Background: The new pyrimidine antimetabolite Gemcitabine has shown preclinical efficacy in a number of solid tumour lines and acceptable toxicity in phase I trials. As part of an ongoing effort to identify active new agents in small cell lung cancer, the NCIC Clinical Trials Group studied Gemcitabine in previously untreated patients with extensive disease.
Patients and methods: Twenty-nine newly diagnosed patients with untreated extensive small cell lung cancer and at least one bidimensionally measurable site received Gemcitabine as a 30 minute intravenous infusion weekly x 3 every 4 weeks. The starting dose was 1000 mg/m2/week in the first 17 patients and 1250 mg/m2/week in the remainder. Patients were reevaluated for response every 4 weeks. Those failing to respond after 2 cycles of therapy were to be offered standard chemotherapy.
Results: Of the 29 patients entered, all were evaluable for toxicity and 26 for response. One complete and 6 partial responses were seen giving a response rate of 27% (95% CI: 11%-47%). Median response duration was 12.5 weeks and the median survival of the entire population was 12 months. Toxic effects were mild to moderate: in particular serious myelosuppression was uncommon.
Conclusions: Gemcitabine is active in previously untreated small cell lung cancer in doses which produce little toxicity. Combination studies of Gemcitabine with other agents active in this disease are warranted.