LAUSR

Association Between Data Sources and US Food and Drug Administration Drug Safety Communications Drug safety communications (DSCs) are the primary tool for the US Food and Drug Administration (FDA) to communicate important new postmarketing safety information to patients and health care professionals.1 Drug safety communications are issued by the FDA for more than one-quarter of new drug and biologic approvals.2 There are known inconsistencies in issuing DSCs across national regulators.3 Less is known about the information source that typically serves as the basis of the initial safety signals that lead to DSCs, such as spontaneous reports aggregated through the FDA’s Adverse Event Reporting System (FAERS),4 results from randomized clinical trials (RCTs), or observational studies. Our objective was to describe the sources of the initial safety signals that lead to DSCs and examine their associations with drug characteristics and subsequent label changes.