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, will be included in several oral and poster presentations investigating the clinical significance of minimal residual disease (MRD) assessment at the American Society of Clinical Oncology (ASCO) Annual Meeting taking place June 2-6 in Chicago, as well as the European Hematology Association (EHA) Hybrid Congress taking place June 8-11 in Frankfurt, Germany. Data will be presented from clinical trials and real-world evidence studies using Adaptive’s next-generation sequencing (NGS)-based clonoSEQ® Assay for MRD assessment across a range of hematologic cancers.

“The clinical trial and real-world evidence that is being presented this year at ASCO and EHA showcase clonoSEQ’s utility as the gold standard in MRD assessment both to inform clinical decision making and help assess deep responses to novel therapeutics in patients with hematologic cancers,” said Nitin Sood, chief commercial officer, MRD, at Adaptive Biotechnologies. “Adaptive has demonstrated the value of NGS-MRD assessment in hematologic cancers. The use of MRD assessment in clinical trials and practice continues to mount, and we are pleased to see new data generated that attest to its benefit for physicians, patients and researchers alike.”

MRD can be used to assess depth of response and detect early signs of relapse prior to clinical symptoms. This assessment is performed as a series of tests in clinical trials and throughout a patient’s cancer journey. The clonoSEQ Assay is the first and only NGS-MRD test authorized by the U.S. Food and Drug Administration (FDA) for MRD assessment in certain hematologic malignancies. The assay is also offered as a CLIA-validated laboratory developed test for assessing MRD in diffuse large B-cell lymphoma (DLBCL).

The clinical findings presented at both ASCO and EHA highlight the prognostic value and clinical actionability of precise, sensitive MRD assessment in hematologic cancers utilizing the clonoSEQ Assay.

• In various stages of multiple myeloma (MM), real-world evidence and clinical trial results reinforce the clinical significance of sustained MRD negativity and depth of response in the prediction of patient outcomes, including overall survival and progression free survival (PFS).
• In adults with acute lymphoid leukemia (ALL), real-world evidence found a higher rate of residual disease detection by clonoSEQ as compared to detection with flow cytometry. This data underscores the highly accurate, sensitive and standardized properties of clonoSEQ as compared to other technologies used to assess disease burden.
• Data continues to show the potential for MRD assessment to help in the personalization of cancer care. For example, interim data in older patients with DLBCL demonstrated that the use of MRD assessment from ctDNA with clonoSEQ in combination with imaging has potential to inform treatment decisions to shorten the duration of therapy.
• Final analysis from the multi-center Phase 2 MASTER trial showed that in newly diagnosed MM patients treated with quadruplet therapy and monitored using clonoSEQ, the three-year PFS was higher in patients with sustained MRD negativity compared to those who did not achieve MRD negativity. Furthermore, 73% of patients that discontinued therapy based on their MRD status remained free of therapy with sustained MRD negativity. The MASTER trial has been key for studying the feasibility of an MRD-informed approach to treatment discontinuation. The final outcomes reinforce that patients who achieve MRD negativity over time, as measured by clonoSEQ, may be able to discontinue treatment to find relief from treatment side effects and enable substantial savings for the health care system.  
• Presentations will also highlight the value of utilizing NGS-MRD testing in clinical trials to assess the effectiveness of investigational, novel therapeutics.

Key ASCO 2023 Presentations

Presentation Type and Number	Title	Presentation Timing
Multiple Myeloma
Oral Abstract 8001	Maintenance therapy with carfilzomib, pomalidomide, and dexamethasone (KPd) in high-risk myeloma patients (pts): A phase 2 study with a safety run-in	Saturday, June 31:15-4:15 p.m. CDT
Poster Abstract 8028	Measurable residual disease (MRD) and clonal diversity for multiple myeloma treatment monitoring	Monday, June 58:00-11:00 a.m. CDT
Poster Abstract 8029	Long-term outcomes with isatuximab-carfilzomib-dexamethasone (Isa-Kd) in relapsed multiple myeloma patients with 1q21+ status: Updated results from the phase 3 IKEMA study	Monday, June 58:00-11:00 a.m. CDT
Poster Abstract 8031	Baseline and early post-infusion biomarkers associated with optimal response to idecabtagene vicleucel (ide-cel) in the KarMMa-3 study of triple-class–exposed (TCE) relapsed and refractory multiple myeloma (RRMM)	Monday, June 58:00-11:00 a.m. CDT
Poster Abstract TPS8066	MagnetisMM-7: An open-label, multicenter, randomized phase 3 study of elranatamab versus lenalidomide in post-transplant patients with newly diagnosed multiple myeloma	Monday, June 58:00-11:00 a.m. CDT
Poster Abstract 8009	CARTITUDE-1 final results: Phase 1b/2 study of ciltacabtagene autoleucel in heavily pretreated patients with relapsed/refractory multiple myeloma	Monday, June 53:00-4:30 p.m. CDT
Acute Lymphoblastic/Lymphoid Leukemia
Oral Abstract 7007	A phase I trial of dose-adjusted EPOCH plus inotuzumab ozogamicin (InO) in adults with relapsed/refractory (R/R) B lymphoblastic leukemia/lymphoma (B-ALL)	Friday, June 21:00-4:00 p.m. CDT
Poster Abstract 7033	Comparison of next-generation sequencing and flow cytometry in detecting minimal residual disease in adult acute lymphoid leukemia: Evaluating clinical outcomes in a single-center study	Monday, June 58:00-11:00 a.m. CDT
Non-Hodgkin’s Lymphoma
Poster Abstract 7554	Phase II trial of split-dose R-CHOP for older patients with diffuse large B-cell lymphoma (DLBCL)	Monday, June 58:00-11:00 a.m. CDT

Key EHA 2023 Presentations

Presentation Type and Number	Title	Presentation Timing
Multiple Myeloma
Poster Abstract P931	Isatuximab in relapsed multiple myeloma patients with ultra-high-risk cytogenetics: ICARIA-MM and IKEMA subgroup analysis	Friday, June 96:00 p.m.-7 p.m. CEST
Poster Abstract P871	Idecabtagene vicleucel (ide-cel) in patients with an inadequate response to frontline autologous stem cell transplantation (ASCT): results from KARMMA-2 cohort 2C	Friday, June 96:00 p.m.-7:00 p.m. CEST
Oral Abstract S203	Quadruplet induction therapy, ASCT and MRD-modulated consolidation and treatment cessation in newly diagnosed multiple myeloma: final analysis of the MASTER trial	Saturday, June 102:45 p.m.-4:15 p.m. CEST
Chronic Lymphocytic Leukemia
Poster Abstract P620	Genetic alterations and outcomes with fixed-duration ibrutinib+venetoclax (Ibr+Ven): results from the Phase 3 GLOW study in patients with previously untreated CLL	Friday, June 96:00 p.m.-7:00 p.m. CEST

About the clonoSEQ AssayThe clonoSEQ Assay 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. Medicare covers clonoSEQ in these four indications and is aligned with clinical practice guidelines which support assessing MRD at multiple time points throughout therapy to monitor treatment response and help predict patient outcomes.

The clonoSEQ Assay 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 therapy over time, monitor patients during remission, and predict potential relapse. 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 the clonoSEQ Assay 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.

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ADAPTIVE MEDIAErica Jones, Associate Director, Corporate Communications206-279-2423media@adaptivebiotech.com

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