News Releases

Apr 20, 2016
OncoMed Presents Biomarker Research for Two Clinical Programs and Demcizumab Mechanism Data at the AACR Annual Meeting 2016

REDWOOD CITY, Calif., April 20, 2016 (GLOBE NEWSWIRE) -- OncoMed Pharmaceuticals Inc. (NASDAQ:OMED), presented new biomarker research associated with its clinical programs for anti-RSPO3 (OMP-131R10) and vantictumab (anti-FZD7, OMP-18R5), as well as new preclinical mechanism-of-action data for demcizumab (anti-DLL4, OMP-18M21), at the American Association of Cancer Research (AACR) Meeting.  All three presentations support ongoing clinical trials:  anti-RSPO3  in a Phase1a/b trial in advanced solid tumor and colorectal cancer; vantictumab  in a Phase 1b trial in pancreatic cancer; and demcizumab  in a Phase 2 randomized study in first-line non-small cell lung cancer (NSCLC).

Based on preclinical work in patient-derived xenograft models that demonstrated a correlation between RSPO3 gene expression and anti-RSPO3 antibody efficacy, researchers at OncoMed set out to develop predictive biomarker assays.  A CLIA-validated RSPO3 assay and a gene fusion detection workflow have both been developed and are now being deployed in OncoMed's Phase 1a/1b dose escalation study of anti-RSPO3 in advanced solid tumors and in combination with FOLFIRI in metastatic colorectal cancer.  Data detailing the validation of the predictive biomarker tests were presented in Abstract 404:  "Development of a RSPO3 CLIA-validated assay as a predictive biomarker for response to anti-RSPO3 antibody treatment in patients with solid tumors".

Abstract 3129: "Predictive biomarker identification for response to vantictumab (OMP-18R5; anti-Frizzled) using primary patient-derived human pancreatic tumor xenografts" reviewed the identification of a distinct three-gene signature as a predictive biomarker for response to vantictumab combined with gemcitabine plus Abraxane.  The three-gene biomarker has been validated in multiple patient-derived xenograft models and is now being utilized in an ongoing Phase 1b study of vantictumab in combination with standard-of-care therapy in patients with previously untreated Stage IV pancreatic cancer. 

"Whenever possible, we strive to identify and validate possible predictive biomarkers that may be able to serve as companion diagnostics early on in the clinical development process.  We are optimistic about the correlation observed between RSPO3 gene expression and anti-RSPO3's efficacy and have begun using these assays in our ongoing Phase 1a/1b clinical trial," said Ann Kapoun, PhD, Vice President, Translational Medicine.  "Vantictumab is another candidate that has proven amenable to the identification of predictive biomarkers.  In addition to the three-gene pancreatic assay now being utilized in our Phase 1b clinical trial, last year we presented data on a six-gene biomarker for breast cancer, which is also now being assessed in the clinic.  Data from our ongoing clinical trials of anti-RSPO3 and vantictumab are anticipated later in 2016."

Anti-DLL4 was evaluated in a series of NSCLC patient-derived xenografts to model demcizumab treatment in humans as a single-agent and in combination with standard-of-care carboplatin/pemetrexed.  Data presented detailed anti-DLL4's multi-pronged mechanism of action.  Notch pathway and stem-cell related genes were down-regulated and a decrease in tumor-initiating cells was observed in anti-DLL4-treated tumors.  Evidence of anti-DLL4's vascular mechanism of action was affirmed by observations of up-regulation of endothelial-related genes, increases in blood vessel density and modification of hypoxia-related gene expression.  Studies in humanized mice, created by engraftment of human hematopoietic stem cells with patient-derived xenograft tumors allowed researchers to observe an increase anti-DLL4's immune activity in the presence of human lymphocytes, including up-regulation of human CD45+ cells and down-regulation of human CD33+ cells in tumors.  Anti-DLL4 showed tumor growth inhibition and the combination with chemotherapy demonstrated improved activity.  These findings provide additional evidence supporting demcizumab as a potential treatment for NSCLC.  Data were presented in Abstract 4652: "Effects of anti-DLL4 treatment on non-small cell lung cancer (NSCLC) human xenograft tumors".  A Phase 2 trial (DENALI) testing demcizumab in combination with chemotherapy is currently enrolling.

About OncoMed Pharmaceuticals
OncoMed Pharmaceuticals is a clinical-stage company focused on discovering and developing novel anti-cancer stem cell and immuno-oncology therapeutics.  OncoMed has seven anti-cancer therapeutic candidates in clinical development, including demcizumab (anti-DLL4, OMP-21M18), tarextumab (anti-Notch2/3, OMP-59R5), brontictuzumab (anti-Notch1, OMP-52M51), anti-DLL4/VEGF bispecific antibody (OMP-305B83), vantictumab (anti-FZD7, OMP-18R5), ipafricept (FZD8-Fc, OMP-54F28), and anti-RSPO3 (OMP-131R10), which each target key cancer stem cell signaling pathways including Notch, Wnt and R-spondin LGR.  OncoMed is advancing its wholly owned GITRL-Fc candidate and an undisclosed immuno-oncology candidate (IO#2) toward clinical trials in the 2016-2017 timeframe.  OncoMed has formed strategic alliances with Celgene Corporation, Bayer Pharma AG and GlaxoSmithKline (GSK). 

Additional information can be found at the company's website:

Forward-Looking Statements
To the extent that statements contained in this press release are not descriptions of historical facts regarding OncoMed Pharmaceuticals, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, including OncoMed's expectations regarding the correlation between RSPO3 gene expression and anti-RSPO3's efficacy; the utility of OncoMed's three-gene signature as a predictive biomarker for response to vantictumab; the mechanism of action of demcizumab; the potential effectiveness of demcizumab as a treatment for NSCLC; and the timing of advancement of GITRL-Fc and IO#2 to clinical trials. Such forward-looking statements involve substantial risks and uncertainties that could cause OncoMed's clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainties inherent in the preclinical and clinical development process; OncoMed's dependence on its collaboration partners, including Celgene, GSK and Bayer, for the funding of its partnered programs; OncoMed's ability to raise additional capital to support the development of its unpartnered programs; OncoMed's reliance on third parties to conduct certain preclinical studies and all of its clinical trials; OncoMed's reliance on single source third-party contract manufacturing organizations to manufacture and supply its product candidates; and OncoMed's dependence on its Chairman and Chief Executive Officer, its Executive Vice President, Research and Development, its Chief Medical Officer and other key executives. OncoMed undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to OncoMed's business in general, see OncoMed's Annual Report on Form 10-K for the fiscal year ended December 31, 2015, filed with the Securities and Exchange Commission (SEC) on March 10, 2016, and its other periodic reports filed with the SEC.

Michelle Corral
Senior Director, Investor Relations and Corporate Communications
OncoMed Pharmaceuticals
(650) 995-8373


OncoMed Pharmaceuticals, Inc. is a wholly-owned subsidiary of Mereo BioPharma Group plc.
Please visit our parent site for our Pipeline, Partnering Opportunities and Investors information.