Xencor Presents Preclinical Data from Multiple XmAb Research Programs at the SITC Annual Meeting

Xencor, Inc. (NASDAQ: XNCR), a clinical-stage biopharmaceutical company developing engineered antibodies and cytokines for the treatment of cancer and autoimmune diseases, today presented data from multiple preclinical-stage XmAb programs at the 38th Annual Meeting of the Society for Immunotherapy of Cancer (SITC) in San Diego.

“Xencor aims to stay on the leading edge of molecular engineering, using and improving upon our XmAb technologies to create molecules with enhanced functionality or new therapeutic mechanisms. At SITC, we are presenting new preclinical data from two research-stage programs—engineered, decoy-resistant IL18-Fc fusions and our multi-valent NK cell engagers targeted to MICA and MICB, which are tumor antigens upregulated in the tumor microenvironment,” said John Desjarlais, Ph.D., executive vice president and chief scientific officer at Xencor. “Later this year, we expect to submit an investigational new drug application for XmAb541, an XmAb 2+1 format CLDN6 x CD3 bispecific antibody that we are developing for patients with ovarian cancer and other tumor types. We are also developing additional CD3 and CD28 T cell engaging bispecific antibodies against solid tumor targets.”

Posters will be available in the poster hall and virtually to registrants of the SITC Annual Meeting. In the poster hall, odd-numbered posters will be displayed on Friday, November 3, and even-numbered posters will be displayed on Saturday, November 4. Xencor’s posters will be archived under "Events & Presentations" in the Investors section of the Company's website located at www.xencor.com.

Clinical Trials in Progress

Abstract 764, “A Phase 1, first-in-human (FIH), open-label, dose-finding and expansion study of XmAb808, a B7H3 x CD28 bispecific antibody, in combination with pembrolizumab in patients with advanced solid tumors”

Xencor is conducting a Phase 1 study of XmAb808 in patients with advanced solid tumors. XmAb808 is a tumor-selective, co-stimulatory XmAb 2+1 bispecific antibody designed to bind to the broadly expressed tumor antigen B7-H3 and selectively to the CD28 T-cell co-receptor only when bound to tumor cells, which was demonstrated in vitro. Strong potentiation of checkpoint and CD3 cytotoxic activity was also observed in vivo. XmAb808 is a wholly owned Xencor program.