Sterile Processing and Manufacturing of Sterile Products PDF

Transcript Sterile Processing and Manufacturing of Sterile Products Slide 1: Introduction............................................................................................................ 2 Slide 2: The Requirement for Sterility....................................................

Transcript Sterile Processing and Manufacturing of Sterile Products Slide 1: Introduction............................................................................................................ 2 Slide 2: The Requirement for Sterility................................................................................ 3 Slide 3: Defining Sterility and Sterilisation......................................................................... 4 Slide 4: Sterilisation Methods Used in Pharmaceutical Manufacturing.......................... 5 Tab 1: Thermal: Moist and Dry Heat................................................................................ 6 Tab 2: Radiation................................................................................................................ 8 Tab 3: Gas.......................................................................................................................... 9 Tab 4: Filtration............................................................................................................... 10 Slide 5: Sterilisation Kinetics............................................................................................ 11 Slide 6: Sterilisation Kinetics and Parameters K, D, Z and F......................................... 12 Tab 1: K-value: The Death Rate Constant..................................................................... 12 Tab 2: D-value: Decimal Reduction Time....................................................................... 13 Tab 3: Z-value Graph....................................................................................................... 14 Tab 4: F-value.................................................................................................................. 14 Slide 7: Sterilisation Kinetics: Sterility Assurance Level................................................. 15 Slide 8: Sterility Test and Associated Problems.............................................................. 16 Slide 9: Validation.............................................................................................................. 17 Slide 10: Monitoring and Validation: Biological and Physical Indicators......................... 18 Tab 1: Physical Indicators in Sterilisation Cycles.......................................................... 19 Tab 2: Biological Indicators in Sterilisation Cycles........................................................ 20 Slide 11: Aseptic Processing: Cleanrooms......................................................................... 21 Tab 1: Cleanrooms.......................................................................................................... 22 Slide 12: Cleanroom Design and Operation....................................................................... 23 Tab 1: Airflow................................................................................................................... 24 Tab 2: Personnel............................................................................................................. 25 Tab 3: General Cleanroom Design and Processes........................................................ 25 Slide 13: Aseptic Processing: Media Fill Studies............................................................... 26 Slide 14: Production of Sterile Products: Some Other Relevant Tests............................. 27 Slide 15: Summary............................................................................................................... 28 1  Transcript Slide 1: Introduction Hello there and welcome to this presentation on the session about sterile processing and manufacture of sterile products. My name is Deirdre D’Arcy, and in this session, we will cover an introduction to the kinetics of sterilisation and to sterilisation methods. We will describe thermal sterilisation, which includes moist and dry heat sterilisation, radiation sterilisation, gas sterilisation and filtration through a bacteria-retentive filter, and also aseptic processing. We will cover some aspects of validation, monitoring and testing of sterile products. Although aseptic production is not a terminal sterilisation process, it is a method of producing a sterile product, so we will also discuss it here. It is important to note that wherever possible a product should be terminally sterilised - that is, the product sterilised in its final container. 