Randomised phase II trial to investigate catumaxomab (anti-EpCAM × anti-CD3) for treatment of peritoneal carcinomatosis in patients with gastric cancer.

BACKGROUND: Peritoneal carcinomatosis (PC) represents an unfavourable prognostic factor for patients with gastric cancer (GC). Intraperitoneal treatment with the bispecific and trifunctional antibody catumaxomab (EpCAM, CD3), in addition to systemic chemotherapy, could improve elimination of PC. METHODS: This prospective, randomised, phase II study investigated the efficacy of catumaxomab followed by chemotherapy (arm A, 5-fluorouracil, leucovorin, oxaliplatin, docetaxel, FLOT) or FLOT alone (arm B) in patients with GC and PC. Primary endpoint was the rate of macroscopic complete remission (mCR) of PC at the time of second diagnostic laparoscopy/laparotomy prior to optional surgery. RESULTS: Median follow-up was 52 months. Out of 35 patients screened, 15 were allocated to arm A and 16 to arm B. mCR rate was 27% in arm A and 19% in arm B (p = 0.69). Severe side effects associated with catumaxomab were nausea, infection, abdominal pain, and elevated liver enzymes. Median progression-free (6.7 vs. 5.4 months, p = 0.71) and overall survival (13.2 vs. 13.0 months, p = 0.97) were not significantly different in both treatment arms. CONCLUSIONS: Addition of catumaxomab to systemic chemotherapy was feasible and tolerable in advanced GC. Although the primary endpoint could not be demonstrated, results are promising for future investigations integrating intraperitoneal immunotherapy into a multimodal treatment strategy.

Perioperative chemotherapy with or without epidermal growth factor receptor blockade in unselected patients with locally advanced oesophagogastric adenocarcinoma: Randomized phase II study with advanced biomarker program of the German Cancer Society (AIO/CAO STO-0801).

BACKGROUND: Perioperative chemotherapy significantly improves survival in patients with locally advanced oesophagogastric cancer (EGC). However, as approximately 60% of patients will die from their disease, new therapeutic agents such as molecular-targeted drugs are needed. PATIENTS AND METHODS: To evaluate the role of panitumumab with perioperative chemotherapy, previously untreated patients with locally advanced EGC received, in an open-label randomised phase II study (NEOPECX), standard epirubicin, cisplatin, capecitabine (ECX) chemotherapy with or without panitumumab. The primary end-point was the histological response rate after neoadjuvant therapy. The expression status and gene copy number of EGFR, HER2, and MET were determined by immunohistochemistry and fluorescence in situ hybridization (FISH). Plasma samples were collected before the first cycle of neoadjuvant chemotherapy. RESULTS: Overall, 160 patients (80 versus 80) were eligible. The majority (82% versus 80%) showed lymph node involvement. Rate of R0-resection, percentage of patients with downstaging to ypT0-2 at pathohistological evaluation, and rate of major histological response was equal in both arms. Toxicity was increased by panitumumab with regard to thromboembolic events and skin toxicity. Patients with tumour EGFR, HER2 or MET expression had shorter progression-free and overall survival. FISH positivity for these markers was associated with shorter survival independent of therapy. High levels of soluble EGFR in particular predicted poor survival in the panitumumab arm. CONCLUSION: The addition of panitumumab to ECX did not improve downstaging of locally advanced EGC. Low plasma levels of pathway-associated proteins such as sEGFR may identify a group of patients that benefit from EGFR-directed therapy. CLINICALTRIALS.GOV: NCT01234324.

Effects of azathioprine and its metabolites on repair mechanisms of the intestinal epithelium in vitro.

Erosions and ulcerations of the intestinal epithelium are hallmarks of inflammatory bowel diseases (IBD). Intestinal epithelial cell migration (restitution) and proliferation are pivotal mechanisms for healing of epithelial defects after mucosal injury. In addition, the rate of apoptosis of epithelial cells may modulate intestinal wound healing. The purine antagonists azathioprine (AZA) and 6-mercaptopurine (6-MP) are widely used drugs in the treatment of IBD. In the present study, the hitherto unknown effects of AZA as well as its metabolites 6-MP and 6-thioguanine (6-TG) on repair mechanisms and apoptosis of intestinal epithelia were analysed. Intestinal epithelial cell lines (human Caco-2, T-84 and HT-29 cells, rat IEC-6 cells) were incubated with AZA, 6-MP or 6-TG for 24 h (final concentrations 0.1-10 microM). Migration of Caco-2 and IEC-6 cells was analysed by in vitro restitution assays. Caco-2 and IEC-6 cell proliferation was evaluated by measurement of [3H]thymidine incorporation into DNA. Apoptosis of Caco-2, T-84, HT-29 and IEC-6 cells was assessed by histone ELISA, 4'6'diamidino-2'phenylindole-dihydrochloride staining as well as flow cytometric analysis of Annexin V/propidium iodide (PI)-stained cells. Cell cycle progression was evaluated by PI staining and flow cytometry. Epithelial restitution was not significantly affected by any of the substances tested. However, proliferation of intestinal epithelial cells was inhibited in a dose-dependent manner (maximal effect 92%) by AZA, 6-MP as well as 6-TG. In HT-29 cells, purine antagonist-effected inhibition of cell proliferation was explained by a cell cycle arrest in the G2 phase. In contrast, AZA, 6-MP and 6-TG induced no cell cycle arrest in Caco-2, T-84 and IEC-6 cells. AZA, 6-MP as well as 6-TG induced apoptosis in the non-transformed IEC-6 cell line but not in human Caco-2, T-84 and HT-29 cells. In summary, AZA and its metabolites exert no significant effect on intestinal epithelial restitution. However, they profoundly inhibit intestinal epithelial cell growth via various mechanisms: they cause a G2 cell cycle arrest in HT-29 cells, induce apoptosis in IEC-6 cells and dose-dependently inhibit intestinal epithelial proliferation.