Gene Therapy Production Facility Considerations

1
Gene Therapy Production Facility Considerations

• Robert Sausville
• Center for Biologics Evaluation and Research
• Office of Compliance and
• Biologics Quality
• Division of Case Management

2

• Overview
• General Considerations
• Special Considerations
• Biosafety Levels
• Air Quality
• Environmental Monitoring
• Validation
• Qualification
• Miscellaneous

3
Overview

• New manufacturing areas
• retrofits of existing facilities
• located within existing facilities
• Designed to minimize potential for contamination
• between products
• between early and late stages of production
• Operations should be well controlled
• Personnel should be appropriately trained
• someone responsible for facility operations,
  equipment validation and maintenance, record
  keeping

4
General Considerations

• Good techniques and appropriate equipment used to
  minimize exposure to infectious agents
• Strict adherence to standard practices and
  techniques (consistent manufacture of product)
• Safety equipment (primary barrier)
• biological safety cabinet
• closed containers
• other designs to minimize aerosols
• Facility design (secondary barrier)
• amount of protection depends on the nature of the
  infectious agent and production associated risks
  (aerosols)

5
General Considerations cont.

• As the risk for aerosol transmission increases,
  higher levels of primary containment and multiple
  secondary barriers may become necessary

6
General Considerations cont.

• Facility designed for aseptic processing
• Smooth surfaces, seamless tile, etc.
• Hard, easily cleanable and impervious finishes
• Non shedding ceilings
• HEPA filtered air from seperate air handling unit
• separation of production from other areas of the
  facility (often a hospital)
• Phase 1/II
• Class 100,000 general manufacturing areas
  (10,000 III)
• Class 100 all open manipulations

7
General Considerations cont.

• Separate entrance/gowning area
• Air locks (containment)
• No personnel access between vector production and
  transduction areas
• Room(s) for support areas
• buffer media prep, glass/equipment wash
• Storage areas
• raw materials, cell banks
• adjacent to production if possible to minimize
  traffic in and out of the facility

8
General Considerations cont.

• Material and personnel flows designed to maximize
  efficiency and minimize mix-ups
• unidirectional flows where possible
• also controlled by procedures or temporally
• Emergency power for critical systems (UPS)

9
General Considerations Control of the Facility

• Production area(s) should be separate from other
  activities (research, testing)
• Potential cross-contamination should be minimized
• between process steps, and
• other production activities
• Access into the production area should be limited
• Equipment used in production should not be shared
  with non-production activities
• Environmental monitoring and product testing
  should be performed to ensure adequate control of
  the process/area
• Spill/accident procedures should be in place

10
Special Considerations Multi-use scenarios

• Concurrent vs. campaign production will impact
  design considerations
• Personnel work on one cell line at a time
• Procedures in place to prevent cross
  contamination
• Appropriate changeover procedures
• Adequate segregation of concurrent activities
• color coded labeling
• bar coded
• The sponsor is responsible for assuring that the
  contract manufacturer has all the procedures in
  place

11
Special Considerations Cont.

• Potential Routes of Cross Contamination
• Centrifuges (generation of aerosols)
• one sample processed at a time
• cleaning/sanitization of centrifuges between
  lots
• Pipettors
• effective cleaning procedures
• filters
• Incubators

12
Appropriate BioSafety Level

• In general, BioSafety Level 2
• Transduction
• Higher risk, BioSafety Level 3
• Vector Preparation
• Defined in CDC-NIH publication Biosafety in
  Microbiological and Biomedical Laboratories

13
BioSafety Level 2

• Transduction and non-viral vector preparation
• access limited
• personnel trained in handling pathogenic agents
• infectious wastes are decontaminated before
  disposal
• gowning required (lab coat, hair cover)
• gloves should also be worn for aseptic
  manipulations
• Class I or II Biosafety Cabinets to be used
• for procedures potentially creating aerosols
• aerosol generation should be minimized
• with high concentrations or large volumes of
  infectious agents

14
BioSafety Level 3

• Viral Vector prep areas, higher levels of
  containment
• Negative pressure or sink for containment
• All activities with infectious materials are
  conducted in biological safety cabinets
• Class I, II or III may be used
• Passage between two sets of doors is a basic
  requirement
• An autoclave for decontaminating waste is
  available
• preferably in the laboratory
• Ducted exhaust provided
• not recirculated
• may be discharged to the outside without being
  filtered

15
BioSafety Level 4

• Class III biosafety cabinets
• or personnel in suits with life support systems
• All materials must be autoclaved before leaving
  BSL4 area
• Exhaust air HEPA filtered

16
Air Quality

• Recommend that production areas receive single
  pass air (no recirculation) for vector production
• Dedicated air handler where possible
• Segregating air supply from rest of facility
  important, (hospital setting)
• HEPA-filtered air
• Objective to meet Class 100,000 specifications
  for Phase I/II
• In-line vs. terminal