2  Transcript Slide 2: The Requirement for Sterility What types of pharmaceutical products are required to be sterile, and why? Injectable products or parenteral products, which include small volume parenterals and large volume parenterals such as infusions, are required to be sterile. Ophthalmic products are also required to be sterile. Products like parenteral and ophthalmic products, which are not terminally sterilised or are produced by aseptic processing, are very, very high-risk products. Parenteral products essentially bypass the defences produced by the body’s membranes, and with respect to the eye ophthalmic products are being delivered to an extremely delicate and sensitive surface which can be damaged by infection. There are also some other formulation types which are not always sterile but should be sterile for some specific uses, for example medicated foams when used on large open wounds. In the European Pharmacopoeia, the general monographs on formulated preparations do indicate which ones need to be sterile. If your product is not sterile, it can result in a contaminated product being given to a vulnerable patient, which can result in sepsis and/or death. Furthermore, contamination can result in product spoilage. 3  Transcript Slide 3: Defining Sterility and Sterilisation So, first of all, let's think about the term sterility, what is sterility, what does sterility mean? Sterility has been defined as the absence of viable microorganisms, and in this brief sentence, absence of viable microorganisms, there's actually a lot of meaning. What is a viable microorganism and how can we show that there is an absence of viable microorganisms? First of all, we can consider that something is sterile resulting from sterilisation. Sterilisation is the process by which all life forms are removed or destroyed. Remember, we're thinking about viable life forms and viable life forms are those which form progeny. So, for example, if a cell is not in a vegetative state, if you've got a spore, that doesn't mean it's dead, it can still turn into a cell which is growing and reproducing. In other words, once it can form progeny, it's a viable life form, a viable microorganism. Consequently, if sterilisation is the process by which all life forms are removed or destroyed, the question is how do we remove or destroy them? And how do we prove that this is done? It's very difficult to absolutely prove that something is sterile. If you consider a process by which you might sample a product, then culture your sample to demonstrate nothing is growing in it -that process could actually result in contamination of your sample during the sampling process. So, it's very difficult to prove that something is sterile, we will get back to that later. 4  Transcript Slide 4: Sterilisation Methods Used in Pharmaceutical Manufacturing There are different sterilisation methods listed in the pharmacopoeia, which states that one or more of these methods may be used to achieve sterilisation. Furthermore, modifications to, or combinations of these methods may be used provided there is sufficient process validation and product suitability. The pharmacopoeial methods listed are thermal methods including steam (moist heat) sterilisation and dry heat sterilisation, ionising radiation sterilisation; gas (vapour phase) sterilisation and membrane filtration. As mentioned, aseptic processing is not a sterilisation method but is an approach used to produce a sterile product. We will this discuss this in more detail later in the presentation. There is guidance available in the Study section on the appropriate choice of sterilising agent for different product types. So, what are these recommended sterilisation methods, and how do they work? Click each tab to learn more. When you ready, click next to continue. 5  Transcript Tab 1: Thermal: Moist and Dry Heat Thermal sterilisation methods include moist and dry heat sterilisation methods, where heat is the sterilising agent. Moist Heat Sterilisation is usually carried out in a pressurised chamber called an autoclave. The autoclave includes a source of steam so that the product loaded within the autoclave is exposed to dry, saturated steam for an appropriate length of time. When considering the method of action of moist heat sterilisation, it is important to remember the contribution from sensible and latent heat. Sensible heat relates to the energy required to bring the water temperature to boiling point, latent heat is the energy required for the phase change from water to steam. When steam condenses, it releases latent heat. The latent heat contributes hugely to the lethality of moist heat sterilisation, therefore it is essential that the sterilising chamber is filled with dry, saturated steam to ensure product exposure to both sensible and latent heat. For this reason, pressure is also critical. Image(s): 1. Pharmaceutical Practice Winfield and Richards 3rd ed pg 128 Churchill Livingstone 6  Transcript Tab 1.1: Thermal: Moist and Dry Heat Related to moist heat sterilisation is steam-in-place, (following clean-in-place) where pipework and equipment used in the manufacturing process are exposed to steam in a purpose-designed set-up. This contributes to disinfection of surfaces used in manufacturing which might otherwise be dismantled and sterilised separately for example in an autoclave. Using steam-in-place can avoid or minimise manual aseptic dismantling and