Use of a Healthcare Claims Database for Post-Marketing Safety Assessments of Eribulin in Japan: A Comparative Assessment with a Prospective Post-Marketing Surveillance Study

The study analyzed data from 551 patients in a healthcare claims database (DB) and 951 patients in a prospective post-marketing surveillance (PMS) to compare the safety profiles of eribulin mesylate, a breast cancer treatment, in Japan. While patient characteristics and drug use were generally similar between the two groups, there were significant differences in the reported incidence of adverse events (AEs), such as nausea, neutropenia, stomatitis, and alopecia. The study also noted a trend of increasing eribulin administrations and decreasing concomitant hormone therapy use over time, as well as a significant decrease in the incidence of anemia and pyrexia from 2011 to 2016. The findings suggest that healthcare claims databases can complement PMS in pharmacovigilance, despite potential under- or over-reporting of some AEs in the DB. The study was funded by Eisai Co. Ltd., with authors affiliated with the company and Clinical Study Support, Inc.