Results from a phase Ib/II study published in Journal of Clinical Oncology last month show encouraging activity of a novel immunotherapy and VEGF inhibitor combination in metastatic renal cell carcinoma (mRCC).
In the phase Ib part of the study, which was used to find the safest and most tolerated dose of the combination, there were no dose-limiting toxicities. The highest tested dose level of pembrolizumab and bevacizumab (200 mg pembrolizumab and bevacizumab 15 mg/kg every 3 weeks) was used as the dose in the phase II part of the study. Forty-eight untreated patients with metastatic RCC were enrolled in the phase II part of the study. The objective response rate was 60.9% and progression-free survival was 20.7 months. Severe or life-threatening adverse events occurred in 45% of the patients, and 33% of patients stopped treatment because of adverse events.
In conclusion, this study highlights acceptable tolerability for the combination of pembrolizumab and bevacizumab for untreated metastatic RCC patients. The combination also showed promising activity for the first-line treatment of metastatic RCC. Larger, prospective clinical trials with this first-line combination of pembrolizumab plus bevacizumab are needed to confirm efficacy and positioning in the patient pathway for metastatic RCC.