reassembly for cleaning and sterilisation of equipment. Tab 1.2: Thermal: Moist and Dry Heat Dry heat sterilisation is carried out in an oven-like chamber which ensures that chamber design and product loading facilitate good heat circulation to maintain uniform heat throughout the chamber. Pharmacopoeial reference conditions are 2 hours at 160 degrees C. 7  Transcript It is mainly used for sterilising non-aqueous products. Tab 2: Radiation Radiation sterilisation includes both gamma irradiation and electron beam irradiation. Gamma irradiation, usually from a cobalt 60 source, is carried out in a purpose-built facility, requiring safe housing of equipment and operator protection. Radiation dose is monitored using dosimeters, and terminal sterilisation is possible once loading patterns are validated. Electron-beam or e-beam sterilisation is another form of radiation sterilisation. E-beam radiation consisting of β particles, generated mechanically for example by Van de Graaf or microwave linear accelerators, which can be switched off when not in use. Radiation sterilisation can be used for medical devices. Radiation sterilisation can affect the properties of some packaging materials. Therefore, it must be established that product packaging is compatible with this sterilisation method. 8  Transcript Tab 3: Gas Gas sterilisation is not usually used for terminal product sterilisation. It is carried out in a pressurised chamber similar to an autoclave. Ethylene oxide is the most common agent used for gas sterilisation. Another application of gas sterilisation is use of vapour phase hydrogen peroxide to sterilise workstations, for example isolators, used in aseptic processing. Therefore, although not terminal sterilisation of a final product, this is a useful application of gas sterilisation in sterile product production. Tab 3.1: Gas Ethylene oxide is a very effective sterilising agent but has many disadvantages including flammability and toxicity risks. Sterilisation efficacy is affected by many factors including 9  Transcript gas concentration, relative humidity, and temperature. Therefore, many aspects need to be monitored during sterilisation. Furthermore, post-sterilisation a degassing period is required to ensure toxic residues are below safe limits. Tab 4: Filtration Filtration sterilisation involves removal of micro-organisms through a bacteria retentive filter. It is used for sterilising heat-sensitive liquids which cannot be autoclaved or sterilised by other sterilisation methods. Filtration is very common at many stages of sterile product manufacture, and at a certain point of the production process a filter will be the designated “sterile” barrier, beyond which the filtrate is considered sterile, and this is the designated sterilising filter. Filtration sterilisation must be carried out under aseptic conditions by skilled operators. 10  Transcript Slide 5: Sterilisation Kinetics Now, let us consider sterilisation kinetics. Firstly, it is important to note that because heat or thermal sterilisation is probably the most common sterilising agent, sterilisation kinetics are usually explained as relevant to heat sterilisation, moist heat sterilisation in particular. Considering thermal sterilisation as an example, a homogenous population of organisms do not all die at the same time. Instead, there is usually a constant proportion of the surviving organisms killed during each increment of time. So, for example, if you start off with one million microorganisms in a product and if you know that 90 percent are killed in two minutes, after the first two minutes you will have reduced your number from one million to 100,000. After the next two minutes, you will reduce by a further 90 percent of that one hundred thousand down to 10,000. And after the next two minutes, you'll be down to one thousand and so on. That's an exponential decrease in survival numbers due to the exponential nature of the microbial death process. A graph of log 10 percent survivors versus time, or a graph of % survivors on a log scale vs time, should be linear. And we can see an example of such a graph here, we've got a log of present survivors versus time and we have a nice linear plot. However, sterilisation kinetics also apply to gas, and radiation sterilisation methods. If we have gas sterilisation, then you're also looking at time exposed to the gas, though it's a little bit more complex with concentration, humidity and temperature also affecting the effect of the exposure time. For radiation sterilisation, it's not time exposed to various sources it’s the total absorbed dose that’s considered, because you have decay in the source of your radioactivity and therefore the time isn't a constant in terms of the exposure to radiation source. Therefore, the sterilisation kinetics apply to the cumulative dose. With filtration sterilisation it's completely different. There isn't necessarily an exponential decrease over time because the filter isn't destroying microorganisms; it’s removing them. 11  Transcript Image(s) 1. Aulton’s Pharmaceutics 1st Edition Slide 