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  5. Clarithromycin (marketed as Biaxin) Information
  1. Postmarket Drug Safety Information for Patients and Providers

Clarithromycin (marketed as Biaxin) Information

FDA ALERT [12/2005]: 

FDA has learned of a placebo controlled study of patients in Denmark with heart disease (the CLARICOR Study), reporting increased mortality in patients treated with clarithromycin (14 days) compared with patients who received a placebo (http://bmj.bmjjournals.com/cgi/rapidpdf/bmj.38666.653600.55v1). The observed difference in mortality became apparent after patients had been followed for one year or longer after the study drug was given.  A mechanism by which two-weeks of clarithromycin could cause increased mortality measured after one year or longer is not clear.  Previous trials of antibacterial drugs to prevent heart disease and other trials of clarithromycin have not shown a statistically significant effect on mortality.  Considering the results from the CLARICOR study and the results from previous studies of antibacterial drugs to prevent heart disease, the FDA is not recommending any specific changes to the use of clarithromycin at this time.   FDA has discussed these findings with the Danish Medicines Agency (DMA) and the FDA recommendation is consistent with that of the DMA.   The FDA is providing the summary below to physicians and patients so that they can be aware of the information currently available.  The FDA is attempting to get more information regarding the CLARICOR study and its findings. 

This information reflects FDA’s preliminary analysis of data concerning this drug.  FDA is considering, but has not reached a final conclusion about this information.  FDA intends to update this page when additional information or analyses become available.

Related Information

Labeling and Regulatory History from Drugs@FDA

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