S-TRAC trial: Sensitivity analyses of disease-free survival (DFS).

Abstract

633 Background: DFS has been frequently used as endpoint in the adjuvant setting and was the primary basis of approval for adjuvant cancer therapies. In S-TRAC, adjuvant sunitinib demonstrated a significant improvement of DFS vs. placebo in patients with locoregional renal cell carcinoma (RCC) based on blinded independent central review. DFS was defined as time from randomization until recurrence or death from any cause or second cancer. In the absence of a standard definition of DFS in RCC, multiple sensitivity analyses were performed to confirm the robustness of the DFS results from S-TRAC. Methods: Two analyses considered the time to recurrence including and excluding RCC specific deaths and contralateral kidney recurrence. Additional analyses used the same event and censoring rules as the primary analysis but considered earliest dates of relapse for equivocal new lesions later determined to be unequivocal -to align with RECIST 1.1 criteria for new lesions- and some alternative dates for secondary malignancies. Other sensitivity analyses evaluating alternative event and censoring rules as well as the imbalance in censoring in the first year in the primary analysis will also be presented. Results: The HR from select sensitivity analyses are presented in the Table. Conclusions: Results of sensitivity analyses with alternative definitions of DFS in S-TRAC demonstrated the robustness of the primary DFS analysis, with consistent HRs (0.76-0.81) favoring sunitinib. Clinical trial information: NCT00375674. [Table: see text]