6: Sterilisation Kinetics and Parameters K, D, Z and F We can determine several kinetic parameters from graphs of microbial survival vs time and related measurements when studying sterilisation kinetics, Click each tab to learn more. When you are ready, click next to continue. Tab 1: K-value: The Death Rate Constant K-value: The Death Rate Constant If you plot log natural % survivors vs. time, the slope is minus k, where k is the death rate 12  Transcript constant. Do note whether a plot uses natural log (Ln) or log to the base 10 (Log10). Tab 2: D-value: Decimal Reduction Time D-value: decimal Reduction Time We have D, which is the decimal reduction time. This is the time it takes in minutes, at a defined temperature, to destroy 90 percent of the viable microorganisms. Destroying 90 percent of the viable microorganisms is reducing the number by one log cycle. The D - value is the reciprocal of the death rate constant (k) in this plot of log precent organisms versus time. So that's why when we talk about the decimal reduction time as time in minutes, we need to define the temperature of the measurement because with respect to heat sterilisation, a change in temperature will often affect the time it takes to kill 90 percent of your microorganisms. And the temperature at which your D-value is measured is given a subscript. For example, D subscript one hundred and twenty-one degrees. So, if you plot the Log percent survivors or the % survivors on a log scale versus time, you can work out what time it takes to reduce your survivor numbers by one log cycle. 13  Transcript Tab 3: Z-value Graph Z-value Graph The Z value relates to the heat resistance of a micro-organism. The Z value is the number of degrees of temperature change required to produce a 10-fold change in D value. So, for example, if at one temperature it took 25 minutes to reduce the population by one log cycle or by 90 percent, you might think twenty-five minutes is too long. I'd rather two point five minutes. How much would you need to increase your temperature by to reduce that time from twenty-five minutes to two point five minutes? In this graph we see log D- value plotted against temperature. Using plots like these we can see what change in temperature is required to change the D-value by 1 log cycle. Tab 4: F-value 14  Transcript F-value F is a measure of the total lethality. This equates the heat treatment at one temperature with time in minutes at a designated reference temperature that would be required to produce the same lethality in an organism of the stated Z value. For a temperature of 121 degrees and an organism with a Z value of 10 degrees, the value becomes F zero. This is with respect to moist sterilisation because one hundred and twenty-one degrees is the reference temperature in moist heat sterilisation. So, for example, you could have an F value of eight, and that would mean the total heat treatment with a new cycle is the equivalent of eight minutes of exposure to your reference temperature in your reference cycle. Image(s): 1. Aulton’s Pharmaceutics 1st Edition 2. Aulton’s Pharmaceutics 1st Edition 3. Aulton’s Pharmaceutics 3rd edition 3rd ed. Pg. 227 Slide 7: Sterilisation Kinetics: Sterility Assurance Level In considering microbial inactivation we considered the D-value or the time in minutes to reduce the population by one log cycle so you can go from one million to one hundred thousand to ten thousand to one thousand to one hundred to ten to one micro-organism. What happens if you keep going? You can't have one tenth of a micro-organism surviving and one hundredth of microorganisms surviving. What happens is you get into what's called an area of calculated risk. You get into an area of probability. So, after your sterilisation cycle suggests that you should have 10 microorganisms surviving, then one microorganism surviving after another period of the time it takes to reduce by one log cycle, you then have the probability of one microorganism in 10 surviving. And then one in one hundred and one in one thousand probability. So, it's a one in 10 probability of a microorganism surviving or, for example, one in 10 probability of having a contaminated product, one in one hundred probability of microbial survival. One in 1000 probability of 15  Transcript microbial survival and so on. Then we can get to this concept, which is called the sterility assurance level, the sterility assurance level is the degree of assurance with which the process in question renders the population of items sterile. So, for example, a sterility assurance level or SAL of 10 to the power of minus six denotes a probability of not more than one viable microorganism in one million sterilised items of final product. So, when we discussed or considered the definition of sterile, which was the absence of viable microorganisms because of this exponential decrease in microbial survival numbers, we cannot definitively say when we get to zero microorganisms, we just get into a lower and lower and lower probability of a microorganism surviving as we increase the time exposed to a