Everolimus vs. temsirolimus for advanced renal cell carcinoma: use and use of resources in the US Oncology Network.

BACKGROUND: The National Comprehensive Cancer Network (NCCN) guidelines suggest the use of inhibitors of mammalian target of rapamycin (mTOR), such as temsirolimus and everolimus, as first- and second-line therapy, respectively, for advanced or metastatic renal cell carcinoma (mRCC). However, adherence to this recommendation in clinical practice and the use of these 2 agents in mRCC is unknown. PATIENTS AND METHODS: We determined the prescribing patterns of temsirolimus and everolimus in a retrospective longitudinal cohort study of patients with mRCC receiving clinical care within The US Oncology Network. Outpatient health care use in patients with mRCC was derived for the categories of laboratory visits, acute care visits, minor procedures, radiation therapy, drug/medication use, and other services. RESULTS: Among 462 patients with mRCC, 144 (31%) were treated with everolimus and 318 (69%) were treated with temsirolimus. The use of temsirolimus vs. everolimus as first-, second-, and third-line therapy was 50.7% vs. 16.7%, 30.1% vs. 42.1%, and 19.3% vs. 83.2%, respectively. Despite similarities in disease stage and demographic features, compared with temsirolimus, everolimus use was independently associated with lower use of outpatient health care resources, regardless of the line of therapy. CONCLUSION: Notwithstanding the potential limitation that this was an observational retrospective study, our results indicate that everolimus results in substantial savings in the use of resources relative to temsirolimus. In a large geographically dispersed network of community-based oncology practices, both of these agents are used frequently outside of NCCN guidelines. A direct comparison of the efficacy and costs of everolimus vs. temsirolimus for mRCC is warranted.