17
Air Quality cont.

• Air pressure differentials between areas should
  be balanced to maintain cleanliness or
  containment
• Positive (aseptic processing)
• Negative (containment) for steps needing greater
  than BSL-2
• Open steps in biosafety cabinets (Class II)
• Quality monitored to assure facility is
  acceptable for production

18
Environmental Monitoring

• Testing of surfaces and for viable and non-viable
  particulates
• Demonstrate facility under control
• as part of validation
• routine monitoring program
• Frequency and intensity dependent on how close to
  GMPs the facility will operate
• specifications based on desired Class

19
Environmental Monitoring cont.

• Viable particulates
• active air monitoring devices (slit to agar,
  centrifugal samplers)
• settling plates (passive, less desirable)
• Non-viable particulates
• particle counters
• room classifications, certification of biosafety
  cabinets
• Surface contact plates or swabs
• monitor cleaning efficacy and personnel asepsis

20
NASA Standards Viable Air Particulates

• Room classification, defined by Federal Standard
  209E, determined by non-viable particulate
  monitoring under dynamic conditions.
• Class 100,000
• 2.5 CFU/ ft3
• Class 10,000
• 0.5 CFU/ ft3
• Class 100
• 0.1 CFU/ ft3

21
Settling Plates Exposure times

• Class 100,000
• 1 CFU/ 9cm plate
• 0.11 hours
• 2 CFU/ 9cm plate
• 0.21 hours
• 1 CFU/ 14cm plate
• 0.04 hours
• 2 CFU/ 14 cm plate
• 0.09 hours

• Class 100
• 1 CFU/ 9cm plate
• 2.65 hours
• 2 CFU/ 9 cm plate
• 5.31 hours
• 1 CFU/ 14 cm plate
• 1.10 hours
• 2 CFU/ 14 cm plate
• 2.21 hours

22
Validation

• Establishing documented evidence which provides
  a high degree of assurance that a specific
  process will consistently produce a product
  meeting its predetermined specifications and
  quality attributes.

23
Validation

• Sliding Scale approach for clinical
  manufacturing
• Facilities involved in clinical manufacturing
  should be in compliance with the concepts of
  cGMPs
• Do not expect full validation in early stages
  (may not have 3 repetitive runs, worst case
  configuration, etc.)
• facility supplying clinical material to other
  institutions implies that it meets cGMPs and
  should approach what is expected for commercial
  facilities
• Phase 3 material should be manufactured at close
  to full cGMP

24
Sliding Scale Approach, An Example

• Autoclave used to prepare sterile materials
• Early (I/II)
• demonstrate proper cycle achieved
• monitor temperature, pressure, and time
• use of biological indicators for verification
• loads not well defined

25
Autoclave cont.

• Middle (II/III)
• temperature mapping done to determine cold/hot
  spots
• biological indicators placed to verify cycle at
  problems points
• loads are somewhat defined

26
Autoclave cont.

• Late (III)
• lethality of cycle determined at monitored points
• loads are well defined and standardized
• each load configuration has been mapped or
  worst-case load has been validated
• Another example
• Sanitizer effectiveness
• Phase I/II supported by literature
• Phase III supported by validation

27
Process Validation

• Sterilization
• Decontamination
• Aseptic Processing
• Cleaning
• Inactivation/removal of adventitious agents and
  other contaminants

28
Equipment Qualification

• Program in place to demonstrate that equipment
  operates as expected
• Should include periodic monitoring

29
Equipment cont.

• Air handlers
• Biological safety cabinets
• pressures
• filter integrity
• airflows velocities
• leak testing

30
Equipment cont.

• Incubators
• uniform temperature
• carbon dioxide
• filters
• Centrifuges
• speed
• vacuum (ultras)
• temperature

31
Equipment cont.

• Autoclaves
• temperature
• pressure
• kill cycle
• Lyophilizers
• shelf temperature
• vacuum

32
Raw Materials

• Critical raw materials - established criteria for
  acceptance from vendors
• sterility
• adventitious agents
• activity/purity
• Vendors Certificate of Analysis
• identity test where possible
• Inventory Control
• proper storage
• FIFO

33
Water

• Should meet Water for Injection (WFI)
  specifications
• microbial lt10 CFU/100ml
• endotoxin lt0.25 EU/ml
• chemical tests per USP
• WFI for all product contact surfaces and
  formulations
• May be purchased

34
Personnel

• Designated person in charge of facility
• Responsible for
• limiting access
• training
• maintenance/safe operations
• writing and enforcing procedures
• Production personnel are trained (periodic
  retraining)
• Appropriately gowned for production step

35
Final Thoughts

• Design facility for worst-case maximum
  flexibility
• Consider filing a Master File for facilities
  handling several IND products
• Meet with FDA to discuss your Phase I/II (or
  III!) facility