EMA (European Medicines Agency) answers at random intervals questions arising from the EC GMP Guideline and its Annexes. Actually, two questions on the topic bioburden from Annex 1 "Manufacture of Sterile Medicinal Products" are answered:
Where should bioburden monitoring take place for an aseptically produced product?
Annex 1 describes that the bioburden should be monitored before each sterilisation and testing should be performed on each batch. For routine commercial manufacturing, bioburden testing should be performed on the bulk solution, immediately before its sterile filtration. If a prefilter is additionally installed, then sampling for bioburden testing should be performed prior to the prefiltration, provided that the actual filtration is carried out immediately afterwards!
What is the maximum accepted bioburden level?
With reference to the EMA Human and Veterinary Notes for Guidance on Manufacture of the Finished Dosage Form (CPMP/QWP/486/95 and EMEA/CVMP/126/95) a bioburden limit of no more than 10 CFU/100 ml is specified. When a prefilter is installed, this value should also be achieved prior to the prefilter. Higher bioburden limits should not be justified by the higher capacity of two consecutive bacteria retaining filters.
Exceptions can be made in the areas of fermentation or biological or herbal components, or if purified water is used for ophthalmic preparations. But, in such cases, it should be demonstrated that the prefilter has the capability to achieve a bioburden prior to the last filtration of no more than 10 CFUs/100 ml.
Sources:
CPMP/QWP/486/95 - Committee for proprietary medicinal products -
Note for Guidance on Manufacture of the Finished Dosage Form
EMEA/CVMP/126/95: Committee for veterinary medicinal products -
Note for Guidance: Manufacture of the Finished Dosage Form
5. For an aseptically produced product, where should bioburden monitoring take place? H+V May 2013According to the EU
GMP guideline
(annex 1), the bioburden should be monitored before sterilisation and testing should be performed on each batch.
For routine commercial manufacturing, bioburden testing should be performed on the bulk solution, immediately before its sterile filtration. If a presterilising filter is additionally installed, then sampling for bioburden testing may be performed prior to the prefiltration, provided that no holding time is scheduled for the solution between the two filtration steps.
Section 80:
New text:Thebioburdenshouldbemonitoredbeforesterilisation.Thereshouldbe
workinglimitsoncontaminationimmediatelybeforesterilisation,whicharerelatedto
theefficiencyof themethod tobeused.Bioburdenassay shouldbeperformedon
PI0322 8of11 8January2010
each batch for both aseptically filled product and terminally sterilised products.
Where overkill sterilisation parameters are set for terminally sterilised products,
bioburdenmight bemonitored only at suitable scheduled intervals. For parametric
release systems, bioburden assays should be performed on each batch and
consideredasan inprocess test.Whereappropriate the levelofEndotoxinsshould
be monitored. All solutions, in particular large volume infusion fluids, should be
passedthroughamicroorganismretainingfilter,ifpossiblesitedimmediatelybefore
filling.
Interpretation:
General:Thecontribution tobioburdenof thevarious rawmaterialsandpackaging
materials together with themanufacturing processes prior to the sterilisation step
should be understood and controlled. Amonitoring and control strategy including
periodicmonitoringand trendingofbioburdenprior toanybioburden reductionstep
shouldbeestablishedand justifiedon thebasisofprocess risks.Volumessampled
shouldbejustifiedandtakeaccountoftheexpectedlevelofcontamination
The bioburden should at least be determined for the product prior to the final
sterilizationstep.Acceptancecriteria forbioburdenmustbebasedon thesterilising
step, a sterility assurance level of 106
must bemet.The results of the bioburden
assaysmustbepresentbeforerelease(unlessanoverkillcycle isused for terminal
sterilisation).Thisfavourstheuseofrapidmicromethods.
Ariskassessmentshouldbeperformedinordertodeterminetheneedforendotoxin
studies.Whenneeded,endotoxinsshouldbedeterminedalsofortheunitsofproduct
thatwerefilledthelast.
Terminal sterilisation: For terminal sterilisation the F0 value has to be taken into
account.Thesamplingshouldbeperformedonfilledcontainerspriortosterilisation.
For overkill sterilisation processes for terminally sterilized products, the company
mustjustifytheintervalschosenforbioburdentesting.
Aseptic operations: For sterile filtration, filter efficacy studiesmust be taken into
accountwhendeterminingtheacceptancecriteriaforthebioburdenpriortofiltration.
This means that if two subsequent filtration steps are used, product has to be
sampledprior to the last filtrationstep, if technicallypossible,e.g. first filtration into
bulk tank, second filtration immediately prior to filling.However, if a system of two
filterswith redundancy isused (thesecond filter isused forsecurity, ifone fails the
required SAL is still achieved), sampling should be performed upstream of these
filters inordernot to compromise the filtrationstep.The companyhas to justify its
approachifsamplingisdonebeforethefirstfiltrationstep.