OncoMed Pharmaceuticals Presents Data From the Phase 1b Portion of the ALPINE Clinical Study of OMP-59R5 in Pancreatic Cancer at the 2014 Gastrointestinal Cancers Symposium

SAN FRANCISCO, Jan. 17, 2014 (GLOBE NEWSWIRE) -- OncoMed Pharmaceuticals, Inc. (Nasdaq:OMED), a clinical-stage company developing novel therapeutics that target cancer stem cells (CSCs), or tumor-initiating cells, today announced the first scientific presentation of results from the Phase 1b portion of its ongoing ALPINE (Antibody therapy in first-Line Pancreatic cancer Investigating anti-Notch Efficacy and safety) Phase 1b/2 clinical study of OMP-59R5 (anti-Notch 2/3) in patients with advanced pancreatic cancer. OMP-59R5 is part of OncoMed's collaboration with GlaxoSmithKline (GSK). These data were presented in a poster by Eileen M. O'Reilly, M.D., of Memorial Sloan-Kettering Cancer Center at the 2014 Gastrointestinal Cancers Symposium being held in San Francisco, California.  

"Pancreatic cancer has proven to be among the most challenging malignancies to treat," said Dr. O'Reilly. "The combination of OMP-59R5 with Abraxane and gemcitabine has been well tolerated and demonstrated positive signals of anti-cancer activity. We look forward to participating in the Phase 2 portion of the study."

Two cohorts of patients in the dose-escalating study received OMP-59R5 in combination with gemcitabine, with remaining cohorts receiving OMP-59R5 in combination with gemcitabine and Abraxane^® (nab-paclitaxel). OMP-59R5 administered in combination with standard-of-care was well tolerated, with no dose-limiting toxicities observed up to 12.5 mg/kg. Adverse events, most commonly diarrhea, fatigue and nausea, were typically Grade 1 or 2, and easily managed with supportive care. The combination with gemcitabine and Abraxane did not significantly alter pharmacokinetics (PK) of OMP-59R5, and pharmacodynamic (PD) analyses demonstrated on-target activity against the Notch cancer stem cell pathway. Following the data cutoff point, dose escalation proceeded to 15 mg/kg and enrollment in the ALPINE study is ongoing.

Twenty-one patients were evaluable for radiographic response. Thirteen of these 21 patients were treated with gemcitabine, Abraxane and OMP-59R5. Six of these thirteen patients (46%) treated with the three-drug combination achieved a RECIST partial response (PR) and an additional three patients achieved stable disease, for an overall disease control rate of 10 of 13 (77%). CA19-9 tumor blood marker values decreased by ≥ 50% from baseline among 10 of 13 (77%) patients in the OMP-59R5/gemcitabine/Abraxane cohorts. 

"These are the first clinical data from our Phase 1b ALPINE study to be presented in a scientific forum and we are pleased that the combination of OMP-59R5 with standard-of-care gemcitabine and Abraxane has been well tolerated," said Jakob Dupont, M.D., OncoMed's Chief Medical Officer. "Additionally, the early signs of potential efficacy in patients with metastatic pancreatic cancer are encouraging and we anticipate advancing OMP-59R5 into the randomized Phase 2 portion of the ALPINE study in the second quarter of 2014."

Data from the ongoing Phase 1b ALPINE study were presented in a poster titled: Phase 1b of anti-cancer stem cell antibody OMP-59R5 (anti-Notch2/3) in combination with nab-Paclitaxel and gemcitabine (Nab-P+Gem) in patients (pts) with untreated metastatic pancreatic cancer (mPC) (Abstract #220; Poster Board A49). 

Paul J. Hastings, Chairman and Chief Executive Officer of OncoMed, commented, "We are pleased with the steady progress being made across our clinical-stage portfolio, including the efficient advancement of our OMP-59R5 program in pancreatic and small-cell lung cancer. With more than a dozen studies across five distinct anti-cancer stem cell therapeutics actively enrolling patients, we can look forward to reporting additional data and advancing multiple anti-CSC products into new clinical studies in the months to come."

