A review of interventional clinical trials in renal cell carcinoma: a status report from the ClinicalTrials.gov WebSite

Introduction: The treatment of renal cell carcinoma (RCC) has undergone a major shift over the past 10 years and continues to evolve. The objective of this study was to assess the current landscape of clinical trials (CTs) in RCC to identify areas of strength and opportunities for improvement.

Materials and methods: ClinicalTrials.gov was queried using 17 prespecified search criteria. Only open, RCC-dedicated, interventional CTs in adult patients were included. Descriptive statistics and Fisher exact tests were used to compare features of CTs.

Results: The study cohort consisted of 169 trials. Phase II trials were the most common (67, 39.6%) and 52.7% (89) of CTs examined patients with stage IV disease. Only 26.6% (45) were randomized and 64.5% (109) were single-arm. Targeted therapies (TTs) were studied in 47.9% (81) of CTs overall and 71.1% (81 of 114) of the systemic therapy trials. Immunotherapies (ITs) were the next most common systemic therapy accounting for 5.9% (10) of trials. The primary end point of feasibility or biomarker analysis, progression-free survival, or overall survival was noted in 27.8%, 51.5%, and 2.1% of TT CTs (27, 50, 2 trials, respectively) and 42.9%, 35.7%, and 14.3% of IT CTs (6, 5, 2 trials respectively; P = .037). Biomarkers were assessed in 45% (76) of CTs overall and were more frequently examined in TT and IT CTs (53.6% [52/97] and 64.3% [9/14]) than in surgery and other CTs (22.2% [4/18] and 27.5% [11/40]; P = .002). Sponsorship differed according to treatment type (P = .003).

Conclusion: Clinical trials in RCC are largely nonrandomized, single-arm, with minimal focus on non-clear-cell RCC. Significant differences were noted in the primary end point, sponsorship, and biomarker assessment between treatment types.