Xencor Presents Updated Data From the DUET-2 Phase 1 Study of XmAb20717, PD-1 x CTLA-4 Bispecific Antibody, at the SITC Annual Meeting

Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of cancer and autoimmune diseases, today reported data from its ongoing Phase 1 study evaluating XmAb20717, a PD-1 x CTLA-4 bispecific antibody and Xencor’s first tumor microenvironment activator, in patients with advanced solid tumors (DUET-2). The preliminary results from the study’s expansion cohorts will be presented in a poster titled, “Preliminary safety, pharmacokinetics/pharmacodynamics, and antitumor activity of XmAb20717, a PD-1 x CTLA-4 bispecific antibody, in patients with advanced solid tumors” at the 35th Annual Meeting of the Society for Immunotherapy of Cancer (SITC) by Elaine Shum, M.D., Assistant Professor in the Division of Medical Oncology and Hematology at the NYU Perlmutter Cancer Center.

“We are observing activity across multiple tumor types in patients who have already been treated with a checkpoint inhibitor, a difficult-to-treat patient population,” said Bassil Dahiyat, Ph.D., president and chief executive officer at Xencor. “XmAb20717 continues to be tolerable throughout our expansion cohorts, and importantly in our study we are observing lower rates of some types of immunotherapy-related adverse events, including colitis, than are typically seen with CTLA-4 blockade.”

“Though data are early, we are especially encouraged by initial activity in patients with metastatic castration-resistant prostate cancer. In the first half of 2021, we plan to initiate a Phase 1b study of XmAb20717 for patients with certain molecular subtypes of mCRPC, as a monotherapy or in combination depending on the subtype, as these patients represent a high unmet medical need,” said Allen Yang, M.D., Ph.D., senior vice president and chief medical officer at Xencor. “We are also planning additional cohorts in selected populations within DUET-2, based on clinical activity and unmet medical need. Data are also still maturing in cohorts of patients with renal cell carcinoma, and those with cancers without approved checkpoint therapies, including prostate cancer. We will provide further updates in the coming months.”