REDWOOD CITY, CA, USA I December 4, 2013 I OncoMed Pharmaceuticals, Inc. (OMED), a clinical-stage company developing novel therapeutics that target cancer stem cells (CSCs), or tumor-initiating cells, today announced that it has started a Phase 1b clinical trial of its first-in-class Wnt-pathway-targeting antibody vantictumab (OMP-18R5) in combination with nab-paclitaxel (Abraxane(R)) and gemcitabine in patients with Stage IV pancreatic cancer. This trial is the third of three Phase 1b trials for vantictumab initiated this year as part of OncoMed’s collaboration with Bayer Pharma AG.

The multi-center Phase 1b clinical trial is a dose escalation study that will evaluate safety of vantictumab in combination with Abraxane and gemcitabine and determine a recommended Phase 2 dose for this combination regimen. Key secondary and exploratory objectives include evaluation of the pharmacokinetics (PK) of vantictumab, as well as the pharmacodynamics (PD) and efficacy of this combination. Tumor tissue from patients will be used to explore predictive biomarker hypotheses related to the efficacy of vantictumab.

“Incidence of pancreatic cancer has been steadily rising. In spite of recent advancements, metastatic pancreatic cancer represents a significant unmet medical need and patients are in need of improved treatment options,” said Safi Shahda, M.D., Assistant Professor of Clinical Medicine at Indiana University in Indianapolis, IN, and the Principal Investigator who treated the first patient enrolled in this study. “By targeting cancer stem cells, vantictumab has the potential to augment the clinical benefit of standard chemotherapy in this disease setting. I am particularly excited by the inclusion of biomarker measures in this Phase 1b trial of vantictumab with Abraxane and gemcitabine, which will provide valuable information related to the drug’s mechanism of action.”

The other investigators and clinical sites to participate in the trial are: Jordan Berlin, M.D., Vanderbilt University, Nashville, TN; Steven Cohen, M.D., Fox Chase Cancer Center, Philadelphia, PA; Heinz-Josef Lenz, M.D., University of Southern California, Los Angeles, CA, and Wells Messersmith, M.D., University of Colorado Cancer Center, Aurora, CO.

Dr. Jakob Dupont, Chief Medical Officer of OncoMed, commented, “The Wnt signaling pathway is implicated to be central to cancer stem cells survival and potentially a key therapeutic target in pancreatic cancer. Our Wnt pathway targeting antibody, vantictumab, reveals impressive preclinical data efficacy data in combination with gemcitabine and Abraxane in OncoMed’s minimally passaged patient-derived pancreatic cancer models. We are pleased to have this Phase 1b trial underway and look forward to reporting data on the safety, efficacy and biomarker data of the vantictumab-Abraxane-gemcitabine combination in patients with late-stage pancreatic cancer.”

This is the third Phase 1b clinical study of vantictumab in combination with standard-of-care treatment initiated by OncoMed this year. Vantictumab plus docetaxel is being evaluated in non-small cell lung cancer and vantictumab combined paclitaxel is being studied in Her2-negative breast cancer. Interim results for the single-agent first-in-human Phase 1a trial for vantictumab in solid tumor patients were recently reported at the 2013 European Cancer Congress (ECC 2013) in Amsterdam, NL in September 2013. Results from the Phase 1a study showed that vantictumab is well tolerated with early evidence of single-agent activity. Additionally, clinical biomarker data from the Phase 1a trial indicating PD modulation of the Wnt pathway by vantictumab were presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston, MA in October 2013.

“This pancreatic cancer trial is the third vantictumab Phase 1b study initiated by OncoMed this year as part of the clinical development program that we are advancing in partnership with Bayer,” said Paul J. Hastings, Chairman and Chief Executive Officer of OncoMed. “The clinical data from these three trials will yield important clinical information about this novel anti-cancer stem cell agent in the key solid tumor indications of non-small cell lung, breast and pancreatic cancer and may also lead to an opt-in decision by Bayer to take vantictumab into late-stage randomized clinical trials.”

About Vantictumab (OMP-18R5)

Vantictumab is a first-in-class antibody that has shown broad anti-CSC and anti-tumor activity in patient-derived xenograft tumor models. Vantictumab inhibits a key signaling pathway in cancer, the Wnt pathway. Specifically, vantictumab selectively targets Frizzled receptors, which are activators of Wnt signaling. Although vantictumab was originally identified by binding to Frizzled7, the antibody selectively targets five different Frizzled receptors. OncoMed is currently completing a Phase 1a study of vantictumab in patients with advanced solid tumors. Preliminary data from this clinical trial were presented at the European Cancer Conference (ECC 2013) in September 2013 in Amsterdam, NL. Biomarker data for this Phase 1a trial were presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston, MA, in October 2013. Vantictumab is now being tested in combination with standard-of-care chemotherapy in three Phase 1b clinical trials in: 1) advanced NSCLC (vantictumab + docetaxel); 2) advanced HER2-negative breast cancer (vantictumab + paclitaxel); and 3) advanced pancreatic cancer (vantictumab + gemcitabine/Abraxane(R)). Vantictumab is part of OncoMed’s collaboration with Bayer Pharma AG.

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.

SOURCE: OncoMed Pharmaceuticals