Resident Physician Cleveland Clinic Foundation Orrville, OH, United States
Background: Clinical trials for immunotherapy-based regimens in metastatic renal cell carcinoma have extensive inclusion/exclusion criteria. It is not well-established whether these criteria are clinically meaningful and impact patient outcome. We investigated clinical outcomes in a real-world cohort of patients who would not have met criteria for inclusion on front-line mRCC trials.
Methods: Patients at Cleveland Clinic treated with ipilimumab/nivolumab and axitinib/pembrolizumab for front-line mRCC were identified and divided into clinical trial eligible (CTE) and clinical trial ineligible (CTI) cohorts based on key inclusion/exclusion criteria from their respective phase 3 trials (CheckMate 214 and KEYNOTE-426). Objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) were compared in CTE and CTI cohorts by Fisher’s exact test and log rank test.
Results: In total, 62 patients treated with axitinib/pembrolizumab and 103 treated with ipilimumab/nivolumab were identified. IMDC criteria were similar across CTE and CTI patients in both axitinib/pembrolizumab and ipilimumab/nivolumab cohorts.
In the axitinib/pembrolizumab cohort (n=62), 25 (40%) patients were CTI. Most common reasons for ineligibility were lab abnormalities (n=11), histology (n=10), and brain metastases (n=3). There was no significant difference in response rates (p=0.08). Median PFS was numerically longer in CTE patients (28 vs 12 months; p=0.07). OS was higher in the CTE patients (p=0.04).
In the ipilimumab/nivolumab cohort (n=103), 59 (57%) were CTI. Most common reasons for ineligibility were brain metastases (n=16), lab abnormalities (n=16), and histology (n=14). There was no significant difference in response rates (p=0.22). PFS (p=0.003) and OS (p < 0.0001) were higher in the CTE patients (Table 1).
Conclusions: Many real-world patients are ineligible for RCC clinical trials and have worse PFS and OS compared to trial-eligible patients. Additional treatment options are needed for these patients as well as strategies to include them in prospective trials. Additional data will be presented.
