PDA Letter Article

Sterilizing Grade Filters and PUPSIT

by A Statement From Four Filter Manufacturers

Filter Photo

Recent statements made by European regulators to justify the pre-use/post-sterilization integrity test (PUPSIT) require clarification.

The statements indicated that filter manufacturers have weaknesses within their quality control functions that may create risks, thereby, requiring a pre-use, post-sterilization integrity test (PUPSIT). The statements included:

  • Filter manufacturers have no transport qualification and lack control over the transport of the filter elements shipped
  • Filter manufacturers do not control the outsourced gamma sterilization of their filter units, and, therefore, do not detect weaknesses
  • The quality control of the filter manufacturing processes and the release criteria are insufficient and weak
  • An anecdotal conversation alluded to an experience of a filter flaw that was masked by blockage of the filter

We believe these statements require substantial clarification.