Effect of European Medicines Agency's regulatory measures on nimesulide utilization in Portugal

Purpose: Severe hepatic adverse events led the European Medicines Agency to recommend restrictions on nimesulide use. Our aim was to determine their effect on nimesulide dispensing in Portugal. Methods: Interrupted time-series using pharmacy billing records of the Portuguese National Health Service. Regulatory actions, concurrent events, and nimesulide dispensing were recorded from 2006 to 2015. The primary outcome was the number defined daily doses (DDD) of nimesulide dispensed per month. Secondary outcomes were the number of adverse reactions to nimesulide and the variation of nimesulide prescriptions by prescribing site category. Results: We defined 3 possible interruption periods: (1) May 2007 to March 2008: nimesulide was withdrawn from Ireland, the European Medicines Agency initiated a safety review, and this was reported by Portuguese media; (2) October 2009 to April 2010: the European Commission reached a decision and mandated a broader safety review; and (3) December 2010 to April 2012: the Commission's decision was implemented in Portugal, the broader safety review was concluded and implemented. Nimesulide use showed a declining trend at the start of the series (-12.2 thousand DDD/month). Interruptions 1 and 3 were associated with decreases in level (-824.7 thousand and -449.0 thousand DDD, respectively). Interruption 3 was associated with a greater decrease in primary care than in other sites. The number of reported adverse events did not decrease. Conclusions: Nimesulide use decreased significantly following 2 complex interventions including regulatory measures, media reports, and other concurrent factors. However, this was not associated with a decrease in reported adverse drug reactions.