REDWOOD CITY, Calif., Aug. 22, 2013 (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 that the United States Patent and Trademark Office has issued U.S. Patent No. 8,507,442 to OncoMed for methods of treating cancer with its antibody vantictumab (OMP-18R5). Vantictumab targets and inhibits the Wnt pathway, which is believed to be an important CSC pathway. The patent expires in 2029. Vantictumab was originally identified at OncoMed from the HuCAL GOLD ® antibody library (MorphoSys AG) by binding to the Frizzled-7 receptor and was later determined by OncoMed to bind a novel epitope conserved across five different Frizzled receptors. Vantictumab has demonstrated broad anti-CSC and anti-tumor activity in patient-derived xenograft models and is currently being evaluated in a Phase 1 clinical trial where it has provided early signs of single-agent activity in patients with neuroendocrine tumors. The antibody is part of OncoMed's collaboration with Bayer Pharma AG. OncoMed previously received a U.S. patent claiming the composition of matter for vantictumab and has corresponding patents or pending patent applications covering vantictumab in fourteen additional countries and Europe. In addition, OncoMed has a robust patent portfolio of over 300 patents or pending patent applications, which includes multiple additional patent families related to vantictumab or its use. "OncoMed's new patent, together with its composition-of-matter patent, provides key patent coverage for vantictumab," said Paul Hastings, Chief Executive Officer of OncoMed. "The issuance of this patent also further validates the novelty of this promising antibody and the innovative nature of OncoMed's ongoing discovery programs, which have not only produced vantictumab, but also four other anti-CSC agents currently in 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 Frizzled 7, the antibody selectively targets five different Frizzled receptors. Vantictumab is currently being evaluated in a Phase 1 clinical trial. Vantictumab is part of OncoMed's collaboration with Bayer Pharma AG.