OBJECTIVES: To identify cost and cost effectiveness of R-MCP (rituximab, mitoxantrone, chlorambucil, prednisolone) vs. MCP in NHL-patients from the perspective of a third party payer in Germany (statutory sickness fund). METHODS: Resource utilization data on 329 patients were collected in parallel to a RCT and analyzed for the treatment phase. In addition, an interim analysis of the subsequent observation period was conducted. Patients were treated before the DRG-system was introduced in Germany. Therefore, length of each hospitalisation was used as proxy for case-complexity and as criterion for assignment to one of 3 DRGxs relevant for NHL-patients. Several sensitivity analyses were performed to address different DRG-grouping criteria and discounting scenarios. RESULTS: Mean cost per treatment cycle was €2700 for R-MCP and €1900 for MCP (p<0.0001). Mean observation periods after end of initial treatment were 21.2 months for R-MCP and 17.6 months for MCP (p=0.02). Hospitalisations for adverse events (-32%), new chemotherapies (-33%), treatment of progressive disease (-55%) and other reasons (-39%) were reduced in the R-MCP arm. This resulted in mean, undiscounted cost per patient in the observation period of €4600 for R-MCP and €7700 for MCP (p=0.02). To adjust for the difference in length of the observation period overall monthly costs were calculated and amounted to €1230 for R-MCP and €1290 for MCP (p=0.67). Sensitivity analyses did not result in major changes. Clinically, R-MCP resulted in an objective response rate of 85.6% vs. 65.5% with MCP. After two years event free survival for R-MCP was 69% vs. 44% for MCP alone (p<0.001). CONCLUSION: Initially higher treatment costs of R-MCP were compensated by savings due to better efficacy. Combined with the clinical superiority of R-MCP, this regime is likely to prevail as the dominant treatment strategy compared to MCP alone at the final analysis.