Multicenter phase II trial to investigate safety and efficacy of gemcitabine combined with cetuximab as adjuvant therapy in pancreatic cancer (ATIP)

Abstract

BackgroundTo investigate whether addition of cetuximab to standard adjuvant chemotherapy with gemcitabine improves outcome in pancreatic cancer, specifically whether the rate of disease-free survival (DFS) at 18 months (primary end point) exceeds the previously reported 35% of gemcitabine alone. Patients and methodsProspective, open-label, multicenter, nonrandomized phase II study in 76 patients with R0- or R1-resected ductal adenocarcinoma of the pancreas included between October 2006 and November 2008. Gemcitabine and cetuximab were administered for 24 weeks. Secondary end points included overall survival (OS) and toxic effect. ResultsSeventy-three patients received cetuximab. Median DFS was 10.0 [95% confidence interval (CI) 8.9–13.6] months and the DFS rate at month 18 of 27.1% (16.7%–37.6%) was inferior to 35%. Median OS was 22.4 (18.2–27.9) months. Subgroup analyses revealed a nonsignificant increase in DFS for patients with versus without skin toxic effect ≥grade 2 (median 14.7 versus 8.3 months, P = 0.073) and wild-type versus mutated K-Ras (median 11.5 versus 9.3 months, P = 0.57). Grade 3/4 toxic effects included neutropenia (11.0%), thrombopenia (7%), skin toxic effect (7%) and allergic reactions (7%). ConclusionAddition of cetuximab to adjuvant gemcitabine does not seem to improve DFS or OS of unstratified pancreatic cancer patients. Trends for improved DFS in patients with wild-type K-Ras and skin toxic effect remain to be confirmed.