Phase III study of gemcitabine/oxaliplatin (GEMOX) with or without erlotinib in unresectable, metastatic biliary tract carcinoma.

Abstract

LBA4032 Background: Currently, there is no standard regimen for palliative chemotherapy in metastatic, unresectable biliary tract cancer (BTC). A phase II trial of erlotinib monotherapy showed a promising anti-tumor activity in BTC with tolerable toxicity. Additionally, gemcitabine + erlotinib demonstrated superior efficacy when compared to gemcitabine alone in pancreatic cancer. Hence, we conducted a phase III trial to compare between GEMOX vs GEMOX+erlotinib (Tarceva [T]) (GEMOX/T) as first-line chemotherapy in unresectable, metastatic BTC. Methods: Eligible patients were as follows: histologically confirmed adenocarcinoma of biliary tract (CCC), ampulla of vater (AOV) or gall bladder (GB); unresectable or metastatic; ECOG performance status of 0~2; adequate marrow, hepatic, renal and cardiac functions; no prior chemotherapy. The primary endpoint was progression free survival (PFS). The study regimen was gemcitabine 1,000mg/m2, oxaliplatin 100mg/m2, erlotinib 100mg qd daily q 2 weeks. Results: From February 2009 to August 2010, 268 pts were randomized, 133 patients to GEMOX arm and 135 patients to GEMOX/T arm. Patient characteristics: median age 61 yrs (range 30-82); male (63.4%); CCC (n=180, 67.2%), GB (n=82, 30.6%), and AOV (n=6, 2.2%). With a median follow-up of 13.9 months (range, 6.7 – 25.0), median PFS was 5.8 months (95% CI, 4.6 - 7.0) in GEMOX/T arm and 4.2 months (95% CI, 2.7 - 5.7) in GEMOX arm (P=0.080). In subgroup analysis (CCC, n=180), however, median PFS was significantly longer in GEMOX/T arm (5.9 months) when compared with GEMOX arm (3.0 months, P=0.049). The overall response rate was significantly higher in the GEMOX/T arm when compared with GEMOX arm. There was no significant difference in overall survival between the two arms (GEMOX/T: 9.5 months, 95% CI, 7.6 – 11.4; GEMOX: 9.5 months, 95% CI, 7.5 – 11.5; P=0.611). The EGFR mutation testing results in correlation to responsiveness to erlotinib will be presented at the meeting. Conclusions: This phase III represents the first multicenter, randomized trial to compare GEMOX vs GEMOX/T in unresectable, metastatic BTC. Although PFS was not prolonged in GEMOX/T, there was a significant benefit in terms of PFS in GEMOX/T arm for CCC patients.