PHCT 401 Aseptic Processes & Techniques Principles of Aseptic Techniques Aseptic Processing Sterility Testing Laminar flow air cleaning Quality Control Tests Personnel
PHCT 401
Aseptic Processes & Techniques
Principles of Aseptic Techniques
Aseptic Processing
Sterility Testing
Laminar flow air cleaning
Quality Control Tests
Personnel
Principles of Aseptic Techniques
Overview
• Certain pharmaceutical products must be sterile
• Parenteral preparation o Injections
o Intravenous infusions
o Non-injectable sterile fluids Urological (bladder) irrigation solutions
Peritoneal dialysis & Haemodialysis solutions
• Ophthalmic preparations o Eye drops/Oint
o Eye lotions
o Contact lens solution
• Dressings
• Implants
• Two categories of sterile products
Terminally Sterilized (TS) – can be sterilized in
their final containers
Non-Terminally Sterilized (NTS) – cannot / will
not be sterilized in their final containers.
Principle
‘Starting with sterile materials and equipments, it
is possible to produce a sterile product if strict
precautions are taken to avoid microbial
contamination’
• Methods used, collectively described as “Aseptic Technique”
• Aseptic manufacturing procedures available for different types of products.
• Awareness of aseptic handling procedures to be adopted to minimize risk of product contamination.
• Those who have cause to open, use or dispense sterile products e.g Hospital Pcy
• Manufacturing under conditions that do not permit entry of contaminating µorganisms
Aseptic Manufacturing Processing
Asepsis
“A state of control attained by using an
aseptic work area and performing activities
in a manner that precludes microbiological
contamination of the exposed sterile
product”
Aseptic Processing
“the processing of drug components (drug,
containers, excipients etc.) in a manner that
precludes microbiological contamination of
the final sealed product”
Aseptic processing:
“A method of producing sterile products in which sterile bulk product or sterile raw materials are compounded and filled into sterile containers in a controlled environment, in which the air supply, materials, equipment and personnel are regulated to control microbial and particulate contamination to acceptable levels”
• Objective is to maintain the sterility of a product, assembled from sterile components
• Operating conditions so as to prevent microbial contamination.
• Combination of various simple techniques and processes.
• Spoilage of medicines due to microbial
contamination is undesirable
• Various consequences
Financial loss – main
Risk of initiating infection (though uncommon)?
More important in terms of
oRisk to the patient
oPossible loss of life
Financial implications of product-related infections
Additional treatment costs
Product recalls
Possible litigation & damage to reputation
Understanding Aseptic processes & techniques
• Understand various sources of contaminating microorganisms in the production or work area
Personnel o Skin and respiratory tract flora
oMicrobial transfer from operators
Atmosphere - air
Water
Raw materials
Packaging materials
Equipment
Buildings oWalls & ceilings
o Floors &drains
o Doors, windows & fittings
• Quality of pharmaceutical products refers to ‘fitness for purpose’
• Product should not only have the desired therapeutic properties
• Safe for administration by intended route
• Sterile products – free from microbes
• Others like oral preparations, need not be sterile
Free from indicator pathogens that can be contracted through the oral route
• Greater attention paid to quality of sterile product
• Reflects additional Quality assurance required
• In demonstrating quality, tests carried out to detect the absence of quality
• Sterility Test
o Sampling products at random
o Testing for presence of microorganisms
o Samples taken should be representative of the whole population –Sampling Technique
o Absence of microorganisms will only allow you to estimate the statistical probability that the batch sampled is sterile.
o All products should therefore be manufactured in a suitable environment
By procedure that minimizes the possibility of microbial contamination occurring
Building quality into the product
At the end of the manufacturing process, tests can be performed as additional measure, since
Quality is not inspected into the product
Application of Aseptic Techniques & Processes
Techniques designed to prevent accidental contamination of sterile materials & pure cultures from the environment during handling
• Pharmaceutical manufacturing
• Foods & cosmetics
• Pure cultures of microorganisms used in Pharmaceutical biotechnology
Recombinant human insulin
Production of immunological products- vaccines
Production of antibiotics
Careful handling to prevent accidental contamination of pure stock
Aseptic technique involve procedures such as:
• Use of sterile apparatus & materials at all
times
• Use of proper closures & containers
• Wrapping of apparatus for sterilization
• Flaming of necks of containers in Bunsen
burner flame
• Minimal exposure of materials during handling
• Spraying & swabbing of benches & work area
with a suitable disinfectant
• Washing & scrubbing of hands
Keeping the operator’s dirt and germs out of the sterile cleanroom environment and away from sensitive products and processes is the main objective of the sterile cleanroom suit
Automated Hand-Washing System
•Use of protective clothing-to keep all clothing
parts together
Carrying out operations within/under special handling
cabinets equipped with filtered air.
Wearing of protective clothing
• Clothing worn must be made from non-
shedding materials: terylene a suitable fabric
• Proper head gears/wears
• Rubber or plastic gloves
• Face masks to prevent the release of droplets
must be worn by operators in the aseptic
areas for production of especially NTSP
• Prevents airborne contamination of both
microbial and particulate matter.
• Clothing that are close fitting at the neck, wrist
and ankles more suitable
• Clothing should be used once a day
• Fresh headwear, overshoes and powder-free
gloves should be provided for each working
session.
