Safety information in drug labeling: a comparison of the USA, the UK, and Japan

Abstract

Despite globalization of drug approvals, there is a disparity in drug safety regulations among the USA, Europe, and Japan. We sought to determine differences in safety information on drug labels among the three regions. This was a cross-sectional study with quantitative survey of safety information on labels of 189 new molecular entities approved in the USA, the UK, and Japan. Outcome measures were the proportions of total safety information (PSI), of contraindications (PCI), and of boxed warnings (PBW) to all information on the label. We identified a boxed warning (BW) on US and Japanese labels through a manual search. These measures were analyzed according to therapeutic indications. On the Japanese labels, PSI was smaller than that on the US and UK labels for cardiovascular diseases. For neoplastic and immunologic diseases, PSI on the Japanese labels was larger than that on the UK labels. For nervous system diseases, PSI on the US labels was larger than that on the UK and the Japanese labels. PCI showed contrasting results with PSI except for neoplastic and immunologic diseases. BWs showed a poorer concordance between the USA and Japan in hematologic and genitourinary diseases than in other therapeutic areas. Substantial differences in safety information exist depending upon outcome measures and therapeutic areas among the US, the UK, and the Japanese labels. This underscores the need for further analyses to determine causes of these differences to optimize drug safety regulations.