Patent Publication Number: US-2023151319-A1

Title: Bacteriostatic filter system for antibody drugs production process, and method of operating same

Description:
TECHNICAL FIELD 
     The present invention relates to a sterilization filter system for a process of manufacturing an antibody pharmaceutical and an operation method thereof. 
     BACKGROUND ART 
     Biopharmaceuticals can be broadly classified into new biologics, improved biopharmaceuticals (biobetters) and biosimilars, and compared with chemically synthesized pharmaceuticals, have fewer side effects and less preclinical data required in research and development, and are easier to predict product efficacy and safety and due to the relatively high probability of clinical success, active development of technology is progressing worldwide. 
     The process of manufacturing biopharmaceuticals consists of initial candidate material and cell line development, a culture process (upstream processing (USP)), a purification process (downstream processing (DSP)), and a fill and finish process, and particularly, in the case of biosimilar product production, processing optimization in the culture process (USP) and purification process (DSP) is directly related to cost competitiveness, so interest in optimizing the process of manufacturing biosimilars with low cost, high purity and high yield is growing. 
     In this process, the culture process (USP) corresponds to the process of continuously increasing the number of cells through cell division for approximately 6 weeks from the initial flask stage of less than 1 liter to the final production bioreactor stage of 15,000 L or more, after thawing the cell line, and culture methods that can be used herein include batch culture, fed-batch culture, continuous culture, and perfusion culture and the like. 
     In addition, the purification process (DSP) is the process of extracting a protein to be used as a pharmaceutical with high purity and high efficiency from the culture in which the cells and cell debris are mixed through the manipulation and use of various types of chromatographs and filters, and during the DSP, column purification, virus removal and ultra/diafiltration are performed through the use of a chromatograph and filters. 
     Meanwhile, components and systems used in the USP and DSP are divided into stainless steel (SS) and single-use (SU) using disposable bags or tubes in terms of material, and among these, although the SS process system including device components made of SS has advantages of easy implementation on a relatively large scale, low operation cost and easy automation, the initial installation cost is high, it is vulnerable to contamination and prone to the downstream bottleneck phenomenon occurring in the DSP, caused by the implementation of a large-sized bioreactor. 
     The SU process system, which has recently been introduced, uses disposable bags or tubes with a volume of 0.1 to 2,000 L as device components, and compared to the SS process system, has advantages of relatively low cost for initial installation and being relatively resistant to contamination because a corresponding part can be replaced upon contamination. However, scale-up limitations, continuously-incurring operation costs caused by frequent bag replacement and the input of a lot of labor during equipment replacement are pointed out as disadvantages. 
     In the field of biopharma today, there are more and more companies serving as contract manufacturing organizations (CMOs) for clinical trials and drugs for commercial use, and furthermore, improvement in one-stop service from cell line development and related process development, scale-up to commercial production is also made. 
     Meanwhile, in purification and culture processes, a medium, which is a nutrient mixture for cell culture and microbial culture, and a buffer used to stably extract a protein as a liquid buffer and acidity regulator are used, respectively, and the medium and buffer are used after a sterilization process. 
     The sterilization process is performed by a sterilization filter, EU GMP requires a filter integrity test before and after an aseptic process using a sterilization filter, and when there is a problem with the sterilization filter, contaminants cannot be properly filtered, so it is essential to perform a filter integrity test before/after the use of the sterilization filter. 
     Meanwhile, conventionally, to test the integrity of a sterilization filter, the integrity of the sterilization filter was checked by removing the entire housing containing the filter, performing a test in a separate location, and then returning the housing to its original position. In this case, depending on the number of transfers of a medium, a buffer and a process liquid, the aforementioned procedure was repeated several times and requires manual operation, so there were problems of excessive input of labor and delayed process time. 
     DISCLOSURE 
     Technical Problem 
     In view of the aforementioned problems, the present invention is directed to providing a sterilization filter system for a process of manufacturing an antibody pharmaceutical, which is able to reduce the time required for filter cartridge exchange and an integrity test and automate the transfer or reverse transfer of a medium and a buffer and the transfer or reverse transfer of a process liquid, leading to decreases in labor and process time, by designing the configuration of components and the system to arrange a sterilization filter cartridge in an in-line manner, perform a sterilization filter integrity test in situ by a control unit, and transfer a medium or buffer from a preparation tank to a storage tank or reversely transfer the medium or buffer transferred to the storage tank to the preparation tank, depending on an integrity test result value, unlike the related art in which the integrity of the sterilization filter was checked by removing the entire housing containing the filter, performing a test in a separate location, and then returning the housing to its original position. 
