STERILITY TESTING ADVICE SHOULD BE DELETED FROM FDA's ASEPTIC PROCESSING

STERILITY TESTING ADVICE SHOULD BE DELETED FROM FDA's ASEPTIC PROCESSING draft guidelines, the Pharmaceutical Mfrs. Assn. (PMA) maintained in May 2 comments to the agency. In its discussion of sterility testing and the interpretation of retests, "the entire section on sterility testing," PMA said, "has introduced a number of new concepts. . .that are in conflict with the USP [U.S. Pharmacopeia], industry practice, and FDA regulations." The assn. recommended that the guidelines replace the sterility testing section with reference "to the interpretations made in USP XXI, general chapters 71 and 1211. Sterility testing "has been discussed in a number of forums, including public comment, by the USP Cmte. of Revision over the past five years, and the recommendations that now appear in USP XXI represent the consensus from that activity," PMA contended, noting that "FDA was a contributor and part of that consensus." The "guidance provided in these draft guidelines is in some respects contradictory to the USP and not representative of industry practice," the assn. asserted. FDA's draft guidelines on sterile drug products produced by aseptic processing were made public Feb. 1. The agency considers the subject important because it has perceived lack of uniformity in industry practices, unfamiliarity with FDA expectations, and frequent compliance problems. An example of discrepancy between the draft document and USP involves single positive findings of microbial growth. The draft states that it is "inappropriate to attribute an initial positive result to laboratory error merely because no growth is detected in repeated tests." PMA urged deletion of the sentence because "it contradicts the USP concept of second-stage testing." USP states: "If no microbial growth is found in the second stage and the documented review of appropriate records and the indicated product investigation does not support the possibility of intrinsic contamination, the lot may be considered to meet the requirements of a test for sterility." PMA also had several comments on the draft's advice concerning environmental quality, especially the particulate content of the air. For example, the document advised that the air in areas where unsterilized product, in-process materials, and containers or closures are prepared should have per-cubic-foot particle counts "of not more than 100,000 in a size range of 0.5 micron and larger. . .when measured in the area of the exposed articles during periods of activity." PMA urged that the standard be revised to indicate that such measurements be made "under static conditions." The assn. said that member firms "strongly object to the inclusion of this standard under the conditions specified. It would be extremely difficult, if not impossible, to maintain the specified particle counts during periods of activity if, for example, powders were being compounded."