OBJECTIVES: To evaluate the efficacy and safety of weekly administration of gemcitabine treatment in chemotherapy-naïve patients with advanced biliary tract and gallbladder cancer. PATIENTS AND METHODS: Gemcitabine at a dose of 800 mg/m2 was administered weekly as a 30-min infusion to patients with previously operated, histologically confirmed, metastatic, or unresectable locally advanced cholangiocarcinoma. Treatment was continued until unacceptable toxicity or disease progression. RESULTS: A total of 30 patients (median age 66 years; range 54-72 years) were included in the study. A median of 14 (range, 4-33) weekly doses was administered. Out of 30 patients evaluable for response, nine partial responses were observed (30.0%), while a further 11 patients demonstrated stable disease (36.7%). The median time to disease progression was 7 months (range, 5-34). Overall response rate was superior in patients with cancer of the gallbladder (ORR = 35.7%) compared with those patients with biliary duct cancer (ORR = 27.3%). This correlated to a significantly longer time to progression of 6.4 months (95% confidence interval (CI), 5.6-7.1 months) versus 3.6 months (95% CI, 2.9-4.3 months; p = 0.03) and a significantly better overall survival of 17.1 months (95% CI, 15.8-18.5 months) versus 11.4 months (95% CI, 10.2-12.6 months, p = 0.021). Toxicities were generally mild with only one case of grade 3 neutropenia. There were no cases of febrile neutropenia and no treatment-related deaths. CONCLUSIONS: Weekly administration of gemcitabine provides a safe, well-tolerated, and effective treatment for chemotherapy naïve patients with advanced cholangiocarcinoma, particularly with a gallbladder origin.