     In addition, technological problems to be solved in the present invention are not limited to the above-described technical problems, and other problems which are not described herein will be fully understood by those of ordinary skill in the art from the following descriptions. 
     Technical Solution 
     The present specification provides a sterilization filter system for a process of manufacturing an antibody pharmaceutical, which includes: a preparation tank for preparing one selected from a medium and a buffer; a storage tank for storing the medium or buffer received from the preparation tank; a transfer pipeline configured to flow the medium or buffer stream discharged from the preparation tank into the storage tank; a process liquid storage tank for storing a process liquid in the intermediate stage of purification and culture processes; a process liquid transfer pipeline configured to flow the process liquid into the process liquid storage tank; a sterilization filter cartridge disposed on one or more selected from the transfer pipeline and the process liquid transfer pipeline; and a control unit, wherein the sterilization filter cartridge includes, for a washing and filter test process including one or more selected from filter sterilization, filter wetting, flushing, filter integrity test, air ballasting and barrier integrity testing, a first pipeline entering the sterilization filter cartridge and a second pipeline exiting the sterilization filter cartridge. 
     In the present specification, the sterilization filter system for a process of manufacturing an antibody pharmaceutical further includes an integrity tester on the first pipeline entering the sterilization filter cartridge. 
     In the present specification, in the sterilization filter system for a process of manufacturing an antibody pharmaceutical, the control unit automatically transfers a medium or buffer from the preparation tank to the storage tank or reversely transfers the medium or buffer transferred to the storage tank to the preparation tank, depending on a filter integrity test result value. 
     In addition, in the present specification, the control unit automatically transfers the process liquid to the process liquid storage tank or reversely transfers the process liquid transferred to the process liquid storage tank along the process liquid transfer pipeline, depending on a filter integrity test result value. 
     In addition, in the present specification, the sterilization filter system is applied to transfer one or more of a medium, a buffer and a process liquid in the process of manufacturing one or more antibody pharmaceuticals selected from the group consisting of abagovomab, abciximab, adalimumab, adecatumumab, alemtuzumab, altumomab, altumomab pentetate, anatumomab, anatumomab mafenatox, arcitumomab, atlizumab, basiliximab, bectumomab, ectumomab, belimumab, benralizumab, bevacizumab, brentuximab, canakinumab, capromab, capromab pendetide, catumaxomab, certolizumab, clivatuzumab tetraxetan, daclizumab, denosumab, eculizumab, edrecolomab, efalizumab, etaracizumab, ertumaxomab, fanolesomab, fontolizumab, gemtuzumab, girentuximab, golimumab, ibritumomab, igovomab, infliximab, ipilimumab, labetuzumab, mepolizumab, muromonab, muromonab-CD3, natalizumab, necitumumab, nimotuzumab, ofatumumab, omalizumab, oregovomab, palivizumab, panitumumab, ranibizumab, rituximab, satumomab, sulesomab, ibritumomab, ibritumomab tiuxetan, tocilizumab, tositumomab, trastuzumab, ustekinumab, visilizumab, votumumab, zalutumumab, brodalumab, anrukinzumab, bapineuzumab, dalotuzumab, demcizumab, ganitumab, inotuzumab, mavrilimumab, moxetumomab pasudotox, rilotumumab, sifalimumab, tanezumab, tralokinumab, tremelimumab, urelumab, adornase alfa, Rebif, becaplermin, alteplase, laronidase, alefacept, aflibercept, raxibacumab, darbepoetin alfa, becaplermin concentrate, interferon beta-1b, botulinum toxin type A, rasburicase, asparaginase, epoetin alfa, etanercept, agalsidase beta, interferon alfacon-1, interferon alfa-2a, anakinra, botulinum toxin type B, pegfilgrastim, oprelvekin, filgrastim, denileukin diftitox, peginterferon alfa-2a, aldesleukin, dornase alfa, interferon beta-1a, becaplermin, reteplase, interferon alfa-2, tenecteplase, drotrecogin alfa, rilonacept, romiplostim, methoxypolyethylene glycol-epoetin beta, a C1 esterase inhibitor, idursulfase, alglucosidase alfa, abatacept, galsulfase, palifermin and interferon gamma-1b. 
