Athenex Announces MHRA Decision on Oral Paclitaxel

• MHRA denies Oral Paclitaxel for metastatic breast cancer based solely on chemistry, manufacturing and control (CMC) issues
• Athenex plans to request a review of the MHRA decision by an independent panel
• The MHRA application was supplemented with safety data from the iSPY 2 study and no major clinical efficacy or safety concerns were expressed

BUFFALO, N.Y., Jan. 03, 2023 (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 that its proprietary Oral Paclitaxel formulation did not receive regulatory approval from the United Kingdom’s Medicines and Healthcare Products Regulatory Agency (MHRA) for metastatic breast cancer based solely on CMC issues. The MHRA application was not rejected based on any clinical efficacy or safety concerns expressed by the MHRA. MHRA regulations allow an applicant to request a re-examination of an opinion by an independent board which the Company plans to pursue. The Company views the identified CMC issues as addressable.

“While we are disappointed by the MHRA decision, we are encouraged that we have satisfactorily addressed any major concerns related to the clinical efficacy and safety of Oral Paclitaxel. We believe the iSPY 2 study is an important data set that further characterizes the safety profile of Oral Paclitaxel and we plan to amend our metastatic breast cancer NDA with the iSPY 2 safety data this quarter,” said Dr. Johnson Lau, Chief Executive Officer of Athenex. “To maximize the value of Oral Paclitaxel, we expect to re-engage the FDA by amending our metastatic breast cancer NDA with the iSPY 2 data, and pursue opportunities to advance development of Oral Paclitaxel in the neoadjuvant breast cancer setting in light of recent graduation of Oral Paclitaxel from the iSPY 2 program.”

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 and (2) Orascovery, based on a P-glycoprotein inhibitor. 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,” “mission,” “plan,” “will,” 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; 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 counterparty performance, including our reliance on third parties for success in certain areas of Athenex’s business; intellectual property risks, 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

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