A Phase Ib/II Study Evaluating the Combination of Weekly Docetaxel and Cisplatin Together with Capecitabine and Bevacizumab in Patients with Advanced Esophago-Gastric Cancer

Introduction Current treatment options for advanced esophagogastric cancer (AEGC) are still unsatisfactory. The aim of this prospective phase Ib/II study was to evaluate the safety and efficacy of a novel regimen, AVDCX, consisting of weekly docetaxel and cisplatin together with capecitabine and bevacizumab, in AEGC. Methods Patients with AEGC received treatment with different dose levels of AVDCX (cisplatin and docetaxel 25-35 mg/m2, days 1,8, capecitabine 1,600 mg/m2 days 1-14, bevacizumab 7.5 mg/kg, day 1, Q:21 days). The study's primary objectives were to establish the recommended phase II doses of docetaxel and cisplatin in AVDCX (phase Ib part) and to determine the tumor response rate (phase II part). Results The study was closed early, after the accrual of 22 patients, due to accumulating toxicity-related deaths. The median age was 59 years and 77% of patients had gastric or gastroesophageal adenocarcinomas. Grade ≥3 adverse events were documented in 18 patients (82%), usually neutropenia (36%), fatigue (54%) or diarrhea (23%). There were three fatal toxicities (14%): mesenteric thromboembolism, gastric perforation and pancytopenic sepsis. The recommended phase II doses of cisplatin and docetaxel were determined to be 25 mg/m2 and 30 mg/m2, respectively. Twenty-one patients were evaluable for response: 12 (54%) had partial response (PR), 4 (18%) had stable disease (SD) and none had complete response (CR). Hence, the objective response rate (CR+PR) was 54% and the disease control rate (CR+PR+SD) was 72%. For the 17 patients treated at the MTD, the objective response rate was 41% and the disease control rate was 88%. The median overall survival (OS) for these patients was 13.9 months (range, 1.5-52.2 months) and the median progression-free survival was 7.6 months (range, 1.3-26.6 months). The 2-year OS rate reached 23.7%. Conclusions AVDCX was associated with a high rate of regimen related fatal adverse events and is not appropriate for further development in AEGC patients. Trial registration ClinicalTrials.gov NCT00845884.