     In addition, the present specification provides a method of operating the sterilization filter system, which includes sequentially performing filter sterilization, filter wetting, flushing, a first filter integrity test, air ballasting and a barrier integrity test, transferring one or more selected from a medium, a buffer and a process liquid using an automatic valve, and following the completion of the transfer of one or more selected from a medium, a buffer and a process liquid, sequentially performing filter wetting, flushing, a second filter integrity test using an automatic valve, along the first pipeline, the filter cartridge and the second pipeline. 
     In addition, in the present specification, the filter integrity test includes one or more tests selected from a forward flow integrity test (FFIT), a bubble point test (BPT), and a pressure hold test (PHT). 
     In addition, in the present specification, the control unit automatically transfers a medium or a buffer from the preparation tank to the storage tank when the first filter integrity test result value satisfies a preset reference value, and sends a sterilization filter replacement alarm when the first filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the present specification, the control unit continues the washing and filter test process when the second filter integrity test result value satisfies a preset reference value, and reversely transfers the medium or buffer transferred to the storage tank to the preparation tank when the second filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the present specification, the control unit automatically transfers a process liquid to the process liquid storage tank along the process liquid transfer pipeline when the first filter integrity test result value satisfies a preset reference value, and sends a sterilization filter replacement alarm when the first filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the present specification, the control unit continues the washing and filter test process when the second filter integrity test result value satisfies a preset reference value, and reversely transfers the process liquid transferred to the process liquid storage tank along the process liquid transfer pipeline when the second filter integrity test result value does not satisfy the preset reference value. 
     Advantageous Effects 
     A sterilization filter system and operation method according to the present invention can reduce the time for filter cartridge exchange and integrity testing by designing the configuration of components and the system to arrange a sterilization filter cartridge in an in-line manner, perform a sterilization filter integrity test in situ by a control unit, and transfer a medium or buffer from a preparation tank to a storage tank or reversely transfer the medium or buffer transferred to the storage tank to the preparation tank, depending on an integrity test result value, unlike the related art in which the integrity of the sterilization filter was checked by removing the entire housing containing the filter, performing a test in a separate location, and then returning the housing to its original position. 
     In addition, the sterilization filter system and operation method according to the present invention can reduce labor and process time by implementing a system that automates the transfer and reverse transfer of a medium and a buffer using a control unit, and further the transfer and reverse transfer of a process liquid. 
     Accordingly, in the manufacture of antibody pharmaceuticals, when the sterilization filter system is adopted, process costs and efficiency can be improved, and a smart factory can be more effectively implemented. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG.  1    schematically shows a sterilization filter system for a process of manufacturing an antibody pharmaceutical, implemented according to one embodiment of the present invention. 
         FIG.  2    shows a flowchart of a method of operating a sterilization filter system for a process of manufacturing an antibody pharmaceutical according to one embodiment of the present invention. 
     
    
    
     MODES OF THE INVENTION 
     The terms used in the specification are used only to describe specific examples, not to limit the present invention. Singular expressions include plural expressions unless clearly indicated otherwise in the context. It should be understood that the term “comprise,” “include,” or “have” used herein is for indicating the presence of implemented characteristics, numbers, steps, elements or a combination thereof, and does not preclude the possibility of the presence or addition of one or more other characteristics, numbers, steps, elements or a combination thereof. 
     In addition, in the present invention, when a layer or element is referred to as being formed “on” or “over” each layer or element, it is meant that each layer or element is formed directly on each layer or element, or another layer or element is formed on each layer, or that another layer or element may additionally be formed between layers, on an object, or a substrate. 
     The present invention may have various modifications and various examples, and thus specific examples are illustrated in the drawings and described in detail in the detailed description. However, it should be understood that the present invention is not limited to specific embodiments, and includes all modifications, equivalents or alternatives within the spirit and technical scope of the present invention. 
     In addition, in the present invention, the term “unit” used throughout the specification and claims may mean a software or hardware component, and the “unit” performs a certain role. However, the “unit” is not limited to software or hardware. The “unit” may be configured to be present in an addressable storage medium or to regenerate one or more processors. Therefore, in one example, the “unit” includes components such as software components, object-oriented software components, class components and task components, processors, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuit, data, database, data structures, tables, arrays, and variables. The functions provided in the components and “units” may be combined into a smaller number of components and “units”, or further separated into additional components and “units.” 
