OncoMed Announces Publication of Anti-RSPO Antibody Research in Cancer Research

REDWOOD CITY, Calif., Jan. 08, 2016 (GLOBE NEWSWIRE) — OncoMed Pharmaceuticals Inc. (NASDAQ:OMED), a clinical-stage company developing novel anti-cancer stem cell and immuno-oncology therapeutics, today announced the publication of a manuscript in Cancer Research describing OncoMed’s efforts to develop novel therapeutics against R-spondin (RSPO) targets and elucidating the link between expression of the RSPO cancer stem cell pathway and tumor growth.  OncoMed is currently conducting a Phase 1a/b clinical trial of its anti-RSPO3 (OMP-131R10) antibody.

The article “Therapeutic Targeting of Tumor-Derived R-Spondin Attenuates beta-Catenin Signaling and Tumorigenesis in Multiple Cancer Types” (released online December 30, 2015) describes the generation of neutralizing monoclonal antibodies against RSPO-1, -2 or -3 and the successful use of these antibodies to treat diverse types of patient-derived xenografts, including colon, ovarian, pancreas and lung tumors.  Of note, these anti-RSPO antibodies were effective in the tumor models regardless of whether the tumors overexpressed RSPO because of gene translocations or because of other tumor-intrinsic pathways.  OncoMed is utilizing biomarker assays to prospectively screen patients for RSPO gene expression as part of its Phase 1a/b clinical program.

Mechanistically, the paper establishes a functional link between RSPO expression and tumor growth.  Tumor-derived RSPO can activate beta-catenin, and antibody-mediated blocking of RSPO binding to its receptor potently inhibits tumor growth.  This anti-tumor activity is associated with the modulation of beta-catenin and cancer stem cell pathways.

“R-spondins are emerging as an important cancer target.  As key stimulators of beta-catenin activity in a variety of human tumor types, targeting the RSPO pathway may prove to be an effective approach to modulating this fundamental signaling axis,” said John Lewicki, Ph.D., OncoMed’s Chief Scientific Officer.  “Our first anti-RSPO candidate is being studied in Phase 1a/b clinical trials with a strong biomarker hypothesis and we expect to establish a single-agent dose and treat biomarker-positive patients this year.”

About Anti-RSPO3
OncoMed’s anti-RSPO3 (OMP-131R10) is the first drug in its class to target the R-spondin-LGR pathway, an important cancer stem cell pathway identified by OncoMed researchers.  The company’s ongoing Phase 1a/1b clinical trial is initially enrolling patients with advanced refractory solid tumors to assess the safety, pharmacokinetics, pharmacodynamics and initial evidence of efficacy of the anti-RSPO3 antibody. Once a single-agent dose has been identified, biomarker-selected patients will be enrolled in a Phase 1a expansion arm to evaluate possible anti-tumor activity.  In the Phase 1b portion of the trial, anti-RSPO3 will also be tested in second-line colorectal cancer patients in combination with chemotherapy.

In preclinical studies OncoMed’s anti-RSPO3 antibody demonstrated robust in vivo anti-tumor efficacy as a single agent and in combination with standard of care across a range of solid tumors, including colon, lung, ovarian, and pancreatic cancers, among others. The anti-RSPO3 antibody delayed tumor recurrence following termination of chemotherapy, and decreased the frequency of cancer stem cells.  Anti-RSPO3 antibody represents the third product candidate in the clinic that is part of OncoMed’s collaboration with Celgene.

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 product 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 has formed strategic alliances with Celgene Corporation, Bayer Pharma AG and GlaxoSmithKline (GSK).  OncoMed is advancing its wholly owned GITRL-Fc candidate and an undisclosed immuno-oncology target that is part of OncoMed’s collaboration with Celgene toward clinical trials in the 2016-2017 timeframe. 

Please see the company’s website at www.oncomed.com for additional information.

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 effectiveness of targeting R-spondins to modulate beta-catenin activity and treat cancer; and OncoMed’s ability to establish a single-agent dose and enroll biomarker-positive patients in its anti-RSPO3 clinical trial this year.  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 Chief Scientific Officer, 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, 2014, filed with the Securities and Exchange Commission (SEC) on March 12, 2015, OncoMed’s Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2015, filed with the SEC on May 7, 2015, OncoMed’s Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 2015, filed with the SEC on August 10, 2015, and OncoMed’s Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2015, filed with the SEC on November 5, 2015.


OncoMed Pharmaceuticals

Michelle Corral

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Shari Annes

Annes Associates


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