About OMP-59R5

OMP-59R5 is a fully human monoclonal antibody that targets the Notch2 and Notch3 receptors. Initially discovered by screening a phage display library against the Notch2 receptor, the antibody binds to a conserved epitope on Notch2 and Notch3. Preclinical studies have suggested that OMP-59R5 exhibits two mechanisms of action: (1) by downregulating Notch pathway signaling, OMP-59R5 appears to have anti-CSC effects, and (2) OMP-59R5 affects pericytes, impacting stromal and tumor microenvironment. The program is currently in two Phase 1b/2 proof-of-concept trials: 1) the "ALPINE" trial (Antibody therapy in first-Line Pancreatic cancer Investigating anti-Notch Efficacy and safety) is testing OMP-59R5 with gemcitabine and Abraxane^® in first-line advanced pancreatic cancer patients; and 2) the "PINNACLE" trial (Phase 1b/2 INvestigation of anti-Notch Antibody therapy with Cisplatin and etoposide in small cell Lung carcinoma Efficacy and safety), is testing OMP-59R5 in combination with cisplatin and etoposide in first-line extensive stage SCLC patients. OMP-59R5 is part of OncoMed's collaboration with GlaxoSmithKline (GSK). Data from the Phase 1b portion of the ALPINE study were presented in January 2014 at the Gastrointestinal Cancers Symposium held in San Francisco, CA. GSK has an option to obtain an exclusive license to OMP-59R5 during certain time periods through completion of the proof-of-concept Phase 2 trials. 

About Cancer Stem Cells

Cancer stem cells, or CSCs, are the subpopulation of cells in a tumor responsible for driving growth and metastasis of the tumor. CSCs, also known as tumor-initiating cells, exhibit certain properties which include the capacity to divide and give rise to new CSCs via a process called self-renewal and the capacity to differentiate or change into the other cells that form the bulk of the tumor. Common cancer drugs target bulk tumor cells but have limited impact on CSCs, thereby providing a path for recurrence of the tumor. OncoMed's product candidates target CSCs by blocking self-renewal and driving differentiation of CSCs toward a non-tumorigenic state, and also impact bulk tumor cells. OncoMed believes its product candidates are distinct from the current generations of chemotherapies and targeted therapies, and have the potential to significantly impact cancer treatment and the clinical outcome of patients with cancer.

About OncoMed Pharmaceuticals

OncoMed Pharmaceuticals is a clinical-stage company focused on discovering and developing novel therapeutics targeting cancer stem cells. OncoMed has five anti-cancer product candidates in clinical development, including demcizumab (Anti-DLL4, OMP-21M18), OMP-59R5 (Anti-Notch2/3), OMP-52M51 (Anti-Notch1), vantictumab (Anti-Fzd7, OMP-18R5), and OMP-54F28 (Fzd8-Fc), which target key cancer stem cell signaling pathways including Notch and Wnt.  OncoMed has two other antibodies in preclinical development, Anti-DLL4/Anti-VEGF bispecific and Anti-RSPO3, with Investigational New Drug filings planned for as early as 2014. OncoMed is also pursuing discovery of additional novel anti-CSC product candidates. OncoMed has formed strategic alliances with Celgene Corporation, Bayer Pharma AG and GlaxoSmithKline (GSK). Additional information can be found at the company's website: www.oncomed.com.

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 success of Phase 1b clinical trials for OMP-59R5 and a favorable safety profile for OMP-59R5; the successful advancement of OMP-59R5 to the Phase 2 portion of ALPINE; the potential of OncoMed's product candidates to significantly impact cancer treatment and the clinical outcome of patients with cancer, including the potential of OMP-59R5 to improve patient outcomes in pancreatic cancer in particular; the timing of clinical trials for OncoMed's product candidates, including advancement of OMP-59R5; and the timing of Investigational New Drug filings for OncoMed's product candidates, including Anti-DLL4/Anti-VEGF bispecific and Anti-RSPO3.  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; the risks and uncertainties of the regulatory approval process; OncoMed's dependence on its collaboration partners, including GSK, Bayer and Celgene, for the funding of its partnered programs; OncoMed's ability to raise capital to support the development of its unpartnered programs; OncoMed's dependence on the development and marketing efforts of its partners for the commercial success of its partnered product candidates; 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; OncoMed's ability to validate, develop and obtain regulatory approval for companion diagnostics; OncoMed's ability to achieve market acceptance and commercial success of its product candidates once regulatory approval is achieved; OncoMed's ability to discover, develop and commercialize additional product candidates; the ability of competitors to discover, develop or commercialize competing products more quickly or more successfully; OncoMed's dependence on its Chairman and Chief Executive Officer, its Chief Scientific Officer, its Chief Medical Officer and other key executives; risk of third party claims alleging infringement of patents and proprietary rights or seeking to invalidate OncoMed's patents or proprietary rights; and the ability of OncoMed's proprietary rights to protect its technologies and product candidates. 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 Prospectus filed with the Securities and Exchange Commission on July 18, 2013 and OncoMed's Quarterly Report on Form 10-Q for the fiscal quarter ended September 30,2013, filed with the Securities and Exchange Commission on November 13, 2013.

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