     According to one embodiment of the present invention, the “unit” may be implemented as a processor and a memory. The term “processor” should be construed broadly to include a general-purpose processor, a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a controller, a microcontroller, and a state machine. In some circumstances, the “processor” may refer to an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). The term “processor” may also refer to a combination of processing devices, for example, a combination of DSP and a microprocessor, a combination of a plurality of microprocessors, a combination of one or more microprocessors combined with a DSP core, or a combination of random components. 
     The term “memory” should be construed broadly to include any electron component that can store electron information. The term “memory” may also refer to various types of processor-readable media such as a random access memory (RAM), a read-only memory (ROM), a non-volatile random access memory (NVRAM), a programmable read-only memory (PROM), an erase-programmable read-only memory (EPROM), an electrically erasable PROM (EEPROM), a flash memory, magnetic or optical data storage devices, and registers. A memory is said to be in electronic communication with the processor if the processor is capable of reading information from and/or writing information to the memory. The memory integrated in the processor is in electronic communication with the processor. 
     Hereinafter, a sterilization filter system for a process of manufacturing an antibody pharmaceutical and an operating method thereof according to exemplary embodiments of the present invention will be described in further detail. 
     Sterilization Filter System for Process of Manufacturing Antibody Pharmaceutical 
     A sterilization filter system for a process for manufacturing an antibody pharmaceutical according to one embodiment of the present invention includes a preparation tank for preparing one selected from a medium and a buffer; a storage tank for storing the medium or buffer received from the preparation tank; a transfer pipeline configured to flow the medium or buffer stream discharged from the preparation tank into the storage tank; a process liquid storage tank for storing a process liquid in the intermediate stage of purification and culture processes; a process liquid transfer pipeline configured to flow the process liquid into the process liquid storage tank; a sterilization filter cartridge disposed on one or more selected from the transfer pipeline and the process liquid transfer pipeline; and a control unit, wherein the sterilization filter cartridge may include, for a washing and filter test process including one or more selected from filter sterilization, filter wetting, flushing, filter integrity test, air ballasting and barrier integrity testing, a first pipeline entering the sterilization filter cartridge and a second pipeline exiting the sterilization filter cartridge (see  FIG.  1   ). 
     Meanwhile, in one embodiment of the present invention, a medium preparation tank of the preparation tank may be connected with a medium storage tank, and a buffer preparation tank of the preparation tank, and the buffer preparation tank of the preparation tank may be connected with a buffer storage tank. 
     In further detail, the process of manufacturing an antibody pharmaceutical consists of initial candidate material and cell line development, a culture process (USP), a purification process (DSP), and a fill and finish process. 
     In this process, the culture process (USP) corresponds to the process of continuously increasing the number of cells through cell division for approximately 6 weeks from the initial flask stage of less than 1 liter to the final production bioreactor stage of 15,000 L or more, after thawing the cell line. 
     The cultivation unit according to one embodiment of the present invention is a set of components for the culture process, which may include a medium preparation tank for preparing a medium in advance, a medium storage tank for receiving the media from the medium preparation tank and storing the medium, a feed line through which a feed stream including thawed cells and a culture medium is introduced into a bioreactor, one or more bioreactors including a stirring system, which receive the thawed cells and the medium from the feed stream and increase the number of cells through cell division, and a discharge line which discharges the medium containing the cells cultured in the bioreactor as an effluent stream. 
     In addition, the purification unit according to one embodiment of the present invention is a set of components for the purification process (DSP), which may include a buffer preparation tank for preparing a buffer in advance, a buffer storage tank for receiving the buffer from the buffer preparation tank and storing the buffer, a chromatograph for removing impurities mixed in the medium using the medium received from the cultivation unit and the buffer transferred from the buffer storage tank to increase the purity of a target protein, and one or more filtration systems which are disposed before or after the chromatograph to perform buffer exchange and concentration. 
     In addition, in an intermediate procedure of the culture and purification processes, a process liquid storage tank for storing a process liquid and a process liquid transfer pipeline configured to introduce the process liquid into the process liquid storage tank may be further included. 
     Meanwhile, the preparation tank and storage tank for one selected from a medium and a buffer, and the medium, buffer or process liquid transfer pipeline may be formed of one or more materials selected from an SS material and an SU disposable bag, or may be hybrid systems formed of a mixture thereof. 
