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In its Measure 17 (Theme 2), the EcoAntibio 2017 Plan provides for maintaining the MAs of older antibiotics regarded as non-critical for human medicine, and in particular focusing on revalidation of the therapeutic regimens. Feedback from use in the field indicates dosages that are ill suited to certain bacterial populations encountered in the targeted diseases. In addition, the development of knowledge of pharmacokinetics (PK) and pharmacodynamics (PD), and of the PK/PD relationships of antibiotics, has made it possible in some cases to assess the relevance of the dosages, while taking into account the risk of selection of antibiotic resistance in the targeted bacteria. In the framework of this internal request, a Working Group (WG) was set up to define a methodology for revising the dosages of older antibiotics, encompassing both animal and public health objectives. The actual revision of the dosages of older antibiotics will need to be conducted at the European level, where this methodology will be proposed. The conclusions of the work following this internal request are therefore not designed to recommend doses for older antibiotics, but rather to define a scientifically robust methodology for their revision.
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