General
1. This chapter applies to active substances or intermediates thereof manufactured by cell culture or fermentation using natural or recombinant organisms.
2. This Chapter applies as from the point at which a vial of the cell bank is retrieved for use in the manufacturing of an active substance or intermediates thereof.
3. For active substances or intermediates manufactured by means of cell culture or fermentation, the control of bioburden, viral contamination and endotoxins during the manufacture as well as monitoring of the process at appropriate stages may be necessary depending on the source, method of preparation and the intended use of the active substance or intermediate thereof.
4. Appropriate equipment and environmental controls shall be used to minimise the risk of contamination. The acceptance criteria for environmental quality and the frequency of monitoring shall depend on the step in the production and the production conditions (open, closed or contained systems).
5. Process controls shall take into account:
(a)
maintenance of the working cell bank, where appropriate;
(b)
proper inoculation and expansion of the culture;
(c)
control of the critical operating parameters during fermentation or cell culture;
(d)
monitoring of the process for cell growth, viability (for most cell culture processes) and productivity, where appropriate;
(e)
harvest and purification procedures that remove cells, cellular debris and media components while protecting the active substances or intermediates thereof from contamination (particularly of a microbiological nature) and from loss of quality;
(f)
monitoring of bioburden and, where needed, endotoxin levels at appropriate stages of production;
(g)
viral safety concerns as described in the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q5A Guideline ( 8 ) , where appropriate.
6. Where appropriate, the removal of media components, host cell proteins, other process-related impurities, product-related impurities or contaminants shall be demonstrated.
Cell bank maintenance and record keeping
1. Access to cell banks shall be limited to authorised personnel.
2. Cell banks shall be maintained under storage conditions designed to maintain cell viability and prevent contamination. The international guideline ICH Q5A Guideline shall be taken into account.
3. Records of the use of the vials from the cell banks and storage conditions shall be maintained.
4. Where appropriate, cell banks shall be periodically monitored to determine suitability for use.
Cell culture or fermentation
1. Where aseptic addition of cell substrates, media, buffers and gases is needed, closed or contained systems shall be used where possible. If the inoculation of the initial vessel or subsequent transfers or additions (media, buffers) are performed in open vessels, there shall be controls and procedures in place to minimise the risk of contamination.
2. Where the quality of the active substance can be affected by microbial contamination, manipulations using open vessels shall be performed in a biosafety cabinet or similarly controlled environment.
3. Personnel shall be appropriately gowned and take special precautions handling the cultures.
4. Critical operating parameters (e.g. temperature, pH, agitation rates, addition of gases, pressure) shall be monitored to ensure compliance with the established process. Cell growth, viability (for most cell culture processes), and where appropriate, productivity shall also be monitored. Critical parameters will vary from one process to another, and for classical fermentation, certain parameters (e.g. cell viability) may not need to be monitored.
5. Cell culture equipment shall be cleaned and sterilised after use. As appropriate, fermentation equipment shall be cleaned and sanitised or sterilised.
6. Culture media shall be sterilised before use where appropriate to protect the quality of the active substance.
7. Appropriate procedures shall be in place to detect contamination and to determine the course of action to be taken. Those procedures shall include instructions on how to determine the impact of the contamination on the product and to decontaminate the equipment and return it to a condition to be used in subsequent batches. Foreign organisms observed during fermentation processes shall be identified as appropriate and the effect of their presence on product quality shall be assessed, if necessary. The results of those assessments shall be taken into consideration in the disposition of the material produced.
8. Records of contamination events shall be maintained.
9. Use of shared (multi-product) equipment shall be based on a risk assessment and may warrant additional testing after cleaning between product campaigns, as appropriate, to prevent the risk of cross-contamination.
Harvesting, isolation and purification
1. Harvesting steps, either to remove cells or cellular components or to collect cellular components after disruption, shall be performed in equipment and areas designed to minimise the risk of contamination.
2. Harvest and purification procedures to remove or inactivate the producing organism, cellular debris and media components (while minimising degradation, contamination, and loss of quality) shall be adequate to ensure that the intermediate or active substance is recovered with consistent quality.
3. All equipment shall be properly cleaned and, as appropriate, sanitised after use. Multiple successive batching without cleaning may be used if intermediate or active substance quality is not compromised.
4. If open systems are used, purification shall be performed under environmental conditions appropriate for ensuring product quality.
5. Additional controls, such as the use of dedicated chromatography resins or additional testing, may be appropriate if equipment is to be used for multiple products. Introduction of those methods is subject to risk assessment.
Viral removal and inactivation steps
1. Viral removal and viral inactivation steps shall be performed within their validated parameters.
2. Appropriate precautions shall be taken to prevent potential viral contamination from pre-viral to post-viral removal or inactivation steps. Open processing shall be performed in areas that are separate from other processing activities and have separate air handling unit.
3. The same equipment shall normally not be used for different purification steps. In those cases where the same equipment is used, the equipment shall be appropriately cleaned and sanitised before re-use.
4. Appropriate precautions shall be taken to prevent potential virus carry-over (e.g. through equipment or environment) from previous steps.
Source: EUR-Lex (Publications Office of the EU), © European Union, reuse permitted under Commission Decision 2011/833/EU.
