Postmarketing observational study of pazopanib in patients with metastatic soft tissue sarcoma in Japan.

BACKGROUND: This study evaluated the safety and efficacy of pazopanib in patients with metastatic soft tissue sarcoma in routine clinical use in Japan. METHODS: It was a multicentre, centrally registered and uncontrolled observational study in patients who received pazopanib for metastatic soft tissue sarcoma, with an observation period of 1 year after the start of drug administration. The study was conducted at 378 investigational sites in Japan from September 2012 to September 2019. Progression-free survival (PFS) and overall survival (OS) were the efficacy endpoints of the study. RESULTS: A total of 1970 patients were enrolled. Of these, 680 with finalized study forms were included in the analysis. Overall, 649 patients were included in the safety analysis set, and 569 were included in the efficacy analysis set. Most of the patients (81.97%) experienced at least one adverse drug reaction (ADR); 22.34% of patients reported serious ADRs and 34.98% of patients experienced grade ≥ 3 ADRs in the safety set. Hypertension (40.37%) and hepatic dysfunction (26.50%) were the two most common ADRs. A total of 262 deaths were reported, of which 12 were due to ADRs. The median PFS was 3.09 months, whereas the median OS was not reached at the end of the 1-year observation period. CONCLUSIONS: The safety and efficacy profiles in this postmarketing observational study were consistent with prior data and registration clinical trials. No new safety signals were observed while treating patients with metastatic soft tissue sarcoma with pazopanib.

A randomized, double-blind, placebo-controlled, Phase III study of pazopanib in patients with soft tissue sarcoma: results from the Japanese subgroup.

OBJECTIVE: This analysis of the Japanese subpopulation of the PALETTE Phase III, randomized, placebo-controlled study investigated efficacy and safety of pazopanib in patients with metastatic soft tissue sarcoma after failure of standard chemotherapy. METHODS: Patients were randomly assigned in a 2:1 ratio to receive either pazopanib 800 mg once daily or placebo, with no subsequent cross-over. Primary endpoint was progression-free survival. Secondary endpoints included overall survival and overall response rate. Efficacy analysis was by intent-to-treat. Safety was also investigated. RESULTS: Forty-seven patients received either pazopanib (n = 31) or placebo (n = 16). Median progression-free survival was 7.0 weeks (95% confidence interval: 4.0-11.7) for placebo and 24.7 weeks (95% confidence interval: 8.6-28.1) for pazopanib (hazard ratio = 0.41 [95% confidence interval: 0.19-0.90]; P = 0.002). Median overall survival was 14.9 months (95% confidence interval: 6.8-not calculable) for placebo and 15.4 months (95% confidence interval: 7.9-28.8) for pazopanib (hazard ratio = 0.87 [95% confidence interval: 0.41-1.83]; P = 0.687). More patients receiving pazopanib experienced best response of stable disease versus placebo. Adverse events were similar to the global population; those leading to dose reduction were more common and mean daily dose was lower in the Japanese population versus the global population (45 vs. 32% and 624.4 vs. 700.4 mg, respectively). CONCLUSIONS: The efficacy and safety of pazopanib observed in the Japanese subpopulation of PALETTE were similar to those in the global population. Pazopanib is a new treatment option for Japanese patients with metastatic non-adipocytic soft tissue sarcoma after chemotherapy. CLINICAL TRIAL REGISTRATION NUMBER: NCT00753688; GSK study ID: VEG110727; http://www.gsk-clinicalstudyregister.com/study/VEG110727#ps.