The phase Ib JAVELIN Renal 100 study evaluates combination treatment comprising axitinib and avelumab in patients with advanced renal cell carcinoma. At the cut-off date in April 2017, 58% of a total of 55 patients had confirmed objective responses. Among all patients, 58% had grade ≥3 treatment-related adverse events. Five patients died owing to disease progression and one patient died of treatment-related autoimmune myocarditis. The maximum tolerated combination dose was 5 mg twice daily for axitinib and 10 mg/kg every 2 weeks for avelumab.