RESUMO
PURPOSE: This study characterizes drug safety-related label changes by evidence source contribution, time from drug approval to label change, initiator (FDA or sponsor), and drug class. METHODS: A retrospective review of the FDA's internal files was used to obtain regulatory documentation on drugs undergoing a 2010 label change. Contribution of evidence sources were identified and label change initiator and drug class were determined for each drug. RESULTS: A total of 371 drugs were analyzed. Spontaneous reports contributed to 52% and 55% of label changes when analyzed by unique safety issue and drug, respectively. The median time from approval to 2010 safety-related label change was 11 years. The sponsor was more likely than the FDA to initiate a label change (58% and 42%). Label changes were most common among nervous system drugs (23%), antiinfectives for systemic use (17%), and cardiovascular system drugs (14%). CONCLUSIONS: Drug label changes involve contributions from multiple evidence sources. The findings from this comprehensive review are consistent with previous findings and demonstrate (i) the continued importance of the spontaneous reporting system and complementary evidence sources and (ii) safety-related label changes take place years after postmarket approval, emphasizing the importance of continued drug safety surveillance throughout a product's lifecycle.