Open-Label, Single-Arm Phase II Study of Pembrolizumab Monotherapy as First-Line Therapy in Patients With Advanced Clear Cell Renal Cell Carcinoma.

PURPOSE: Pembrolizumab, a programmed death 1 inhibitor, demonstrated promising single-agent activity in untreated patients with various cancer types. The phase II KEYNOTE-427 study evaluated efficacy and safety of single-agent pembrolizumab in treatment-naive patients with advanced clear cell renal cell carcinoma (ccRCC; cohort A) and advanced non-ccRCC (cohort B). Results of cohort A are reported. METHODS: In this open-label, single-arm phase II study, patients with advanced ccRCC received pembrolizumab 200 mg every 3 weeks for ≤ 24 months. The primary end point was objective response rate by RECIST, version 1.1. RESULTS: In the total population (N = 110), median time from enrollment to data cutoff was 35.9 (range, 29.5-40.3) months. Objective response rate was 36.4% with four (3.6%) complete responses and 36 (32.7%) partial responses; disease control rate was 58.2% (95% CI, 48.4 to 67.5). Most patients (68.2%) had a decrease in target lesions, including 30.9% with a reduction ≥ 60%. Median duration of response was 18.9 (range, 2.3-37.6+) months; 64.1% of responders had a response ≥ 12 months (Kaplan-Meier). Median progression-free survival was 7.1 months (95% CI, 5.6 to 11.0). Median overall survival was not reached; 12-month and 24-month overall survival rates were 88.2% and 70.8%, respectively. Durable responses were observed across all International Metastatic RCC Database Consortium categories. Grade 3-5 treatment-related adverse events were reported in 30.0% of patients, of which colitis and diarrhea were most frequent. CONCLUSION: Single-agent pembrolizumab showed promising antitumor activity as a first-line treatment in patients with advanced ccRCC, with durable responses across International Metastatic RCC Database Consortium categories. Safety and tolerability profile of pembrolizumab monotherapy was comparable to what has been previously described in other tumor types.

Safety and Efficacy of Nivolumab in Patients With Advanced Non-Clear Cell Renal Cell Carcinoma: Results From the Phase IIIb/IV CheckMate 374 Study.

BACKGROUND: The open-label phase IIIb/IV CheckMate 374 study (NCT02596035) was conducted to validate the safety and efficacy of flat-dose nivolumab 240 mg every 2 weeks (Q2W) in previously treated advanced/metastatic renal cell carcinoma. Three cohorts included patients with predominantly clear cell histology, non-clear cell histologies, or brain metastases. We report safety and efficacy from the advanced non-clear cell RCC (nccRCC) cohort of CheckMate 374. METHODS: Eligible patients received 0 to 3 prior systemic therapies. Patients received nivolumab 240 mg Q2W for ≤24 months or until confirmed progression or unacceptable toxicity. The primary endpoint was incidence of high-grade (grade 3-5) immune-mediated adverse events (IMAEs). Exploratory endpoints included objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: Forty-four patients had advanced nccRCC (papillary [n = 24], chromophobe [n = 7], unclassified [n = 8], other [n = 5]); 34.1% received ≥1 prior systemic regimen in the advanced/metastatic setting. With median follow-up of 11 (range, 0.4-27) months, no all-cause grade 3-5 IMAEs or treatment-related grade 5 adverse events were reported. ORR was 13.6% (95% confidence interval [CI], 5.2-27.4), with 1 complete response (chromophobe) and 5 partial responses (papillary [n = 2], chromophobe [n = 1], collecting duct [n = 1], and unclassified [n = 1] histology). Median PFS was 2.2 months (95% CI, 1.8-5.4). Median OS was 16.3 months (95% CI, 9.2-not estimable). CONCLUSIONS: Safety of flat-dose nivolumab 240 mg Q2W was consistent with previous results. Clinically meaningful efficacy was observed with responses in several histologies, supporting nivolumab as a treatment option for patients with advanced nccRCC, a patient population with high unmet need.

Safety and Efficacy of Nivolumab in Patients With Advanced Clear Cell Renal Cell Carcinoma: Results From the Phase IIIb/IV CheckMate 374 Study.

BACKGROUND: The open-label, phase IIIb/IV CheckMate 374 study (NCT02596035) was conducted to validate the safety and efficacy of flat-dose nivolumab monotherapy 240 mg every 2 weeks (Q2W) in previously treated advanced/metastatic renal cell carcinoma (RCC). Three cohorts included patients with predominantly clear cell histology, non-clear cell histologies, or brain metastases. We report safety and efficacy from the CheckMate 374 advanced clear cell RCC (ccRCC) cohort. PATIENTS AND METHODS: Eligible patients received prior treatment regimens (1-2 antiangiogenic; 0-3 systemic) with progression on/after last treatment and ≤ 6 months of enrollment. Patients received nivolumab 240 mg Q2W for ≤ 24 months or until confirmed progression/unacceptable toxicity. The primary endpoint was incidence of high-grade (grade 3-5) immune-mediated adverse events (IMAEs). Exploratory endpoints included objective response rate, progression-free survival, and overall survival. RESULTS: Ninety-seven patients had advanced predominantly ccRCC; 75.3% received only 1 prior systemic regimen in the advanced/metastatic setting. After a median follow-up of 17 months (range, 0.4-26.9 months), no grade 5 IMAEs occurred, and 9.3% of patients reported grade 3/4 IMAEs (hepatitis, 4.1%; diabetes mellitus, 2.1%; nephritis and renal dysfunction, 1.0%; rash, 1.0%; adrenal insufficiency, 1.0%). The objective response rate was 22.7% (95% confidence interval [CI], 14.8%-32.3%). Three patients had a complete response; 19 had partial responses. The median progression-free survival was 3.6 months (95% CI, 2.0-5.5 months). The median overall survival was 21.8 months (95% CI, 17.4 months to not estimable). CONCLUSIONS: This study validates the safety and efficacy of nivolumab 240 mg Q2W flat-dose monotherapy for previously treated advanced ccRCC and adds to previous safety and efficacy data using the 3 mg/kg Q2W dose.