Temsirolimus in Daily Use: Results of a Prospective Multicentre Noninterventional Study of Patients with Metastatic Kidney Cancer

BackgroundTemsirolimus (TEMSR) was approved for treating advanced renal cell carcinoma (RCC) in 2007. Based on the data from a single phase 3 trial, it is recommended explicitly as first-line therapy for patients with a poor clinical prognosis.ObjectiveThe aim of this prospective multicentre trial (STARTOR) was to examine the effectiveness of TEMSR in daily clinical practice with a broader indication in the treatment of metastatic RCC.Design, setting, and participantsMetastatic RCC patients treated with 25 mg of TEMSR weekly were submitted to a prospective systematic evaluation and follow-up in 87 German centres between January 2008 and October 2011 using standardised procedures.Outcome measurements and statistical analysisAll data were centrally analysed by an independent clinical research organisation.Results and limitationsThis interim analysis of the STARTOR study included 386 patients. The observed toxicity was tolerable, the median dose intensity was 91% (interquartile range: 79–100%), and the median treatment duration was 20.1 wk (95% confidence interval [CI], 17.0–23.3 wk). Clinical benefit was seen in 157 patients (40.7%); the median progression-free and overall survival were 4.9 mo (95% CI, 4.2–5.6) and 11.6 mo (95% CI, 9.3–13.9), respectively. The effectiveness of TEMSR did not differ significantly in relation to the patient's age, histologic RCC subtype, or line of treatment. The major limitations were the noninterventional study design, limited information about Memorial Sloan-Kettering Cancer Center risk factors and detailed toxicity, and the lack of central radiologic review.ConclusionsTEMSR is an effective and largely well-tolerated treatment alternative for metastatic RCC patients in daily clinical practice, irrespective of the patient's age, histologic RCC subtype, or line of treatment.