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Abstract Aim In the registration trial, cabozantinib exposure ≥ 750 ng/mL correlated to improved tumor size reduction, response rate and progression free survival (PFS) in patients with metastatic renal cell cancer (mRCC). Because patients in routine care often differ from patients in clinical trials, we explored the cabozantinib exposure–response relationship in patients with mRCC treated in routine care. Methods Cabozantinib trough concentrations (Cmin) were collected and average exposure was calculated per individual. Exposure–response analyses were performed using the earlier identified target of Cmin > 750 ng/mL and median Cmin. In addition, the effect of dose reductions on response was explored. PFS was used as measure of response. Results In total, 59 patients were included:10% were classified as favourable, 61% as intermediate and 29% as poor IMDC risk group, respectively. Median number of prior treatment lines was 2 (0–5). Starting dose was 60 mg in 46%, 40 mg in 42% and 20 mg in 12% of patients. Dose reductions were needed in 58% of patients. Median Cmin was 572 ng/mL (IQR: 496–701). Only 17% of patients had an average Cmin ≥ 750 ng/mL. Median PFS was 52 weeks (95% CI: 40–64). No improved PFS was observed for patients with Cmin ≥ 750 ng/mL or ≥ 572 ng/ml. A longer PFS was observed for patients with a dose reduction vs. those without (65 vs. 31 weeks, p = .001). After incorporating known covariates (IMDC risk group and prior treatment lines (