Abstract OBJECTIVE: Advanced biliary tract cancer is associated with a poor prognosis due to wide resistance to chemotherapeutic agents. This phase II clinical trial was conducted to determine the safety and efficacy of weekly gemcitabine and liposomal paclitaxel (Genexol-PM®) in patients with unrectable or metastatic biliary cancer. METHODS: The eligibility criteria were patients 1) with pathologically proven unresectable or metastatic biliary cancer, 2) with an ECOG performance status 0 to 2, 3) aged more than 18, 4) with measurable lesions, 5) with adequate hematologic, renal and liver functions, and 6) who provided written informed consent. Each treatment cycle was consisted of gemcitabine 1000 mg/m*2 and liposomal paclitaxel 100 mg/m*2 on days 1, 8 followed by rest perioid of 14 days. It was repeated until the appearance of disease progression or unacceptable toxicity up to maximal 9 cycles. The primary end point of this study was reponse rate, and secondary end points included toxicity, progression free survival and overall survival. RESULTS: Thirty five patients were enrolled; median age was 63 years; male (n=30) and female (n-10). The median number of cycles administered was 3.5 (range, 1-10). Thirty patients were assessable for efficacy. Nine partial responses and 16 stable diseases were confirmed. Giving an overall response rate was 35.6% and disease control rate was 55.6% in per-protocol population. Median overall survival was 12.3 months (95% CI: 5.79-18.74) and median progression free survival was 4.07 months(95% CI: 3.12-5.01). The most frequent adverse events (AE) of all grades were anemia and neutropenia (n=17) followed by leucopenia (13). Grade 3/4 hematologic AEs: anemia (n=6), neutropenia (n=11), thrombocytopenia (n=1). Grade 3/4 non-hematologic AEs: elevated liver function tests (n=3), hyperbilirubinemia (n=1) hyponatremia (n=1). CONCLUSION: Weekly gemcitabine combined with liposomal paclitaxel appears to be effective against advanced biliary cancers. Further randomized trials are needed to confirm this finding. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3705. doi:1538-7445.AM2012-3705