Four Pillars of a robust Aseptic Processing
• Personnel Training &Monitoring
• Environmental Monitoring
• Facility Design HVAC Validation
• Process Simulation (Media Fills)
Sterility Testing
• Required for all sterile products
• Not overriding control to cover all short-
comings
• Adequate attention must be paid to every
stage in the production process
Adequate premises
Sterilizing equipment and process
Skilled and trained personnel etc
• Building quality into the product
• ST is actually the detection of the absence of
quality!
• Sterility does not detect all known living forms
• Official tests for sterility detects gross contamination
with most common organisms (including pathogens)
• Most probable contaminants limited to bacteria and
fungi.
• No test for viruses
• Difficulty in culturing viruses
Design of Sterility Tests
Critical considerations
Sampling – method should give the greatest
probability of picking up an infected unit within the
batch.
Batch
Container Unit
Volume of medium
Inhibitory substances in the product
Product should not affect the ability of the medium to
support growth.
Added product not > 10% of the volume of medium. B.P
Details from U.S.P.
Media – appropriate to support likely contaminant
Bacteria
Fungi – modified
Inactivation
Of preservatives
Any constituent with AMA activity
Inactivation aids recovery of contaminants
Inactivators
• Not inhibitory to growth promoting property of
medium
• Should not interfere with nutritive quality of the
medium
Methods of inactivation
• Dilution
• Inactivation by constituents
• Destruction or inactivation / antagonization by
addition of sterile inactivators.
• Physical removal by filtration.
Other critical consideration
• Controls
• Incubation conditions
• Interpretation of results
Controls
• Two major controls against which to check
conclusion from the test series.
• Negative Control
Sterility of the media used
Checked by including un-innoculated bottles from
the same batch as that used in the test
• Positive Control
Growth promoting properties of the batch
Inactivation of inhibitory substances in the product
Demonstrated by including an exact set with same
quantities of test substance (sample) in the same
volumes of the batch of test media
Reporting Sterility Testing Results
CODE SAMPLE NUTRIENT
MEDIUM
CONTROL
OREGANISM
EXPECTED
RESULT
ACTUAL
RESULT
AET Sample Thioglycolate No Organism - ve
ANT Sample Thioglycolate No Organism -ve
FGT Sample SDM No Organism - ve
AET PC No Sample Thioglycolate S. aureus + ve
ANT PC No Sample Thioglycolate Clostridium + ve
FGT PC No Sample SDM Candida + ve
AET NC No Sample Thioglycolate No Organism - ve
ANT NC No Sample Thioglycolate No Organism -ve
FGT NC No Sample SDM No Organism - ve
KEY
AET = Aerobic Test
ANT = Anaerobic Test
FGT = Fungal Test
PC = Positive Control
NC = Negative Control
Laminar Flow Air Cleaning
• Providing the environment for aseptic manufacturing
• Cleanrooms with specific requirements
• Two major types
• Differentiated by their method of ventilation.
Turbulently ventilated cleanrooms (‘nonunidirectional’)
Unidirectional flow cleanrooms (originally known as
‘laminar flow’
The unidirectional type of cleanroom uses very much more
air than the turbulently ventilated type,
Gives a superior cleanliness. w.
Non-unidirectional Airflow
Figure shows a turbulently
ventilated room receiving clean
filtered air through air diffuses in
the ceiling. This air mixes with the
room air and removes airborne
contamination through air extracts
at the bottom of the walls. The air
changes are normally equal to, or
greater than, 20 per hour, this
being much greater than that used
in ordinary rooms, such as in
offices. In this style of cleanroom,
the contamination generated by
people and machinery is mixed
and diluted with the supply air and
then removed.
Unidirectional Airflow The horizontal flow cleanroom uses the same filtration airflow technique as the downflow, except the air flows across the room from the supply wall to the return wall. One major limitation of the horizontal flow design is that the downstream contamination in the direction of airflow increases.
Steps in Aseptic Room Air Filter
• Air intake
• Pre-filtration
• Temperature regulation
• Humidification
• HEPA filtration
HEPA - High Efficiency Particulate Air filters
Can remove 99.97% of airborne
Air intake
• From environment – high up
• Away from polluted area of town & chimneys
Pre-filtration
• Through a pre-filter
• Set of coarse filters next to the air intake
• Removes large particles (≥5µm)
Temperature regulating/adjustment
• Regulates air temperature to ambient
• If too cold, heats up
Humidification
• Prepare air of required humidity
• Incoming air passed through system of fine atomized
spray of de-mineralized water
HEPA filtration
• Final filtration step
• Air forced through high efficiency air filters
• Removes 99.97% of airborne particles of 0.3µm size
• Particles 0.3µm size most difficult to filter
• Considered MPPS (Most Penetrating Particle Size)
Airflow Control
• Vertical laminar flow
Personnel
• High standards of personal hygiene
• Most common source of contaminants in
sterile drug products.
• Large numbers of microbes
• Healthy population known as reservoir of
many microbes.(pathogens)
• Shed numerous ‘viable’ & ‘non-viable’
particles into environment
• Free from communicable diseases & open
lesions on exposed body surfaces.
• Organisms carried on (larger) skin particles.
• Adherence to high standards of cleanliness
ensured by
Adequate hand-washing facilities
Protective garments – head gears,
gloves
Appropriate training of all staff before being
permitted to enter the Aseptic Manufacturing
area
Fundamental Training Topics
Principles of cGMP
Practice & theory of assigned task
Aseptic technique
Microbiology
Gowning proficiency – training, observation.
Specific SOPs covering aseptic
manufacturing area operations.
Laminar Flow Air Cleaning