OBJECTIVES: Metastatic renal cell carcinoma (mRCC) has a very high mortality rate with a 5 year survival of 5-15%. With the approval and use of a number of oral agents in the first line, treatment conditions for mRCC patients have significantly improved. Objective of this study was to evaluate the persistence in the first line treatment of mRCC patients in Germany. METHODS: The present study is based on the IMS LRx database containing 80% of all prescriptions reimbursed by the German statutory health insurance with an anonymized patient ID. The data base covers longitudinal information on patient level, such as age, gender, insurance company, region as well as prescriber specialty, date and medication on package level. Persistence was defined as the number of days from the date of the first prescription until the date of the last prescription plus the number of daily dosages prescribed. RESULTS: A total of 2799 patients starting first line treatment in mRCC between January 2010 and September 2010 were identified based on medication, co-medication and dosage. Median persistence in days was 84 for patients receiving Temsirolimus (T; n=384), 103 for Sorafenib (So; n=368), 117 for Pazopanib (P; n=66), 121 for Everolimus (E; n=468), 143 for Sunitinib (Su; n=1520) and 192 for Bevacizumab+Interferon (B, n=171). Approximately one quarter of patients were lost in the second month of treatment (T=39%; So=36%, P=35%; E=28%; Su=25%; B=21%). CONCLUSIONS: Persistence in first line treatment of mRCC is very low. Best persistence can be observed for Bevacizumab+Interferon which is the only intravenous treatment in this indication. Further research may be required to evaluate if the increased use of oral treatments has a negative impact on patient adherence and if adequate measures are required to improve this situation.