Association of C-reactive protein with efficacy of avelumab plus axitinib in advanced renal cell carcinoma: long-term follow-up results from JAVELIN Renal 101

BACKGROUND: C-reactive protein (CRP) is an important prognostic and predictive factor in advanced renal cell carcinoma (aRCC). We report the association of CRP levels at baseline and early after treatment with efficacy of avelumab plus axitinib or sunitinib from the phase III JAVELIN Renal 101 trial. PATIENTS AND METHODS: Patients were categorized into normal (baseline CRP <10 mg/l), normalized (baseline CRP ≥10 mg/l and ≥1 CRP value decreased to <10 mg/l during 6-week treatment), and non-normalized (CRP ≥10 mg/l at baseline and during 6-week treatment) CRP groups. Progression-free survival and best overall response from the second interim analysis and overall survival (OS) from the third interim analysis were assessed. RESULTS: In the avelumab plus axitinib and sunitinib arms, respectively, 234, 51, and 108 patients and 232, 36, and 128 patients were categorized into normal, normalized, and non-normalized CRP groups. In respective CRP groups, objective response rates [95% confidence interval (CI)] were 56.0% (49.4% to 62.4%), 66.7% (52.1% to 79.2%), and 45.4% (35.8% to 55.2%) with avelumab plus axitinib and 30.6% (24.7% to 37.0%), 41.7% (25.5% to 59.2%), and 19.5% (13.1% to 27.5%) with sunitinib; complete response rates were 3.8%, 11.8%, and 0.9% and 3.0%, 0%, and 1.6%, respectively. Median progression-free survival (95% CI) was 15.2 months (12.5-21.0 months), not reached (NR) [11.1 months-not estimable (NE)], and 7.0 months (5.6-9.9 months) with avelumab plus axitinib and 11.2 months (8.4-13.9 months), 11.2 months (6.7-13.8 months), and 4.2 months (2.8-5.6 months) with sunitinib; median OS (95% CI) was NR (42.2 months-NE), NR (30.4 months-NE), and 23.0 months (18.4-33.1 months) and NR (39.0 months-NE), 39.8 months (21.7-NE), and 19.1 months (16.3-25.3 months), respectively. Multivariate analyses demonstrated that normalized or non-normalized CRP levels were independent factors for the prediction of objective response rate or OS, respectively, with avelumab plus axitinib. CONCLUSIONS: In patients with aRCC, CRP levels at baseline and early after treatment may predict efficacy with avelumab plus axitinib.