The randomised phase 2 CABOSUN trial comparing cabozantinib with sunitinib as initial therapy for advanced renal cell carcinoma (RCC) of intermediate or poor risk met the primary end-point of improving progression-free survival (PFS) as assessed by investigator. We report PFS by independent radiology review committee (IRC) assessment, ORR per IRC and updated overall survival (OS).
Previously untreated patients with advanced RCC of intermediate or poor risk by IMDC criteria were randomised 1:1 to cabozantinib 60 mg daily or sunitinib 50 mg daily (4 weeks on/2 weeks off). Stratification was by risk group and presence of bone metastases.
A total of 157 patients were randomised 1:1 to cabozantinib (n = 79) or sunitinib (n = 78). Median PFS per IRC was 8.6 months (95% confidence interval [CI] 6.8-14.0) versus 5.3 months (95% CI 3.0-8.2) for cabozantinib versus sunitinib (hazard ratio [HR] 0.48 [95% CI 0.31-0.74]; two-sided p = 0.0008), and ORR per IRC was 20% (95% CI 12.0-30.8) versus 9% (95% CI 3.7-17.6), respectively. Subgroup analyses of PFS by stratification factors and MET tumour expression were consistent with results for the overall population. With a median follow-up of 34.5 months, median OS was 26.6 months (95% CI 14.6-not estimable) with cabozantinib and 21.2 months (95% CI 16.3-27.4) with sunitinib (HR 0.80 [95% CI 0.53-1.21]. The incidence of grade 3 or 4 adverse events was 68% for cabozantinib and 65% for sunitinib.
In this phase 2 trial, cabozantinib treatment significantly prolonged PFS per IRC compared with sunitinib as initial systemic therapy for advanced RCC of poor or intermediate risk.
European journal of cancer (Oxford, England : 1990). 2018 Mar 15 [Epub ahead of print]
Toni K Choueiri, Colin Hessel, Susan Halabi, Ben Sanford, M Dror Michaelson, Olwen Hahn, Meghara Walsh, Thomas Olencki, Joel Picus, Eric J Small, Shaker Dakhil, Darren R Feldman, Milan Mangeshkar, Christian Scheffold, Daniel George, Michael J Morris
Dana-Farber/Partners CancerCare, Boston, MA, USA. Electronic address: ., Exelixis Inc., South San Francisco, CA, USA., Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA., Alliance Statistics and Data Center, Duke University, Durham, NC, USA., Massachusetts General Hospital Cancer Center, Boston, MA, USA., Alliance Protocol Operations Office, Chicago, IL, USA., Dana-Farber/Partners CancerCare, Boston, MA, USA., The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA., Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA., UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA., University of Kansas - Wichita, Wichita, KS, USA., Memorial Sloan Kettering Cancer Center, New York, NY, USA., Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA.