Real-world Practice Patterns and Safety of Concurrent Radiotherapy and Cabozantinib in Metastatic Renal Cell Carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium

Cabozantinib in the Routine Management of Renal Cell Carcinoma: A Systematic Literature Review of Real-World Evidence

Real-world cabozantinib use has increased since its approval to treat patients with advanced renal cell carcinoma (RCC) in 2016. We reviewed cabozantinib use in real-world clinical practice and compared outcomes with pivotal cabozantinib randomized control trials (RCTs). This PRISMA-standard systematic literature review evaluated real-world effectiveness and tolerability of cabozantinib in patients with RCC (PROSPERO registration: CRD42021245854). Systematic MEDLINE, Embase, and Cochrane database searches were conducted on November 2, 2022. Eligible publications included ≥ 20 patients with RCC receiving cabozantinib. After double-screening for eligibility, standardized data were abstracted, qualitatively summarized, and assessed for risk of bias using the Newcastle-Ottawa Scale. Of 353 screened publications, 41 were included, representing approximately 11,000 real-world patients. Most publications reported cabozantinib monotherapy cohort studies (40/41) of retrospective (39/41) and multicenter (32/41) design; most included patients from North America and/or Europe (30/41). Baseline characteristics were demographically similar between real-world and pivotal RCT populations, but real-world populations showed greater variation in prevalence of prior nephrectomy, multiple-site/brain metastasis, and nonclear-cell RCC histology. Cabozantinib activity was reported across real-world treatment lines and tumor types. Overall survival, progression-free survival, and objective response rate values from pivotal RCTs were within the ranges reported for equivalent outcomes across real-world studies. Common real-world grade ≥ 3 adverse events were consistent with those in pivotal RCTs (fatigue, palmar-plantar erythrodysesthesia syndrome, diarrhea, hypertension), but less frequent. No new tolerability concerns were identified. Real-world RCC survival outcomes for cabozantinib monotherapy were broadly consistent with pivotal RCTs, despite greater heterogeneity in real-world populations.

Cabozantinib and Axitinib After Vascular Endothelial Growth Factor Therapy in Patients with Advanced Renal Cell Carcinoma: A Retrospective Cohort Study from England

BACKGROUND AND OBJECTIVE

The tyrosine kinase inhibitors cabozantinib and axitinib have been widely used in England to treat advanced renal cell carcinoma following prior vascular endothelial growth factor-targeted therapy, but data on real-world usage remain limited. Our objective was to describe the real-world treatment patterns and outcomes of patients with advanced renal cell carcinoma who received second-line or later-line (≥ 2L) cabozantinib or axitinib after vascular endothelial growth factor-targeted therapy in clinical practice in England.

METHODS

This retrospective cohort study used clinical practice data (collected 2011-20) from the English Cancer Analysis System database. Patient characteristics, treatment sequence and duration, and overall survival (time from initiation of cabozantinib/axitinib treatment to death) were evaluated.

RESULTS

Data from 1485 eligible adults with advanced renal cell carcinoma were analyzed: 440 received ≥  2L cabozantinib (2L for 88.6% of them); 1045 received ≥  2L axitinib (2L for 89.5%). The most common first-line treatments were sunitinib (2L cabozantinib subcohort, 48%; 2L axitinib subcohort, 46%) and pazopanib (46% and 54%, respectively); nivolumab was the most common third-line treatment (18% and 19%, respectively). Median (interquartile range) 2L therapy duration was 5.52 (2.73-11.74) months for cabozantinib and 4.60 (1.45-12.36) months for axitinib. Following adjustment for potential confounders using inverse probability weighting, overall survival (median [interquartile range]) was longer for ≥ 2L cabozantinib (11.2 [5.7-28.0] months) than for ≥  2L axitinib (10.4 [4.7-22.0] months; log-rank p = 0.0034).

CONCLUSIONS

The Cancer Analysis System database is a valuable research resource providing extensive real-world clinical data. Real-world overall survival was longer with ≥  2L cabozantinib than with axitinib.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT04637204; registered November 2020.

Local Liver Irradiation Concurrently Versus Sequentially with Cabozantinib on the Pharmacokinetics and Biodistribution in Rats

The aim of this study was to evaluate the radiotherapy (RT)-pharmacokinetics (PK) effect of cabozantinib in concurrent or sequential regimens with external beam radiotherapy (EBRT) or stereotactic body radiation therapy (SBRT). Concurrent and sequential regimens involving RT and cabozantinib were designed. The RT–drug interactions of cabozantinib under RT were confirmed in a free-moving rat model. The drugs were separated on an Agilent ZORBAX SB-phenyl column with a mobile phase consisting of 10 mM potassium dihydrogen phosphate (KH2PO4)–methanol solution (27:73, v/v) for cabozantinib. There were no statistically significant differences in the concentration versus time curve of cabozantinib (AUCcabozantinib) between the control group and the RT2Gy×3 f’x and RT9Gy×3 f’x groups in the concurrent and the sequential regimens. However, compared to those in the control group, the Tmax, T1/2 and MRT decreased by 72.8% (p = 0.04), 49.0% (p = 0.04) and 48.5% (p = 0.04) with RT2Gy×3 f’x in the concurrent regimen, respectively. Additionally, the T1/2 and MRT decreased by 58.8% (p = 0.01) and 57.8% (p = 0.01) in the concurrent RT9Gy×3 f’x group when compared with the control group, respectively. The biodistribution of cabozantinib in the heart increased by 271.4% (p = 0.04) and 120.0% (p = 0.04) with RT2Gy×3 f’x in the concurrent and sequential regimens compared to the concurrent regimen, respectively. Additionally, the biodistribution of cabozantinib in the heart increased by 107.1% (p = 0.01) with the RT9Gy×3 f’x sequential regimen. Compared to the RT9Gy×3 f’x concurrent regimen, the RT9Gy×3 f’x sequential regimen increased the biodistribution of cabozantinib in the heart (81.3%, p = 0.02), liver (110.5%, p = 0.02), lung (125%, p = 0.004) and kidneys (87.5%, p = 0.048). No cabozantinib was detected in the brain in any of the groups. The AUC of cabozantinib is not modulated by irradiation and is not affected by treatment strategies. However, the biodistribution of cabozantinib in the heart is modulated by off-target irradiation and SBRT doses simultaneously. The impact of the biodistribution of cabozantinib with RT9Gy×3 f’x is more significant with the sequential regimen than with the concurrent regimen.