Table 3.

Common concerns, with applicable resources and references, raised by the US Food and Drug Administration (FDA) during review of premarket submissions for catheters with additives, coatings, impregnations, or bondings

Category	Main Issues of FDA Concern Missing or Insufficient in Submissions
Performance testing considerations	In vitro test methods to assess pathogen killing: quantitative time-kill assays (i.e., log reduction of the challenge organism) measure the amount of organism killed. Consideration should be given to calculation of the log reduction of any additive or coating relative to the uncoated control. For the uncoated control method, the following could be considered:
	Assay conditions that simulate, as closely as possible, actual use
	Clinically relevant pathogens
	Results on the fully finished catheter