sterilisation process. This again highlights the difficulty of proving that a product is sterile. Therefore, we can use a sterility assurance level as our target assurance that a product is sterile, and a sterility assurance level or SAL of one in one million can be deemed acceptable. Image(s): 1. Aulton’s Pharmaceutics 1st Edition Slide 8: Sterility Test and Associated Problems What about sterility testing? Why can't we just test our products to see if they're sterile? Well, there is a sterility test as part of end product testing. It is mandatory in many cases. A sterility test essentially involves taking samples from a selection of products in your product batch, in their final containers, and culturing that sample in specified media and conditions to ascertain whether there was any microbial contamination in the sample. However, there are quite a few problems with the sterility test. There is the possibility of false positives because you can contaminate your sample while you're sampling it in order to culture it to determine if there are any survivors. 16  Transcript And you can have false negatives because the sample you take might simply not be the part of your product which has the contaminating microorganisms in it. The sterility test is based on the assumption that any contamination will be homogenous throughout the batch whereas you might not have homogenous contamination. Because it's a destructive test you can't just test every product, therefore you need a very well-designed sampling plan. Furthermore, you might have very low levels of contamination in combination with non- homogenous contamination. Therefore, it's possible that you take a sample which does not contain microorganisms that might be there in your product. Moreover, even if you do take a sample and, in that sample, you do include microorganisms which are present and which are contaminating your product, they might not actually recover in the culture medium that you're using for contaminant detection in the sterility test, and the contamination would thus remain undetected. So, there are many challenges around sterility testing, but there isn't any other end- product test. Therefore, in the case of terminally sterilised products, physical proofs which are biologically based and automatically documented, which showed the correct treatment throughout the batch during sterilisation are of greater assurance than the sterility test. And that statement comes from the Pharmacopoeia in the guidelines for using the test for sterility. There is a link to the Pharmacopoeia guidelines for using the test for sterility in the Extend section of your session homepage. Slide 9: Validation And so that brings us to validation. Validation is the act of proving a process works. It is crucial in sterile products due to the high-risk nature of the products and the shortcomings of end-product testing in terms of the sterility test. 17  Transcript With a validated sterilisation cycle and then continuous monitoring we can have a very high degree of assurance that we are sterilising our product and a greater assurance, in fact, than we would get from sterility testing alone. In some cases, a product can be granted parametric release, which means the sterility testing is waived based on the amount of validation and ongoing monitoring that is undertaken. As mentioned, validation is the act of proving a process works. To prove a process works, you need to a) understand the process to define the process b) define what is expected of the process (what is meant by “works”?) and c) generate proof -usually taken to be automatically generated documentation. When validating you must understand the critical processes and conditions of your process, and in addition to cycle validation, you must ensure that these critical process conditions are routinely monitored and recorded, to show that all parts of your product load have achieved the required conditions (to attain your accepted sterility assurance level) during sterilisation. Slide 10: Monitoring and Validation: Biological and Physical Indicators In terms of validation and monitoring, there's more information on these topics in the module. The relevant physical conditions in each sterilisation process must be monitored, for example, temperature and pressure in moist heat sterilisation, all relevant process parameters including temperature, humidity and gas concentration for gas sterilisation, and dosimeters can monitor absorbed dose for radiation sterilisation. Filtration sterilisation also requires filter integrity testing -which is a non-destructive test and is used to verify that the filter pore size is acceptable and is the same before and after use. 18  Transcript In addition to monitoring and recording the physical conditions, you can have physical indicators to indicate that parameters have been met, and biological indicators which correlate the physical conditions with biological effect. Click each tab to learn more. When you are ready, click next to continue. Tab 1: Physical Indicators in Sterilisation Cycles If a substance has a certain melting point it will melt when it reaches that temperature, but that only indicates the temperature is reached. It doesn't indicate that it's been reached for a certain period of time, and you must have the temperature reached for an adequate exposure time for effective sterilisation. Chemically-based physical indicators can be used to prove parameters have been met. You can use, for example, Brownes tubes, where you've got a chemical within the tubes that starts off red and goes to green, if it's been exposed to the correct temperature for the correct time. There are various different indicators that are used as appropriate to different types of sterilisation cycles. Image(s) 1.