     Meanwhile, in purification and culture processes, a medium, which is a nutrient mixture for cell culture and microbial culture, and a buffer used to stably extract a protein as a liquid buffer and acidity regulator are used, respectively, and the medium and buffer are used after a sterilization process. 
     The sterilization process is performed by a sterilization filter, EU GMP requires a filter integrity test before and after an aseptic process using a sterilization filter, and when there is a problem with the sterilization filter, contaminants cannot be properly filtered, so it is essential to perform a filter integrity test before/after the use of the sterilization filter. 
     Meanwhile, conventionally, to test the integrity of a sterilization filter, the integrity of the sterilization filter was checked by removing the entire housing containing the filter, performing a test in a separate location, and then returning the housing to its original position. In this case, depending on the number of transfers of a medium, a buffer and a process liquid, the aforementioned procedure was repeated several times and requires manual operation, so there were problems of excessive input of labor and delayed process time. 
     The present inventors confirmed that, unlike the related art in which the integrity of the sterilization filter was checked by removing the entire housing containing the filter, performing a test in a separate location, and then returning the housing to its original position, when the configuration of components and a system are designed to arrange a sterilization filter cartridge in an in-line manner, perform a sterilization filter integrity test in situ by a control unit, and transfer a medium or buffer from a preparation tank to a storage tank or reversely transfer the medium or buffer transferred to the storage tank to the preparation tank, depending on an integrity test result value, the system that can reduce the time required for filter cartridge exchange and an integrity test and automate the transfer or reverse transfer of a medium and a buffer and the transfer or reverse transfer of a process liquid, leading to decreases in labor and process time, and thus completed the present invention. 
     Specifically, according to one embodiment of the present invention, the sterilization filter cartridge including a sterilization filter may include a first pipeline which is disposed on one or more lines selected from the medium or buffer feed pipeline and the process liquid transfer pipeline and introduced into the sterilization filter cartridge and a second pipeline exiting the sterilization filter cartridge for a washing and filter test process including one or more selected from filter sterilization, filter wetting, flushing, filter integrity test, air ballasting and barrier integrity testing. 
     In the present invention, as described above, by installing the sterilization filter cartridge on the feed pipeline and/or the process liquid transfer pipeline in an in-line manner, labor for the attachment/detachment and movement of the filter cartridge, and process time are reduced. 
     In addition, an integrity tester may be provided on the first pipeline entering the sterilization filter cartridge (see  FIG.  1   ). 
     The filter integrity tester is a component for performing physical, non-destructive testing for investigating whether there are defects in a filter membrane in order to prevent the leakage of contaminants due to the damage or defect in the filter or the failure of the original function of the filter, and one or more tests selected from a forward flow integrity test (FFIT), a bubble point test (BPT) and a pressure hold test (PHT) may be performed using the aforementioned component. 
     Specifically, the FFIT test is also referred to a diffusion test, which is based on a principle that compressed air or nitrogen gas passes through a liquid filling the pores of the filter by diffusion when pressure is applied with a differential pressure of a bubble point or less. Meanwhile, the BPT test is a test based on a principle that a liquid is contained in the pores of a filter by surface tension and capillary force, and the BPT test measures the minimum pressure required to push a liquid out of the pores of the membrane filter by exceeding the surface tension and the capillary force. Meanwhile, the PHT test is also referred to a pressure decay or pressure drop test, which is a method of monitoring a pressure change at the upper part of a filter due to diffusion or leakage of a gas passing through the filter, and uses a very precise pressure gauge. 
     Meanwhile, different from the feed pipeline and/or the process liquid transfer pipeline, the first pipeline entering the sterilization filter cartridge and the second pipeline exiting the sterilization filter cartridge are configured to perform a process such as wetting or air ballasting, and clean and oil-free air (COA) may be introduced into the sterilization filter cartridge or discharged out of the cartridge along the first or second pipeline, respectively. 
     Meanwhile, the in-line sterilization filter cartridge according to one embodiment of the present invention may undergo a washing and filter test processes including one or more selected from filter sterilization, filter wetting, flushing, filter integrity test, air ballasting and barrier integrity testing, and the specific order of processes performed and which processes are specifically included may be differently selected before and after transfer of one selected from a medium, a buffer and a process liquid. 
