OMP-54F28 Is a First-in-Class WNT-Pathway-Targeting Decoy Receptor

REDWOOD CITY, CA, USA I January 13, 2014 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 multi-center Phase 1b clinical trial of its first-in-class Wnt-pathway-targeting decoy receptor OMP-54F28 (Fzd8-Fc) with nab-paclitaxel (Abraxane(R)) and gemcitabine in pancreatic cancer. This trial is the first of three Phase 1b trials for OMP-54F28 expected to begin patient enrollment in the next few months as part of OncoMed’s collaboration with Bayer Pharma AG. This study follows on the recent initiation of OncoMed’s Phase 1b program for the Wnt-pathway-targeting antibody vantictumab (OMP-18R5, Anti-Fzd7).

The Phase 1b clinical trial is a dose escalation study of OMP-54F28 in combination with nab-paclitaxel and gemcitabine in patients with first-line Stage IV pancreatic cancer. Primary objectives of the trial are to evaluate safety of this combination regimen and determine a recommended Phase 2 dose for OMP-54F28 in combination with nab-paclitaxel and gemcitabine. Key secondary and exploratory objectives include evaluation of the pharmacokinetics (PK) and pharmacodynamics (PD) of OMP-54F28, as well as the efficacy of this combination. Tumor tissue from patients will be used to explore predictive biomarker hypotheses related to the efficacy of OMP-54F28.

Colin Weekes, M.D. Ph.D., Assistant Professor at the University of Colorado, Aurora, CO, is the Principal Investigator who treated the first patient enrolled in this study. Dr. Weekes commented, “Metastatic pancreatic cancer is a devastating disease and these patients are in need of additional therapeutic options. OMP-54F28 has shown impressive combination efficacy with Abraxane and gemcitabine in preclinical models for pancreas cancer. We are looking forward to learning more about this novel investigational combination in pancreas cancer patients.”

Four additional investigators and clinical sites are expected to participate in this trial: Jordan Berlin, M.D., Vanderbilt University, Nashville, TN; Efrat Dotan, M.D., Fox Chase Cancer Center, Philadelphia, PA; Heinz-Josef Lenz, M.D., University of Southern California, Los Angeles, CA; and Bert O’Neil, M.D., Indiana University, Indianapolis, IN.

“OMP-54F28 combined with Abraxane and gemcitabine demonstrates potent and sustained anti-tumor activity as well as anti-CSC activity in preclinical patient-derived pancreas cancer xenograft models. We are eager to explore whether these findings can be translated into the clinic as we embark on this important step of evaluating safety, biomarkers, and efficacy of OMP-54F28 in combination with standard-of-care chemotherapy in patients with metastatic pancreatic cancer,” said Jakob Dupont, M.D., Chief Medical Officer of OncoMed.

This first Phase 1b study for OMP-54F28 will be followed shortly by two additional Phase 1b studies. Interim results for the single-agent, first-in-human Phase 1a trial for OMP-54F28 in solid tumor patients were recently presented at the 2013 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston. Results from the Phase 1a study showed that OMP-54F28 is well tolerated and modulates the Wnt pathway starting at low doses, as evidenced by PD biomarker analysis of hair follicles. OncoMed recently initiated Phase 1b studies for its other Wnt-pathway-targeting product candidate, vantictumab, in HER2-negative breast cancer, non-small cell lung cancer and pancreatic cancer.

“The initiation of the Phase 1b program for OMP-54F28, so quickly after starting three Phase 1b combination studies for vantictumab, brings us closer to our goal of having all six Phase 1b combination trials for our Wnt pathway program up and running in early 2014,” said Paul J. Hastings, OncoMed’s Chairman and Chief Executive Officer. “Data generated from these studies will serve to inform future Phase 2 trials and provide the basis for Bayer to exercise their option to license OMP-54F28 and vantictumab.”

About OMP-54F28 (Fzd8-Fc)

OMP-54F28 is a first-in-class fusion protein that has shown broad anti-CSC and anti-tumor activity in patient-derived xenograft tumor models. OMP-54F28 inhibits a key signaling pathway in cancer, the Wnt pathway. Specifically, OMP-54F28 consists of the extracellular ligand-binding domain of the Frizzled 8 receptor and the Fc domain of a human IgG1 antibody. OMP-54F28 selectively binds Wnt ligands, which are activators of Wnt signaling. OMP-54F28 is currently in Phase 1a in patients with refractory solid tumors. Data from the OMP-54F28 solid tumor trial were presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston, MA, in October 2013. OMP-54F28 is now being tested in combination with standard-of-care chemotherapy in a Phase 1b clinical trial in advanced pancreatic cancer (OMP-54F28 + gemcitabine/Abraxane(R)). Two additional Ph1b trials in distinct solid tumor indications are planned to initiate by early 2014. OMP-54F28 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