosed Multiple Myeloma (NDMM): Final Overall Survival (OS) Analysis From The TOURMALINE-MM3 Study	Friday, June 146 p.m. CEST

About clonoSEQ

clonoSEQ is the first and only FDA-cleared in vitro diagnostic (IVD) test service to detect minimal residual disease (MRD) in bone marrow from patients with multiple myeloma (MM) or B-cell acute lymphoblastic leukemia (B-ALL) and blood or bone marrow from patients with chronic lymphocytic leukemia (CLL). clonoSEQ testing for diffuse large B-cell lymphoma (DLBCL) patients is currently available for clinical use as a laboratory-developed test (LDT) performed at Adaptive's CLIA-certified lab in Seattle, WA.

clonoSEQ leverages Adaptive Biotechnologies’ proprietary immune medicine platform to identify and quantify specific DNA sequences found in malignant cells, allowing clinicians to assess and monitor MRD during and after treatment. The assay provides standardized, accurate, and sensitive measurement of MRD that allows physicians to predict patient outcomes, assess response to treatment, inform changes in therapy, monitor disease burden over time, and detect potential relapse early. Clinical practice guidelines in hematological malignancies recognize that MRD status is a reliable indicator of clinical outcomes and response to therapy, and clinical outcomes have been shown to be strongly associated with MRD levels measured by clonoSEQ in patients diagnosed with CLL, MM, ALL, and DLBCL.

For important information about the FDA-cleared uses of clonoSEQ, including the full intended use, limitations, and detailed performance characteristics, please visit www.clonoSEQ.com/technical-summary.

About Adaptive BiotechnologiesAdaptive 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, autoimmune disorders, and infectious diseases. Our goal is to develop and commercialize immune-driven clinical products tailored to each individual patient.

Forward Looking Statements This press release contains forward-looking statements that are based on management’s beliefs and assumptions and on information currently available to management. All statements contained in this release other than statements of historical fact are forward-looking statements, including statements regarding our ability to develop, commercialize and achieve market acceptance of our current and planned products and services, our research and development efforts, and other matters regarding our business strategies, use of capital, results of operations and financial position, and plans and objectives for future operations.

In some cases, you can identify forward-looking statements by the words “may,” “will,” “could,” “would,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “ongoing” or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. These statements involve risks, uncertainties and other factors that may cause actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. These risks, uncertainties and other factors are described under "Risk Factors," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and elsewhere in the documents we file with the Securities and Exchange Commission from time to time. We caution you that forward-looking statements are based on a combination of facts and factors currently known by us and our projections regarding the future, about which we cannot be certain. As a result, the forward-looking statements may not prove to be accurate. The forward-looking statements in this press release represent our views as of the date hereof. We undertake no obligation to update any forward-looking statements for any reason, except as required by law.

ADAPTIVE INVESTORSKarina Calzadilla, Vice President, Investor Relations201-396-1687investors@adaptivebiotech.com

ADAPTIVE MEDIAErica Jones, Associate Corporate Communications Director206-279-2423media@adaptivebiotech.com