     In one example, referring to  FIG.  1   , in the culture process, filter sterilization, filter wetting, flushing, a first filter integrity test, air ballasting and a barrier integrity test may be sequentially performed using an automatic valve before medium transfer, and filter wetting, flushing and a second filter integrity test may be sequentially performed using an automatic valve after medium transfer, which is possible to design and change appropriately. 
     Meanwhile, the transfer of a medium, a buffer and a process liquid and the washing and filter test may be controlled by a control unit, and the control unit may be a component configured to automatically transfer a medium or buffer from the preparation tank to a storage tank or reverse-transfer the medium or buffer transferred to the storage tank to a preparation tank by comparing a filter integrity test result value with the preset reference value (reference). 
     In addition, the control unit may be a component configured to automatically transfer the process liquid to the process liquid storage tank or reverse-transfer the process liquid transferred to the process liquid storage tank along the process liquid transfer pipeline by comparing the filter integrity test result value with the preset reference value (reference). 
     Specifically, the control unit may include one or more components selected from a processor and a memory, and the process may execute instructions stored in the memory. Meanwhile, the processor may include, for example, a central processing unit (CPU), a graphics processing device (GPU) or both, and in one example, may be of a type in which the process operation is automated (adjusted and controlled) by the processor and the memory in the control unit. In one example, the control unit according to one embodiment of the present invention may be a programmable logic controller (PLC). 
     Meanwhile, the sterilization filter system according to one embodiment of the present invention may be applied to transfer one or more of a medium, a buffer and a process liquid in the process of manufacturing one or more antibody pharmaceuticals selected from the group consisting of abagovomab, abciximab, adalimumab, adecatumumab, alemtuzumab, altumomab, altumomab pentetate, anatumomab, anatumomab mafenatox, arcitumomab, atlizumab, basiliximab, bectumomab, ectumomab, belimumab, benralizumab, bevacizumab, brentuximab, canakinumab, capromab, capromab pendetide, catumaxomab, certolizumab, clivatuzumab tetraxetan, daclizumab, denosumab, eculizumab, edrecolomab, efalizumab, etaracizumab, ertumaxomab, fanolesomab, fontolizumab, gemtuzumab, girentuximab, golimumab, ibritumomab, igovomab, infliximab, ipilimumab, labetuzumab, mepolizumab, muromonab, muromonab-CD3, natalizumab, necitumumab, nimotuzumab, ofatumumab, omalizumab, oregovomab, palivizumab, panitumumab, ranibizumab, rituximab, satumomab, sulesomab, ibritumomab, ibritumomab tiuxetan, tocilizumab, tositumomab, trastuzumab, ustekinumab, visilizumab, votumumab, zalutumumab, brodalumab, anrukinzumab, bapineuzumab, dalotuzumab, demcizumab, ganitumab, inotuzumab, mavrilimumab, moxetumomab pasudotox, rilotumumab, sifalimumab, tanezumab, tralokinumab, tremelimumab, urelumab, adornase alfa, Rebif, becaplerm in, alteplase, laronidase, alefacept, aflibercept, raxibacumab, darbepoetin alfa, becaplermin concentrate, interferon beta-1b, botulinum toxin type A, rasburicase, asparaginase, epoetin alfa, etanercept, agalsidase beta, interferon alfacon-1, interferon alfa-2a, anakinra, botulinum toxin type B, pegfilgrastim, oprelvekin, filgrastim, denileukin diftitox, peginterferon alfa-2a, aldesleukin, dornase alfa, interferon beta-1a, becaplermin, reteplase, interferon alfa-2, tenecteplase, drotrecogin alfa, rilonacept, romiplostim, methoxypolyethylene glycol-epoetin beta, a C1 esterase inhibitor, idursulfase, alglucosidase alfa, abatacept, galsulfase, palifermin and interferon gamma-1b, and may be variously applied throughout a process of manufacturing antibody pharmaceuticals, such as biopharmaceuticals, improved biopharmaceuticals (biobetters) and biosimilars. 
     Method of Operating Sterilization Filter System for Process of Manufacturing Antibody Pharmaceutical 
     Meanwhile, the method of operating a sterilization filter system according to one embodiment of the present invention may include sequentially performing filter sterilization, filter wetting, flushing, a first filter integrity test, air ballasting and a barrier integrity test, transferring one or more selected from a medium, a buffer and a process liquid using an automatic valve, and following the completion of the transfer of one or more selected from a medium, a buffer and a process liquid, sequentially performing filter wetting, flushing, a second filter integrity test using an automatic valve, along the first pipeline, the filter cartridge and the second pipeline (see  FIG.  2   ). 
