Microbiological Validation

Mark OldcorneWrexham Maelor Hospital

What is Validation?

The QA of any preparation activity is reliant on the satisfactory validation of the procedures

Validation should demonstrate that the overall process will reproducibly provide a product that complies with its specification

What is validation? Action of proving, in accordance

with the principles of GMP, that any procedure, process, equipment, material, activity or system leads to the expected results

Action of proving (and documenting) that something ‘works’

5 Pillars of GMP Premises People Processes Products Procedures

Profit!!!

Overview

Microbiological validation of Premises

environmental monitoring cleaning and disinfection

People operator broth transfer tests hand cleaning and disinfection

Overview Processes

process broth tests transfer spraying validation gassing processes

Products sterility tests

Underpinned by Procedures(parametric release!)

Validation Master Plan Part of

QA programme Site Master File

Schedules Methods Responsibilities

MicrobiologicalValidation Methods

Physical - AHU\filtrationPhysical - AHU\filtration

Microbiological - Personnel Microbiological - Personnel activityactivity

Microbiological ValidationGeneral Considerations 1 Biological systems

biological variability imprecision of methods low levels of contamination

Stressed / damaged organisms

Microbiological ValidationGeneral Considerations 2

Growth requirements of organisms require universal growth media TSA + Sabs Dex

Sequential temperature monitoring vs use of multiple media

Microbiological ValidationGeneral Considerations 3

Incubation times

5-7 days

but must read after day 1

Recovery Rates for TSA and SAB platesCherwell plates (irradiated)

Exposed for 3 hours in dispensary

0

10

20

30

40

50

60

0 1 2 3 4 5 6 7

Incubation Time - Days

cfu

TSA 32oC SAB 25oC

Microbiological ValidationGeneral Considerations 3 Incubation times

5-7 days but must read after day 1

Incubation temperatures Bacteria - 30-32oC Fungi 20-25oC

Microbiological ValidationGeneral Considerations 4 Sterile media

Aseptically prepared plates Pre-incubation

Irradiated plates less risk of false positives growth characteristics altered

Fertility assessment

Microbiological ValidationGeneral Considerations 5

Viable but non-culturable organisms (VBNC) Presence of non-recoverable organisms

Results are Retrospective Prospective release Retrospective release

Interpretation of Results

Facilities management Investigational threshold (Alert limits) Action limit

Counts ID of Organisms

source of organism consequences of contamination presence of new organisms failure of control measures

Trend analysis 1

Identify progressive and gross changes

variables

Workspace

Room

Product

Operator (not just aseptic processing)

Operator – spraying in

Trend Analysis 2

Methods available visualisation by charting and graphical methods statistical analysis population study software exception reporting

follow up of problems limitation of variables number of exceptions (investigational or action limits)

used as a measure of cleanliness

Microbiological Environmental Methods Random Methods

Settle plates

Contact sampling

Finger dabs

Organised Methods Active air sampling

*Assumptions**Assumptions*

Settle Plates

method of collection sampling area sampling time positioning

trend analysis representative sample

laminar air flow consideration 0o, 45o and 90o

Surface Counts

methods Rodac Plates Swabs Proprietary systems

sampling area and location pickup efficiency neutralisation post sampling removal of media application pressure validation of disinfection processes

Finger Dabs

sampling technique

what does it assess?

holes in gloves

poor transfer disinfection

Active Air Sampling

methods impingement filtration

sampling efficiency - recovery rates particle size sampling method

disruption of air flow - isokinetic probes

quantitative comparison accessibility sensitivity

Sterility Testing Ideal test? - product Test lacks sensitivity Retest only available under certain

conditions Prospective vs retrospective Appropriate levels of control SAL of testing process

Broth Transfer Testing 1 Process transfer tests

worst case scenario >batch size x3 initially 6 monthly repeat

Operator transfer tests Universal Broth Transfer Test Adapted operator tests or process tests

Broth Transfer Tests 2

Ideal test? - QA of process

Statistical considerations to reach AQL

1 in 1000

or 1 in 10,000

Frequency?

Sensitivity - do we challenge the test?

Conclusions Microbiological validation indicates

personnel involvement All microbiological validation

methods have limitations Microbiological validation methods

cannot be used in isolation and should be used holistically to gain a true picture of product assurance

The future Where does the validation cult go?

Next stage is validating the validation

Next stage to that is validating the validation of the primary validation and so on……….