Peritoneal Carcinomatosis Immunotherapy With The Trifunctional Anti-Epcam X Anti-Cd3 Antibody Catumaxomab In Patients With Colon, Gastric, Or Pancreatic Cancer: Long-Term Results After A 2-Year Follow-Up

3033 Background: Peritoneal carcinomatosis (PC) from gastrointestinal (GI) cancer is associated with a poor outcome. The trifunctional antibody catumaxomab may induce remission by redirecting T-lymphocytes and Fcγ-receptor I/III positive accessory cells to tumor cells. The aim of this study was to investigate the treatment of PC with intraperitoneal catumaxomab. Methods: Patients with epithelial cell adhesion molecule (EpCAM)-positive PC from GI cancer were enrolled in a multicenter phase I study and received four sequential intraperitoneal catumaxomab infusions on days 0, 3, 7, and 10 at increasing doses. Results: Twenty-four patients were enrolled. The maximum tolerated dose (MTD) was reached at 10, 20, 50, and 200 μg on days 0, 3, 7, and 10, respectively. The most common drug-related adverse events at the MTD were fever, vomiting, abdominal pain, skin toxicity, and nausea. Eleven of 17 evaluable patients (65%) were progression-free at final examination: one patient had a complete response and three pat...