OncoMed Enrolls First Patient in Phase 1b Clinical Trial of its Anti-DLL4/VEGF Bispecific Antibody in Patients with Platinum-Resistant Ovarian Cancer

OncoMed Pharmaceuticals, Inc. (NASDAQ:OMED), a clinical-stage company focused on discovering and developing novel anti-cancer stem cell and immuno-oncology therapeutics, today announced it has enrolled and dosed the first patient in a Phase 1b clinical trial of its anti-DLL4/VEGF bispecific antibody (OMP-305B83) in combination with paclitaxel in patients with platinum-resistant ovarian cancer.  OncoMed’s anti-DLL4/VEGF bispecific antibody is designed to have anti-angiogenic, anti-cancer stem cell and immuno-modulatory activity.
The Phase 1b multicenter, open-label, dose-escalation and expansion trial is designed to assess the safety, preliminary efficacy, immunogenicity, pharmacokinetics and biomarker effects of the anti-DLL4/VEGF bispecific antibody plus paclitaxel.  OncoMed expects to enroll approximately 30 patients with platinum-resistant ovarian cancer (including fallopian tube or primary peritoneal cancers) who have previously received bevacizumab (Avastin^®, anti-VEGF) and/or have failed at least two prior therapies. The Phase 1b trial of anti-DLL4/VEGF antibody in patients with ovarian cancer is being conducted at five clinical sites in the United States.“There are few treatment options available to women whose ovarian cancer is resistant to platinum-based chemotherapy and have failed treatment with bevacizumab or two or more prior therapies,” said Robert Stagg, Pharm D., OncoMed’s Senior Vice President, Clinical Research and Development.  “We observed evidence of anti-tumor activity in these types of patients in our Phase 1a clinical trial, and we look forward to studying the potential impact of our anti-DLL4/VEGF bispecific combined with chemotherapy in this patient population.”In an ongoing Phase 1a dose escalation and expansion study of 51 patients with previously treated advanced solid tumors, OncoMed’s anti-DLL4/VEGF bispecific antibody was generally well tolerated with hypertension, headache and pulmonary hypertension being the most common drug related toxicities. Single-agent anti-tumor activity was observed.  Two of 46 evaluable patients had a partial response and 12 other patients had a reduction in tumor volume.  In the Phase 1a trial, five of eight evaluable patients with ovarian cancer had a reduction in tumor volume and remained on therapy for 129-357+ days.  Four of these five patients had previously received bevacizumab.¹About anti-DLL4/VEGF Bispecific Antibody (OMP-305B83)
OncoMed’s anti-DLL4/VEGF bispecific antibody is designed to inhibit the function of both DLL4 and VEGF and thereby induce potent anti-tumor responses while mitigating certain angiogenic-related toxicities.  It was developed utilizing OncoMed’s BiMAb^™ bispecific platform technology, which enables the design of bispecific antibodies comparable to traditional monoclonal antibodies but possessing dual target-binding specificity.  In preclinical studies OncoMed’s anti-DLL4/VEGF bispecific antibody demonstrated robust in vivo anti-tumor efficacy across a range of solid tumor xenografts, including colon, ovarian, lung and pancreatic cancers, among others.  Further, in preclinical studies dual inhibition of DLL4 and VEGF appears to exhibit synergistic anti-tumor activity at doses where blockade of either target alone elicited sub-optimal activity.OncoMed is currently conducting two Phase 1b clinical trials of its anti-DLL4/VEGF bispecific antibody in combination with standard of care chemotherapies: one in patients with metastatic colorectal cancer and a second in women with platinum-resistant ovarian cancer.  The anti-DLL4/VEGF bispecific antibody is part of OncoMed’s collaboration with Celgene Corporation.
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 internally discovered a broad pipeline of investigational drugs intended to address the fundamental biology driving cancer’s growth, recurrence and metastases.  Demcizumab (anti-DLL4, OMP-21M18), tarextumab (anti-Notch2/3, OMP-59R5), anti-DLL4/VEGF bispecific antibody (OMP-305B83), vantictumab (anti-FZD7, OMP-18R5), ipafricept (FZD8-Fc, OMP-54F28), anti-RSPO3 (OMP-131R10) and anti-TIGIT (OMP-313M32) are part of the company’s strategic alliances with Celgene Corporation, Bayer Pharma AG and GlaxoSmithKline (GSK).  OncoMed is independently developing brontictuzumab (anti-Notch1, OMP-52M51) and GITRL-Fc, as well as continuing to pursue new drug discovery research efforts.  For further information about OncoMed Pharmaceuticals, please see www.oncomed.com.¹Jimeno, et al; “A First-in-Man Phase 1a Study of the Bispecific Anti-DLL4/Anti-VEGF Antibody OMP-305B83 in Patients with Previously Treated Solid Tumors;” 28^th EORTC-NCI-AACR Molecular Targets and Cancer Symposium
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 potential impact of OncoMed’s anti-DLL4/VEGF antibody (OMP-305B83) with chemotherapy in the patient population that will be treated in the Phase1b trial in ovarian cancer; the number of patients who will be enrolled in the Phase1b trial in ovarian cancer; the anti-cancer stem cell, immunomodulatory, and anti-angiogenic activity of OMP-305B83; and the synergistic anti-tumor activity of dual inhibition of DLL4 and VEGF.  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; OncoMed’s ability to discover, develop and commercialize additional product candidates; and OncoMed’s dependence on its 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 filed with the U.S. Securities and Exchange Commission (SEC) on March 10, 2016, OncoMed’s Quarterly Report on Form 10-Q filed with the SEC on November 1, 2016, and OncoMed’s other current and periodic reports filed with the SEC.Contact:
Michelle Corral
Senior Director, Investor Relations and Corporate Communications
OncoMed Pharmaceuticals
(650) 995-8373