Athenex Presents Interim Data from Phase 1 ANCHOR Study of KUR-502 (Allogeneic CD19 CAR-NKT Cells) in Relapsed or Refractory Lymphoma and Leukemia at the 2022 Transplantation & Cellular (“Tandem”) Meetings of ASTCT and CIBMTR

• Interim analysis provides response data from 7 evaluable patients including two additional patients, one with non-Hodgkin lymphoma (NHL) and one with acute lymphoblastic leukemia (ALL)
• Six-month CR rate of 29%, including 1 ongoing CR at 34 weeks in heavily pretreated patients
• Encouraging response rates at low doses: 57% overall response rate (ORR), 71% disease control rate (DCR)
• Two responses observed in patients who failed previous autologous CAR-T therapy
• Allogeneic CD19 CAR-NKT cells well tolerated with 3 cases of grade 1 cytokine release syndrome (CRS), no immune effector cell-associated neurotoxicity syndrome (ICANS) and no graft versus host disease (GvHD)
• Early responses at low doses suggest promise of “off-the-shelf” cancer immunotherapy platform

BUFFALO, N.Y., April 25, 2022 (GLOBE NEWSWIRE) — Athenex, Inc., (NASDAQ: ATNX), a global biopharmaceutical company dedicated to the discovery, development, and commercialization of novel therapies for the treatment of cancer and related conditions, today announced data from the ANCHOR Phase 1 study of KUR-502 during an oral presentation by Carlos Ramos, M.D., professor, Center for Cell and Gene Therapy, Baylor College of Medicine, at the Tandem Meetings of the American Society of Transplantation and Cellular Therapy (ASTCT), and the Center for International Blood & Marrow Transplant Research (CIBMTR), taking place April 23 to 26, in Salt Lake City, UT.

“Encouraging data from the interim update of the ANCHOR study further support the promising efficacy and favorable safety profile of KUR-502 in heavily pretreated patients with hematological malignancies,” said Dan Lang, M.D., President of Athenex Cell Therapy. “It is exciting to see the therapeutic benefit of our CAR-NKT cell therapy persists as the ANCHOR study matures, particularly in patients who have already progressed on autologous CAR-T therapy. We intend to collect additional patient data as we expand the study to include more sites and look forward to providing another update later this year.”

Highlights from the interim update include response data from seven evaluable patients, including two additional patients who were previously too early to assess (1 NHL, 1 ALL):

• One patient with NHL had stable disease (SD), and a second patient with ALL had progressive disease (PD) at the 4-week assessment
• Two CRs persisted for more than 6 months with one at 34 weeks and still ongoing
• Two responses (1 CR and 1 PR) were observed in patients who had relapsed after previous autologous CAR-T therapy
• Excellent safety with no immune effector cell-associated neurotoxicity syndrome (ICANS) and no graft versus host disease (GvHD) attributable to CAR-NKT cells
• Grade 1 cytokine release syndrome (CRS) in 2 ALL patients

*Patient B1 from the ALL cohort had a complete response with incomplete hematologic recovery (CRi)

About the Phase I Study of KUR-502 (Allogeneic CD19 CAR-NKT Cells) in Patients with Relapsed or Refractory B-Cell Malignancies (ANCHOR)

The Phase 1 study is an open-label, dose-escalation trial. NKT cells were isolated from the leukapheresis product of one HLA-unmatched healthy individual, transduced with the CAR, expanded ex vivo for 14 days (99.8% NKT purity), and cryopreserved. Subjects were treated in an outpatient setting and received 10⁷ (DL 1) or 3×10⁷ (DL 2) CAR-NKT cells per square meter of body surface area following lymphodepleting conditioning with cyclophosphamide/fludarabine. Adverse events were evaluated per NCI criteria. When accessible, patients underwent core biopsies of an involved site at 2-5 weeks post-infusion. Response to therapy was assessed at 4 weeks per Lugano Criteria (for NHL) or NCCN guidelines (for ALL).

For further information about the study, visit ClinicalTrials.gov, identifier: NCT03774654. The abstract “Allogeneic NKT Cells Expressing a CD19-Specific CAR in Patients with Relapsed or Refractory B-Cell Malignancies” presented at the 2022 Transplantation & Cellular Tandem Meetings of ASTCT and CIBMTR can be viewed here.

About Athenex, Inc.

Founded in 2003, Athenex, Inc. is a global clinical-stage biopharmaceutical company dedicated to becoming a leader in the discovery, development, and commercialization of next generation cell therapy drugs for the treatment of cancer. In pursuit of this mission, Athenex leverages years of experience in research and development, clinical trials, regulatory standards, and manufacturing. The Company’s current clinical pipeline is derived mainly from the following core technologies: (1) Cell therapy based on NKT cells, (2) Orascovery, based on a P-glycoprotein inhibitor, and (3) Src Kinase Inhibition. Athenex’s employees worldwide are dedicated to improving the lives of cancer patients by creating more active, accessible and tolerable treatments. For more information, please visit www.athenex.com.

Forward-Looking Statements

Except for historical information, all of the statements, expectations, and assumptions contained in this press release are forward-looking statements. These forward-looking statements are typically identified by terms such as “believe,” “look forward to,” “potential,” and similar expressions. Actual results might differ materially from those explicit or implicit in the forward-looking statements. Important factors that could cause actual results to differ materially include: our history of operating losses and the substantial doubt about our ability to continue as a going concern; our strategic pivot to focus on our cell therapy platform and our plan to dispose of non-core assets; our ability to obtain financing to fund operations, successfully redirect our resources and reduce our operating expenses; our ability to refinance, extend or repay our substantial indebtedness owed to our senior secured lender; the development stage of our primary clinical candidates, including NKT Cell Therapy and related risks involved in drug development, clinical trials, regulation, uncertainties around regulatory reviews and approvals; the preclinical and clinical results for Athenex’s drug candidates, which may not support further development of such drug candidates; the Company’s ability to successfully demonstrate the safety and efficacy of its drug candidates and gain approval of its drug candidates on a timely basis, if at all; the uncertainty of ongoing legal proceedings; risks related to our ability to successfully integrate the business of Kuur into our existing businesses, including uncertainties associated with maintaining relationships with customers, vendors and employees, as well as differences in operations, cultures, and management philosophies that may delay successful integration and our ability to support the added cost burden of Kuur’s business; risks related to counterparty performance, including our reliance on third parties for success in certain areas of Athenex’s business; risks and uncertainties inherent in litigation, including purported stockholder class actions; the impact of the COVID-19 pandemic and other macroeconomic factors, like the war in Ukraine, and their ongoing impact on our operations, supply chain, cash flow and financial condition; competition; intellectual property risks; risks relating to doing business internationally and in China; the risk of development, operational delays, production slowdowns or stoppages or other interruptions at our manufacturing facility as well as our ability to find alternative sources of supply to meet our obligations and requirements; and the other risk factors set forth from time to time in our SEC filings, copies of which are available for free in the Investor Relations section of our website at http://ir.athenex.com/phoenix.zhtml?c=254495&p=irol-sec or upon request from our Investor Relations Department. All information provided in this release is as of the date hereof and we assume no obligation and do not intend to update these forward-looking statements, except as required by law.

Athenex Contacts

Investors

Daniel Lang, MD
Athenex, Inc.
Email: danlang@athenex.com

Caileigh Dougherty
Athenex, Inc.
Email: cdougherty@athenex.com