CHICAGO—Erlotinib, when added to gemcitabine + oxaliplatin chemotherapy, provided a significant benefit in terms of progression-free survival (PFS) in patients with histologically confirmed adenocarcinoma of the biliary tract (CCC), though it did not prolong overall PFS for biliary tract cancer (BTC), based on data results presented by Ho Yeong Lim, MD, from the Sungkyunkwan University School of Medicine, Seoul, Korea, and colleagues at the American Society of Clinical Oncology’s 2011 Annual Meeting.
Study investigators conducted a Phase 3, randomized, open study to compare gemcitabine + oxaliplatin (GEMOX) with GEMOX + erlotinib as first-line therapy in resectable, metastatic BTC. Eligible patients had histologically confirmed CCC, at the ampulla of vater (AOV) or gallbladder (GB); unresectable or metastatic disease, ECOG performance status 0–2; measureable lesion(s) per RECIST 1.0; adequate marrow, hepatic, renal, and cardiac functions; and no prior chemotherapy. The primary endpoint was PFS.
Patients received gemcitabine 1,000mg/m2 and oxaliplatin 100mg/m2 with or without erlotinib 100mg; all daily for 2 weeks. A total of 268 patients were randomized, 133 to the GEMOX arm and 135 to the GEMOX + erlotinib arm. Patient characteristics are as follows: media age 61 years (range 30–82); male (63.4%); CCC (n=180, 67.2%); AOV (n=6, 2.2%); and GB (n=82, 30.6%). Median duration of follow-up was 13.9 months (range, 6.7–25).
Results showed median PFS to be 5.8 [95% CI 4.6–7.0] months for the GEMOX + erlotinib arm compared with 4.2 [95% CI 2.7–5.7] months for the GEMOX arm; P=0.0796. In a subgroup analysis for patients with CCC, median PFS was significantly longer in the GEMOX + erlotinib arm (5.9 months) when compared with the GEMOX arm (3 months); P=0.0.495.
Overall response rate was significantly higher in the GEMOX + erlotinib arm compared with the GEMOX arm (34.4% vs. 17.8%). However, there was no significant difference in overall survival between the two arms (9.5 [95% CI 7.6–11.4] months and 9.5 [95% CI 7.5–11.5], respectively; P=0.611).
Dr. Lim concludes that though PFS was not prolonged by GEMOX + erlotinib therapy for BTC, there may be a benefit to PFS for the subgroup of CCC patients.