Impact of drug safety warnings and antimicrobial stewardship programme implementation on tigecycline prescribing: a prospective quasi-experimental interrupted time series analysis

Background Tigecycline is the first member of the glycylcyclines. Both the FDA (2010 and 2013) and the EMA (2011) issued safety warnings describing an increased mortality risk associated with tigecycline compared with other antibiotics treating severe infections. One of the best strategies to optimize antimicrobial therapies is through the establishment of antimicrobial stewardship programmes (ASPs) in hospitals. In June 2011, our ASP was implemented. Objectives To analyse trends in tigecycline prescription, after drug safety warning announcements by regulatory agencies and after an ASP implementation. Methods A 6 year prospective observational study of tigecycline use was performed, including all consecutive adult patients treated with at least one dose during the 6 years after approval of the drug for its use in the hospital. The primary outcome was tigecycline consumption assessed by DDD/100 bed-days. A segmented linear regression model for interrupted time series (ITS) was designed to detect any significant trend changes. Results A total of 524 patients were included. After the FDA warning alert, tigecycline consumption decreased by 35.9%. Moreover, following the ASP implementation, a dramatic reduction in tigecycline prescription by 67.3% was observed. Conclusions The role of the ASP was essential to establish adequate control of prescriptions, collaborating with the clinicians in a better adaptation of the tigecycline indication.