     Meanwhile, it should be understood that the terms “first” and “second” used throughout the specification and claims of the present invention are intended to arbitrarily determine an order. 
     Meanwhile, the filter integrity test may include one or more tests selected from a forward flow integrity test (FFIT), a bubble point test (BPT) and a pressure hold test (PHT), and a specific test method is as described above. 
     Meanwhile, in the method of operating a sterilization filter system according to one embodiment of the present invention, the control unit may automatically transfer a medium or a buffer from the preparation tank to the storage tank when the first filter integrity test result value satisfies a preset reference value, and send a sterilization filter replacement alarm when the first filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the method of operating a sterilization filter system according to another embodiment of the present invention, the control unit may continuously perform the washing and filter test process when the second filter integrity test result value satisfies a preset reference value, and reversely transfer the medium or buffer transferred to the storage tank to the preparation tank when the second filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the method of operating a sterilization filter system according to still another embodiment of the present invention, the control unit may automatically transfer a process liquid to the process liquid storage tank along the process liquid transfer pipeline when the first filter integrity test result value satisfies a preset reference value, and send a sterilization filter replacement alarm when the first filter integrity test result value does not satisfy the preset reference value. 
     In addition, in the method of operating a sterilization filter system according to yet another embodiment of the present invention, the control unit may continuously perform the washing and filter test process when the second filter integrity test result value satisfies a preset reference value, and reversely transfer the process liquid transferred to the process liquid storage tank along the process liquid transfer pipeline when the second filter integrity test result value does not satisfy the preset reference value. 
     In one example, when the control unit according to one embodiment of the present invention is a programmable logic controller (PLC), by using an in-line sterilization filter cartridge, a built-in integrity tester and an automatic valve, the required process is programmed and logicized in series, thereby performing an automated filter integrity test with the push of a button. 
     In one example, after the installation of a disposable sterilization filter cartridge in an SS housing before medium transfer, filter sterilization, filter wetting, flushing, a first filter integrity test using process COA, air ballasting and a barrier integrity test are sequentially performed in an in-line manner. Here, the control unit automatically transfers a medium from the preparation tank to the storage tank when the first filter integrity test result value satisfies a preset reference value, and sends a sterilization filter replacement alarm when the first filter integrity test result value does not satisfy the preset reference value. 
     After the completion of the medium transfer, the control unit sequentially performs filter wetting, flushing and a second filter integrity test using an automatic valve, and here, when the second filter integrity test result value satisfies the preset reference value, after replacing the filter cartridge for a subsequent process, the aforementioned washing and filter test process proceeds to a subsequent step to restart, and when the second filter integrity test result value does not satisfy the preset reference value, the medium transferred to the storage tank is reversely transferred to the preparation tank. 
     As described above, the control unit automates the transfer or reverse-transfer of a medium, a buffer and a process liquid by comparing the filter integrity test result value with the preset reference value, so an in-situ process can be performed directly on site without moving equipment for testing. 
     As described above, according to the sterilization filter system and operation method according to the present invention, the time for filter cartridge replacement and integrity testing may be reduced by designing the configuration of components and a system to arrange a sterilization filter cartridge in an in-line manner, perform a sterilization filter integrity test in situ by a control unit, and transfer a medium or buffer from a preparation tank to a storage tank or reversely transfer the medium or buffer transferred to the storage tank to the preparation tank, depending on an integrity test result value. 
     In addition, the sterilization filter system and operation method according to the present invention may implement a system automating the transfer and reverse-transfer of a medium and a buffer, and further the transfer and reverse-transfer of a process liquid using the control unit, thereby reducing labor and the process time. 
     Accordingly, in the manufacture of antibody pharmaceuticals, when the sterilization filter system is adopted, process costs and efficiency can be improved, and a smart factory can be more effectively implemented. 
     In the above, the present invention has been described with reference to exemplary embodiments, but the present invention is not limited to the described embodiments, and it is obvious to those skilled in the art or those of ordinary skill in the art that the present invention can be variously modified and changed without departing the spirit and scope of the present invention. Accordingly, such modifications or variations should not be individually understood from the technical spirit or point of view of the present invention, and the modified embodiments should belong to the claims of the present invention.