Cabozantinib Demonstrates Real-World OS Benefit in Second-Line RCC

Janet Brown, MB BS, MSc, MD, FRCP

Cabozantinib (Cabometyx) as a second-line treatment showed improved overall survival (OS) outcomes compared with second-line axitinib (Inlyta) in patients with advanced renal cell carcinoma (RCC), according to a real-world analysis Public Health England’s Cancer Analysis System (CAS) that was presented at the 2021 ESMO Congress.¹

The study analyzed outcomes of adults who were diagnosed with stage III or IV RCC between January 1, 2011 and December 31, 2018, with follow-up lasting until January 31, 2020. A total of 440 patients received cabozantinib treatment, while 1045 received axitinib.

Median duration of treatment was longer for those who received cabozantinib (5.52 months; IQR, 2.73-11.74) than those on axitinib (4.60 months; IQR, 1.45-12.36).

Patients on cabozantinib – a TKI inhibitor – also had numerically longer median overall survival (OS) than patients given axitinib. In the unweighted analysis, median OS for cabozantinib was 11.41 months (IQR, 5.65-27.32) compared with 9.60 months (4.54-20.32). Similar results were found in the IPW analysis, with average OS lengths of 11.24 months (IQR, 5.65-27.98) and 10.39 months (IQR, 4.70-20.03) for the cabozantinib and axitinib arms, respectively.

“Both agents have been approved in the U.K. as second or later line treatment options for patients with advanced RCC – axitinib since 2012, and cabozantinib since 2016,” said study author Janet Brown, MB BS, MSc, MD, FRCP, Professor of Translational Medical Oncology at University of Sheffield, in her presentation of the data.

Notably, patients in the cabozantinib arm tended to have a more recent diagnosis, with 65% receiving a diagnosis between 2016 and 2018. Conversely, 80% of those on axitinib were diagnosed before 2016. In the United States, cabozantinib was approved by the FDA in December 2017 for first-line treatment, based on findings from the CABOSUN (NCT01835158) trial, which showed improved progression-free survival over sunitinib (Sutent), at 8.6 months and 5.3 months, respectively.

Characteristics between the cabozantinib and axitinib patient groups were otherwise balanced, with the average age being 62.5 years and 63.0 years, respectively. At diagnosis, 58.6% of patients in the cabozantinib cohort and 53.2% of those on the axitinib cohort had metastases, while 91.4% and 90.3%, respectively, had clear-cell histology. Regarding tumor size at diagnosis, 69.3% and 68.8% were 4.00 mm or smaller, in the cabozantinib and axitinib arms, respectively; 5.9% and 7.1% had tumors larger than 4.00 mm, and the remainder (24.8% and 24.1%) of patients had missing tumor sizes.

At diagnosis, 28.2% of patients given cabozantinib had an ECOG score of 0-1, compared with 20.4% of those on axitinib.

“Real-world evidence complements the results of randomized controlled trials,” Brown said. “This study demonstrates the potential for cabozantinib for conducting clinically relevant real-world research in England.”

Reference

1. Brown J, Harrow B, Marciniak A, McCarthy C, Cirneanu L, Protheroe A. Cabozantinib and axitinib after vascular endothelial growth factor therapy in patients with advanced renal cell carcinoma: a retrospective cohort study. Presented at: ESMO Congress 2021. September 16-21, 2021. Virtual. E-Poster 680P.