Reactions 1388 - 11 Feb 2012

US FDA 2009 drug safety warningsanalysed

"Improving postmarket drug safety requires timelierascertainment of drug risks together with higher qualityand better documented scientific evidence" conclude DrThomas Moore and colleagues from the US after theyanalysed US FDA drug safety warnings in 2009.

There were 181 FDA approved major safetyregulatory actions in 2009, including the withdrawal ofefalizumab [Raptiva], 25 new boxed warnings, 19 newcontraindications, 90 new warnings and 46 revisions ofprevious actions. Some of the most extensive changesinvolved class warnings. Based on findings of a largeFDA meta-analysis, 19 antiepilepsy drugs received thesame suicidal behaviour warning, even drugs notincluded in the meta-analysis and drugs with differingmechanisms of action. The FDA also added similarsuicidal behaviour and violence warnings to thesmoking cessation therapies varenicline [Chantix] andbupropion [Zyban], despite an FDA study showinghigher risks and 10 times as many reports withvarenicline.

The regulatory actions occurred a median of 11 yearsafter drug approval (≥ 15 years for 61 of the drugs); only36 of the actions involved drugs approved within thepast 5 years. ADR reports from drug manufacturers orthrough MedWatch formed the basis of 57% of newregulatory actions and 76% of new boxed warnings,often with little or no details provided.

Clinical studies were cited as the evidence for 19% ofnew regulatory actions, but only two actions werederived from statistically significant differences and onewas based on a single study case.Moore TJ, et al. The FDA and new safety warnings. Archives of Internal Medicine172: 78-80, No. 1, 9 Jan 2012. Available from: URL: http://dx.doi.org/10.1001/archinternmed.2011.618 803066736

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Reactions 11 Feb 2012 No. 13880114-9954/10/1388-0001/$14.95 © 2010 Adis Data Information BV. All rights reserved