Purpose: Exatecan mesylate is a hexacyclic, water-soluble, topoisomerase-1 inhibitor. Exatecan has single-agent and combination activity with gemcitabine in advanced pancreatic cancer. A multicenter, randomized, phase III trial comparing exatecan plus gemcitabine versus gemcitabine alone in advanced pancreatic cancer was conducted.
Patients and methods: Eligibility criteria included Karnofsky performance status > or = 60%, locally advanced or metastatic pancreatic adenocarcinoma, and no prior chemotherapy. Radiation alone for locally advanced disease was permitted. Patients were randomly assigned on a 1:1 basis. For the exatecan plus gemcitabine arm, exatecan 2.0 mg/m2 and gemcitabine 1,000 mg/m2 were administered on days 1 and 8, every 3 weeks. Gemcitabine alone was dosed at 1,000 mg/m2 up to 7 weeks in the first cycle, then once a week for the first 3 weeks of a 4-week cycle. Tumor assessment was performed every 6 weeks. The primary end point was overall survival. An intent-to-treat analysis was used.
Results: From August 2001 to January 2003, 349 patients were randomly assigned, 175 to exatecan plus gemcitabine and 174 to gemcitabine alone. Twenty-four patients (6.9%) were not treated. The median survival time was 6.7 months for exatecan plus gemcitabine and 6.2 months for gemcitabine alone (P = .52). One complete response (CR; < 1%) and 11 partial responses (PRs; 6.3%) were observed in the exatecan plus gemcitabine treatment group, and one CR (< 1%) and eight PRs (4.6%) were observed in the gemcitabine-alone group. Grade 3 and 4 toxicities were higher for the exatecan plus gemcitabine arm versus the gemcitabine alone arm; neutropenia (30% v 15%) and thrombocytopenia (15% v 4%).
Conclusion: Exatecan plus gemcitabine was not superior to gemcitabine alone with respect to overall survival in the first-line treatment of advanced pancreatic cancer.