Eligibility Criteria and Endpoints in Metastatic Renal Cell Carcinoma Trials

Treatments for metastatic renal cell carcinoma (mRCC) are often compared across trials, but trial eligibility criteria and endpoints differ. In an effort to better align trials, the Definition for the Assessment of Time to event Endpoints in CANcer trials (DATECAN) project published recommendations in 2015 to be used in mRCC clinical trial design. We analyzed mRCC trial criteria to determine if DATECAN's recommendations were followed.

We compared eligibility criteria across 29 phase 3 mRCC trials conducted between 2003 and 2019. We then evaluated endpoints used in 10 phase 3 trials activated between 2015 and 2019 to determine their compliance with DATECAN's recommendations.

Among the 29 trials, performance status, renal function, and disease characteristics differed in terms of requirements and measures used. In terms of endpoints, the 10 trials did not entirely follow DATECAN's recommendations. In total, 7/10 trials' primary endpoint was progression-free survival (PFS) as recommended; 4/9 trials used PFS as an endpoint but did not publish their definition of PFS, and the 5 that did, included "death from any cause" instead of DATECAN's recommendation of "death from kidney cancer."

Key eligibility criteria were somewhat inconsistent across the phase 3 mRCC trials studied. Endpoints in the newer trials did not align with DATECAN's recommendations. Not only is greater standardization needed to facilitate meta-analyses and cross-trial comparisons, but as evident from lack of adherence to DATECAN's recommendations, greater promotion and adoption of recommendations are needed to better harmonize trial design.