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.