TSEAC

July 17 & 18, 2003

 

TOPIC #3

CDRH Charge for the Panel:

 

 

 

         To learn what published data can be used to establish methods for decontaminating medical devices after potential TSE-exposure

 

         To learn what limitations exist in applying these data to procedures that decontaminate medical devices

 

         To discuss methods for validating the sterility of medical devices regarding bacteria and viruses

 

         To learn how these approaches (or others) can be employed in designing and interpreting TSE inactivation studies.

Questions for the TSEAC Panel:

 

 

What information in the published literature should be viewed as supportive data to validate the methods and procedures for reprocessing medical devices potentially contaminated with TSE?

 

What elements (e.g. the material used for device fabrication, device design, method for cleaning, intended use) should be considered in designing a validation study to demonstrate that a reprocessed medical device contaminated or potentially contaminated with a TSE agent is safe for reuse?

 

Medical devices potentially exposed to TSE can include surgical instruments such as scalpels, neuro burrs, neuro drill bits, neural electrodes, endoscopic devices, sterilizers and accessories such as sterilization trays. These medical devices are available in several different sizes, design configurations, and materials.

 

Please discuss the factors to consider when determining whether a validated reprocessing method can be applied to any given device. When will additional validation studies be needed for a specific device design?

 

4. What criteria should be considered when analyzing the results of such studies? For example is log reduction of the TSE infectivity, expressed as LD50, an appropriate endpoint for such methods? If so, what magnitude of log reduction would be considered safe? Are there other endpoints, such as the presence of PrPres that would be acceptable surrogate markers for infectivity?

5. The extent of TSE inactivation required for any reprocessing procedure depends on the amount of infectious agent present in the device.

Please discuss the current scientific information which describes the level of infectious material found in different human tissues and possibly the contaminated medical devices.

Please discuss how this information should be considered in designing the validation studies.