Safety of pazopanib and sunitinib in treatment-naive patients with metastatic renal cell carcinoma: Asian versus non-Asian subgroup analysis of the COMPARZ trial

Background: The international, phase 3 COMPARZ study demonstrated that pazopanib and sunitinib have comparable efficacy as first-line therapy in patients with advanced renal cell carcinoma, but that safety and quality-of-life profiles favor pazopanib. Our report analyzed pazopanib and sunitinib safety in Asian and non-Asian subpopulations. Methods: Patients were randomized 1:1 to receive pazopanib 800 mg once daily (continuous dosing) or sunitinib 50 mg once daily in 6-week cycles (4 weeks on, 2 weeks off). Results: Safety population was composed of 363 Asian patients and 703 non-Asian patients. Asian patients had similar duration of exposure to either drug compared with non-Asian patients, although Asian patients had a higher frequency of dose modifications. Overall, hematologic toxicities, cytopenias, increased AST/ALT, and palmar-plantar erythrodysesthesia (PPE) were more prevalent in Asian patients, whereas gastrointestinal toxicities were more prevalent in non-Asian patients. Among Asian patients, hematologic adverse events and most non-hematologic AEs were more common in sunitinib-treated versus pazopanib-treated patients. Among Asian patients, the most common grade 3/4 AEs with pazopanib were hypertension (grade 3, 22%) and alanine aminotransferase increased (grade 3, 12%; grade 4, 1%); the most common grade 3/4 AEs with sunitinib were thrombocytopenia/platelet count decreased (grade 3, 36%; grade 4, 10%), neutropenia/neutrophil count decreased (grade 3, 24%; grade 4, 3%) hypertension (grade 3, 20%), and PPE (grade 3, 15%). Conclusions: A distinct pattern and severity of adverse events was observed in Asians when compared with non-Asians with both pazopanib and sunitinib. However, the two drugs were well tolerated in both subpopulations. Trial registration: ClinicalTrials.gov, NCT00720941, Registered July 22, 2008 ClinicalTrials.gov,