OncoMed Begins Patient Dosing In Phase 2 Clinical Trial Of Tarextumab In Small Cell Lung Cancer

OncoMed Pharmaceuticals, Inc.

, a clinical-stage company developing novel therapeutics that target cancer stem cells (CSCs), or tumor-initiating cells, announced that patient dosing has begun in the randomized, placebo-controlled Phase 2 portion of the company's "PINNACLE" clinical trial of its anti-Notch2/3 cancer stem cell antibody, tarextumab (OMP-59R5), for the treatment of small cell lung cancer (SCLC). Tarextumab is being studied in combination with chemotherapy in patients with previously untreated, extensive stage SCLC. The randomized Phase 2 trial will compare progression-free survival (PFS) outcomes for patients treated with tarextumab administered at 15 mg/kg every two weeks in combination with etoposide and cisplatin or carboplatin versus patients who receive chemotherapy alone. Additionally, PFS will be assessed using a predictive biomarker for high tumor Notch3 expression. OncoMed scientists have determined that high tumor Notch3 expression is estimated to occur in about 60 percent of small cell lung cancer patients. Secondary endpoints for the Phase 2 study include overall survival, overall response rate, pharmacokinetics, safety and other biomarkers. The PINNACLE study is being conducted at about 40 sites in the U.S. and is expected to enroll approximately 130 patients. "Small cell lung cancer is a devastating disease and patients are in need of new treatment options," said Jakob Dupont, M.D., OncoMed's Chief Medical Officer. "Based on the manageable safety profile and the early response data observed in the Phase 1b portion of the PINNACLE study, we are excited to advance tarextumab into the randomized Phase 2 portion of this clinical trial. As reported in September at the 2014 ESMO Congress, tarextumab has been well tolerated and does not appear to add significant toxicities to standard-of-care chemotherapies. Additionally, partial responses were observed in 13 of 16 evaluable patients." OncoMed has completed enrollment in the Phase 1b portion of the PINNACLE study, which was designed to establish a maximum-tolerated dose for tarextumab when administered in combination with etoposide and cisplatin or carboplatin. Phase 1b PINNACLE data in patients with small cell lung cancer was reported at the European Society of Medical Oncology (ESMO) Congress 2014 in September 2014. Tarextumab was well tolerated in combination with etoposide and cisplatin. Of sixteen patients evaluable for efficacy, thirteen achieved partial responses (81.3%) and the remaining three patients achieved stable disease for a clinical benefit rate of 100 percent. "We are driving all of our pipeline programs toward advanced clinical read-outs and partner opt-ins," said Paul J. Hastings, OncoMed's Chairman and Chief Executive Officer. "This is the second of four randomized Phase 2 programs expected to begin by late 2014 or early 2015. In addition to tarextumab in SCLC and pancreatic cancer, which are both now under way, we are very close to enrolling patients in randomized studies of our anti-DLL4 antibody, demcizumab, in pancreatic and non-small cell lung cancer. Our aim is to have multiple randomized Phase 2 data results between now and by the end of 2016."