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,

Docetaxel in the treatment of gastric cancer

Docetaxel is part of the standard chemotherapy in breast, non-small cell lung cancer and androgen-independent metastatic prostate cancer and has recently been approved for advanced gastric cancer. It demonstrated promising single-agent efficacy in gastric cancer and was therefore investigated in different combination regimens. The combination of docetaxel with 5-fluorouracil (5-FU), capecitabine, irinotecan or cisplatin demonstrated high efficacy. The triple combination of docetaxel/cisplatin and 5-FU (DCF) was investigated in randomized Phase II trials and a randomized Phase III study (TAX325). In TAX325, DCF demonstrated superiority in terms of time to tumor progression, response rate and survival against a cisplatin/5-FU combination. Docetaxel was therefore approved for advanced gastric cancer by the US FDA and the European Agency for the Evaluation of Medicinal Products and will evolve as an integral part of routine combination regimens against gastric cancer. This review will discuss and interpret the different Phase II and III trials of docetaxel in gastric cancer.