November 01, 2016


 FDA seeks help limiting therapeutic durations

Posted Oct. 12, 2016

Federal drug authorities want help in defining therapeutic use durations for antimicrobials that are approved for use in livestock without defined limits.

The affected drugs are those administered in feed or water that are in the same antimicrobial classes as those used in human medicine. Food and Drug Administration officials are soliciting comments through Dec. 13 on how to define treatment duration limits, according to a Sept. 14 Federal Register notice.

“Establishing defined durations of use for currently approved therapeutics will support FDA’s efforts to foster stewardship of medically important antimicrobial drugs in food-producing animals and help preserve the effectiveness of these antimicrobials in animal and human medicine,” the notice states.

An April agency review found such antimicrobials are available for treatment of cattle, swine, chickens, turkeys, sheep, and bees.

“A key objective of FDA is to optimize the use of medically important antimicrobials by using a dosage strategy that maximizes drug effectiveness, minimizes target animal toxicity, and has an appropriately targeted duration of use to minimize the development of resistance to antimicrobial drugs of human medical importance,” the notice states.

Agency officials are seeking information on disease risks, treatment durations used in the absence of limits, evidence used in setting treatment durations, potential effects of defined durations, and currently available alternatives to antimicrobials.

More information is available at