Xencor to Present Initial Data from the Phase 1 Study of Tidutamab in Neuroendocrine Tumors at NANETS' Multidisciplinary NET Medical Virtual Symposium

Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of cancer and autoimmune diseases, today announced that initial data from its ongoing Phase 1 dose-escalation study of tidutamab (XmAb^®18087), an SSTR2 x CD3 bispecific antibody, in patients with neuroendocrine tumors (NETs) will be presented during the upcoming North American Neuroendocrine Tumor Society's 2020 Multidisciplinary NET Medical Virtual Symposium.

Presentation Details

An abstract (#111) and a poster with initial data from the study will become available in the NANETS Virtual Poster Hall on Friday, October 2, 2020 at 9:00 a.m. ET.

The abstract was also selected to be presented in an oral session:

• Title: Preliminary Safety, PK/PD, and Antitumor Activity of XmAb18087, an SSTR2 x CD3 Bispecific Antibody, in Patients with Advanced Neuroendocrine Tumors
• Presenter: Bassel El-Rayes, M.D., Professor and Vice Chair for Clinical Research of the Department of Hematology and Medical Oncology at Emory University School of Medicine, as well as Director of the Gastrointestinal Oncology Program at Winship Cancer Institute
• Session: Clinical Abstracts
• Date & Time: Saturday, October 3, 2020, 2:00 p.m. ET

About Tidutamab

Tidutamab (XmAb^®18087) is a tumor-targeted bispecific antibody that contains both an SSTR2 binding domain and a T-cell binding domain (CD3). An XmAb^® bispecific Fc domain serves as the scaffold for the two antigen binding domains and confers long circulating half-life, stability and ease of manufacture on tidutamab. SSTR2 (somatostatin receptor 2) is an antigen highly expressed on some solid tumors, and engagement of CD3 by tidutamab activates T cells for highly potent and targeted killing of SSTR2-expressing tumor cells. Tidutamab is being evaluated in an ongoing Phase 1 study, which is enrolling patients with neuroendocrine tumors (NETs) and gastrointestinal stromal tumors (GISTs).

About Xencor, Inc.

Xencor is a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of cancer and autoimmune diseases. Currently, 18 candidates engineered with Xencor's XmAb^® technology are in clinical development internally and with partners. Xencor's XmAb antibody engineering technology enables small changes to the structure of monoclonal antibodies resulting in new mechanisms of therapeutic action. For more information, please visit www.xencor.com.

Forward-Looking Statements

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