“BROWNE GREEN SPOT TUBE.” STERIS Animal Health, www.sterisanimalhealth.co.uk/shop/product/browne-green-spot-tube/. 19  Transcript Tab 2: Biological Indicators in Sterilisation Cycles In addition to physical indicators there are also biological indicators which are really important in validation of sterilisation cycles; biological indicators are usually spores of micro-organisms that have a very high resistance compared to your natural bio-burden. They're not very pathogenic spores. They just have a high natural resistance to the sterilising agent they are being exposed to. And they're very well defined in terms of the quality and characteristics of the microorganisms. So, they have to be a certain identified strain of certain species with a certain D-value, with very clear culturing requirements, and they must be easy to cultivate so it is possible to actually identify survivors from the biological indicators after exposure to a sterilisation process. You can establish the killing kinetics from these biological indicators in your process quite easily. You can culture the biological indicators after being exposed to your sterilisation process for varying lengths of time to see what survivor numbers are, and from this you can establish, or verify, the killing kinetics of your sterilisation process. Biological indicators correlate the physical properties of the sterilisation cycle with the biological effect. They are used in cycle validation for all methods except radiation sterilisation where they are not always used. In gas sterilisation they are used in sterilisation cycle validation and routine cycle monitoring. In filtration sterilisation the equivalent is a microbial challenge test, which doesn’t assess killing kinetics but rather the ability of a filter to retain a defined amount and species of micro-organism. The microbial challenge test is a destructive test. 20  Transcript Slide 11: Aseptic Processing: Cleanrooms As I stated earlier, aseptic processing isn't a terminal sterilisation method, but it is a method of producing a sterile product. An aseptic process can be defined as: A process performed maintaining the sterility of a product that is assembled from components, each of which has been sterilised by steam, dry heat, ionizing radiation, gas, or sterile filtration. This is achieved by using conditions and facilities designed to prevent microbiological contaminants. (EMA Guideline on the sterilisation of the medicinal product, active substance, excipient and primary container; EMA/CHMP/CVMP/QWP/BWP/850374/2015. Additionally, when producing products which will be terminally sterilised, it is very important to control the environment in which they are produced. So, that brings us on to talking about clean rooms. What is a clean room? A cleanroom has been defined as- A room designed, maintained, and controlled to prevent particle and microbiological contamination of drug products. Such a room is assigned and reproducibly meets an appropriate air cleanliness classification (FDA Guidance for industry: Sterile Drug Products Produced by Aseptic Processing — Current Good Manufacturing Practice FDA 2004). Click the tab to learn more. When you are ready, click next to continue. 21  Transcript Tab 1: Cleanrooms Products are compounded and made in clean rooms before being terminally sterilised. and cleanrooms must be used in aseptic processing when there is no final terminal sterilisation step. Clean rooms are designed to minimise microbial and particulate contamination. You can have introduction of contamination into a clean room or generation of contamination in the clean room. For example, you could have particulate contamination generated in the cleanroom from particles coming off the bench in the clean room. There are different grades of cleanroom and the grades are defined by the microbial and particulate contamination levels which are permissible in each grade of clean room. Tab 1.1: Cleanrooms 22  Transcript There are different types of workstations in the cleanroom for example, a laminar airflow cabinet or an isolator cabinet. Although a laminar airflow cabinet has air sweeping through the cabinet from the filter, the laminar airflow cabinet is open to the outside environment, so the environment that the cabinet is in must be very clean. An isolator on the other hand, as the name would suggest, is completely sealed where the