OBJECTIVE: Clinical trials have demonstrated the efficacy and safety of avelumab + axitinib in patients with advanced clear cell renal cell carcinoma (ccRCC). However, information is limited regarding the activity of avelumab + axitinib in patients with non-clear cell RCC (nccRCC). In Japan, post-marketing surveillance (PMS) of patients with RCC receiving avelumab + axitinib treatment in general clinical practice was undertaken. We report ad hoc analyses of PMS data according to RCC pathological classification. METHODS: Of 328 patients with RCC who received ≥1 dose of avelumab and were enrolled between December 2019 and May 2021, 271 (82.6%) had ccRCC, 22 (6.7%) had nccRCC, and 35 (10.7%) had missing or unknown RCC pathology. Among patients with nccRCC, pathological subtypes were papillary in 12 (3.7%), translocation in 3 (0.9%), acquired cystic disease associated in 3 (0.9%), chromophobe in 2 (0.6%), mucinous tubular and spindle cell in 1 (0.3%), and Bellini duct in 1 (0.3%). RESULTS: Among patients with ccRCC or nccRCC, any-grade adverse drug reactions of safety specifications occurred in 140 (51.7%) and 15 (68.2%), and of grade ≥3 in 48 (17.7%) and 6 (27.3%), respectively. The objective response rate in patients with ccRCC or nccRCC was 36.9% and 22.7%, respectively
in patients with papillary tumors, it was 33.3%. Median overall survival was not reached in patients with ccRCC or nccRCC, and 12-month overall survival rates were 86.8% and 76.7%, respectively. CONCLUSIONS: Overall, subgroup analyses of PMS data suggest that avelumab + axitinib improved clinical outcomes in nccRCC in addition to ccRCC.