European Pharmacopoeia sterility testing

Recognizing these problems, UK food regulatory authorities have generally abandoned the use of quantitative microbial counts as enforceable standards of food quality. Despite this, the European Pharmacopoeia has introduced both quantitative and qualitative mierobial standards for non-sterile medicines, which might become enforceable in some member states. It prescribes varying maximum total microbial levels and exclusions of particular species according the routes of administration. The British Pharmacopoeia has now ineluded these tests, but suggest they should be used... 

Both the British and European pharmacopoeias indicate that it is necessaiy to conduct control tests which confirm the adequacy of the facilities by sampling of air and surfaces and carrying out control tests using samples known to be sterile. In reahty, this means... 

Specific details of the sterility testing of parenteral products, ophthalmic and other non-injectable preparations, catgut, surgical dressings and dusting powders will be found in the British and European pharmacopoeias. 

The pharmacopeial standard applying to sterile products is that they must be capable of passing a Test for Sterility. A Test for Sterility is described in U.S. Pharmacopeia (USP) under Section 71 and in the European Pharmacopoeia (PhEur) under Section 2.6.1. These were harmonized along with the Japanese Pharmacopoeia and the requirements of the Australian Therapeutic Goods Administration in 1999, but they still have some minor differences in detail. 

The inadequacies of the Test for Sterility are acknowledged in the pharmacopoeias themselves. The European Pharmacopoeia does not have a long his-tory of publication three of its four fascicules cany a disclaimer to the Test for Sterility. Only in 1971 did the EP publish an imembellished method description and sampling plan. Each of its next revisions, EP 1978, EP 1980. and EP 1986 start their sections headed Test for Sterility with an italicized paragraph stating the following ... 

STERILITY Sterility is the absence of living organisms. The conditions of the sterility test are given in the European or other relevant Pharmacopoeia ... 

After several years of negotiation the sterility tests of the European Pharmacopoeia, The United States Pharmacopeia and the Japanese Pharmacopoeia are harmonised [59]. In the next sections the five steps of this harmonised test, as described in Ph. Eur. 2.6.1 will be discussed sampling, sample preparation, inoculation, incubation, and interpretation. Prior to the routine application of the test, a suitability test with a range of specified test organisms shall demonstrate that growth of these organisms is not inhibited due to residual antimicrobial activity of the product. 

S. Tellez, R. Casimiro, A. I. Vela, J. F. Fernandez-Garayzabal, R. Ezquerra, M. V. Latre, V. Briones, J. Goyache, R. Bullido, M. Arboix and L. Dominguez, Unexpected inefficiency of the European pharmacopoeia sterility test for detecting contamination in clostridial vaccines. Vaccine, 2006, 24, 1710-1715. 

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