operator works through gloves or gauntlets. Products are placed into a transfer hatch, which can then be used to transfer products into the clean room and out of the clean room. So, the isolator can be placed in a lower grade of clean room than a laminar airflow cabinet. You can have positive or negative pressure within the isolator. The isolator and the gloves must be tested for integrity to ensure that there is no breach in the integrity of the isolator. Reference(s): 1. EMA Guideline on the sterilisation of the medicinal product, active substance, excipient and primary container; EMA/CHMP/CVMP/QWP/BWP/850374/2015 2. (FDA Guidance for industry: Sterile Drug Products Produced by Aseptic Processing — Current Good Manufacturing Practice FDA 2004 Image(s): 1. Winfield and Richards, chapter 13, page 14 and 142 2. Winfield and Richards, chapter 13, page 14 and 142 3. Winfield and Richards, chapter 13, page 14 and 142 Slide 12: Cleanroom Design and Operation 23  Transcript The following are important considerations in clean room design and operation: Click each tab to learn more. When you are ready, click next to continue. Tab 1: Airflow Personnel and the air supply to the clean room are the greatest sources of contamination introduced to the clean room. It should have filtered air continuously sweeping the room. Pressure differentials should be present between different grades of clean room with the highest pressure in the cleanest grade, so that air will move from your cleaner grade to your less clean grade. Tab 1.1: Airflow You have usually got a HEPA (high efficiency particulate air) filter delivering air into the 24  Transcript cleanroom. The air can be uni-directional or non-uni directional. Image(s): 1. Winfield and Richards Tab 2: Personnel Along with air supply to the cleanroom, consider the personnel in your clean room as the greatest source of contamination introduced to the clean room. Your personnel must be properly trained and authorised and wearing purpose-made or appropriate cleanroom clothing or cleanroom garb. Tab 3: General Cleanroom Design and Processes Separation of different grades of clean room areas is enabled through a positive 25  Transcript pressure differential from the cleanest to the dirtiest clean room, with appropriate doors and access points through the cleanrooms. The clean room must be properly designed so that it is easy to clean and won't harbour any particles or contamination. You must have a good cleaning and disinfection protocol and all of the processes, from the cleaning and monitoring to the actual manufacturing that's undertaken in the clean room, all must be designed to minimise contamination. There is a link to particulate and microbial standards in the cleanroom in the Study section of your session homepage. Slide 13: Aseptic Processing: Media Fill Studies A media fill is the performance of an aseptic manufacturing procedure using a sterile microbiological growth medium in place of the product. Instead of manufacturing the product, you use nutrient growth medium in place of the product, which is usually done multiple times, for example, three times for the whole process. Media fill studies are used to validate aseptic processing or essentially the whole process of manufacturing a sterile product in a clean room. All of the worst-case scenario events that could happen during routine production should be realistically replicated during a media fill study. The media fill study should include anything that might happen during a batch run, a shift change, preventive maintenance and so on. For the media fill study to be successful, nothing should be growing in the growth media used in the media fill study, after exposing the growth media to all of these process events and parameters. 26  Transcript Slide 14: Production of Sterile Products: Some Other Relevant Tests In terms of tests relevant to sterile products, we have already discussed the sterility test which is culturing samples of a product to find out if there is microbial contamination. Other tests which are important include tests relating to the environmental monitoring of your clean rooms whether it's for products which will be terminally sterilised or products which will which are undergoing a septic processing. You need to monitor particulate and microbial contamination of the clean room. You also have testing for visible and subvisible particulate contamination of sterile products. Particulate contamination may not necessarily be contamination with a viable particle or a microorganism, but you want to avoid particulate contamination anyway. Also, there is pyrogen or bacterial endotoxin testing. Pyrogen testing is core to production of water for injections, which is used a lot in the manufacture of sterile products. 27  Transcript Slide 15: Summary After completing this session, and engaging with the related learning material provided, you should be able to: Describe official sterilisation methods and aseptic production processes, and Explain sterilisation monitoring and validation approaches and the requirement for sterility. 28