Common Pitfalls During Implementation of a Cleaning Validation Program
清潔驗(yàn)證計(jì)劃實(shí)施過(guò)程中的常見(jiàn)錯(cuò)誤
BACKGROUND
背景
Since theinitial discussions on Cleaning Validation in the early 1990’s and even afterthe FDA Guidance was published in 1993, there has been a lot of confusionrelated to the application of the Cleaning Validation (CV) requirements in ourindustry.Some operations apply incorrect or ineffective approaches for theimplementation of a CV program due to misunderstanding the purpose ofvalidating cleaning procedures and/or taking an extremely conservative approachmaking for an impractical demand on resources.This article willcover some of the most common pitfalls/faults of a strategy for implementing aCV program.1, 2
When a sitedecides (or is asked by regulators) to start a cleaning validationactivity/program, their first thought is completing the effort quickly. Attimes that haste can lead to the development of protocols to complete the taskwithout proper planification and strategy development. This causes execution ofactivities which may not be adequate, nor have value added, and, in the end,the company can spend time in totally unnecessary tasks. A helpful initialstrategy is to develop a process flow for implementing the program.
Process flowincludes the development of matrices for equipment/cleaning procedurecombinations for those products being manufactured. It is acceptable to useproduct family grouping if applicable. This is a primary step to select thecombinations of equipment/cleaning procedures including a worst-case productfor each of the CV efforts defined by the CV protocols. For example, I workedat a facility with 2,000 drug product codes that were changing rathercontinuously. After developing these matrices, we came up with 16 combinationsto be challenged with a specific CV protocol.
In some cases,equipment grouping approaches may also be applied. For example, we can select apiece of equipment (ora bracket composed of several pieces) to bechallenged from a group of similar equipment when there are no differencesbetween them beyond the size.
The next step isto answer the question of which component of the product will be used as thetarget for quantification of residues. Please note that using the term“product” is incorrect when quantifying finished drug formulations.
Based on thisselection, work can start on finding the analytical methods to be able toquantify residue levels of these target components. To support this effort, theacceptable limits for the residues (also called Maximum Carryover or MACO) mustbe established so that the methods will be accurately quantify residue levelsbelow the limits.
Parallel to thedevelopment/validation/verification of the analytical methods, the equipmentcleaning procedures must be reviewed to determine if they are sufficientlydetailed, include all necessary critical parameters (times, temperatures,contact times, flows/pressures) and that personnel are properly trained ontheir execution. Especially for manual cleaning procedures, the accuracy andcompleteness of details on the documentation are critical for demonstratingconsistency and ensuring that the process can be considered “validated” foreach step. Remember, if a cleaning agent is used, then the cleaning agentresidues must also be considered for the development of an analytical methodfor testing those residues. The cleaning agent supplier can provide support inthis task.
The trainingprogram/process for the cleaning procedures must be reviewed and revised asnecessary to incorporate adequate levels of challenges and qualifications toproperly conduct the cleaning. In addition, approaches for the testing of dirtyand clean hold times needs to be established.
Once all ofthese steps are well on their way to execution, specific CV protocol(s) can beestablished where each document represents the challenges for anequipment/cleaning procedure combination with a worst-case product(s) alreadyselected.
2、Pre-requisites must be identified before starting the execution of a specificcleaning validation activity/protocol
在開(kāi)始執(zhí)行特定的清潔驗(yàn)證活動(dòng)/方案之前,必須確定先決條件
As stated above,the pre-requisites for the CV program must be established early and, inaddition, they must be verified, and such verification must be documentedwithin each CV protocol execution. The pre-requisites that must be verifiedwithin each CV protocol include:
Equipment design that is adequate for the applied cleaning procedure. For example, a CIP application will require certain conditions on the equipment design to be considered adequate. If a CIP system is installed permanently, was this system qualified? If a stand-alone CIP skid is used, the same question applies. The question in terms of the adequate design also applies to the CIP skid itself.
Analytical methods were validated/verified for the selected target components and the cleaning agent formula component (if applicable). The methods can quantify the target components with a limit of quantification which is lower than the limit for those residues. The equipment used in the laboratory are also qualified.
The cleaning procedure is adequate, has all the details and required parameters and the documentation will provide evidence that the procedure was followed as written.
Personnel were trained on the analytical methods, sample collection and the cleaning procedures as applicable.
對(duì)人員進(jìn)行了分析方法、取樣和清潔程序(如適用)的培訓(xùn)。
Calibrations of instruments used are current.
使用的儀器均已校準(zhǔn)。
3、CleaningValidation cannot be executed unless the procedures for cleaning are properlydetailed and/or are being documented
除非清潔程序足夠詳細(xì)和/或記錄,否則無(wú)法執(zhí)行清潔驗(yàn)證
In my extensiveyears of assessing cleaning processes and cleaning validation efforts, I haveseen plenty of company representatives that do not understand the criticalityof assuring an adequate cleaning procedure is implemented before a CV activitycan start. In nearly every case such as this, the cleaning procedures needed tobe revised. It is critical to understand how the cleaning steps,conditions/parameters, documentation were developed. In most cases, companiesjust apply a cleaning process that they are familiar with no program fordevelopment of the cleaning process. In one occasion, a company was usingmineral oil as a “cleaning agent”. When asked to dismantle the recirculationlines from the mixing tanks, various residues came out as the lines had neverbeen dismantled for cleaning. Fortunately, as of late more companies arestarting to understand the importance of such efforts, though likely afterspending lots of time/resources trying to validate a cleaning procedure thatwas not well defined. Some critical decisions in defining the cleaningprocedures are:
Is the cleaning done manually? If so, the procedure needs to be reviewed with a focus to ensure people will follow the steps consistently.
清潔是否人工完成？如果是這樣,需要重點(diǎn)審查程序，以確保人員可以一致地遵循這些步驟。
If the cleaning is executed by an automated system, such as a CIP skid or permanently installed system? In this case the procedure needs to be reviewed from a different perspective including the operation of the system and the data to be collected/reviewed. Sometimes this equipment includes on-line measurement of TIOC and/or conductivity which can be used to monitor the cleaning process continuously.
4、CleaningValidation is executed as a product-specific challenge
為每一個(gè)產(chǎn)品進(jìn)行清潔驗(yàn)證挑戰(zhàn)
Many companiesstill conduct a cleaning validation strategy by conducting a CV study/protocolfor each product. This is feasible in cases where there are just a few productsbut, more often it can be rather impractical (and nearly impossible) to conducta CV study for each product. This is one of the main reasons to work on astrategy/plan early (see step 1 above) before starting any activity. Ask thequestion: – do we have to conduct a cleaning validation protocol for eachproduct? The answer is NO. As stated above, the strategy is defined by firstselecting the equipment/cleaning procedure combinations to be challenged. Then,the product(s) can be selected based on a worst-case approach or just to testevery product – those will be the options.
5、Cleaning andSanitization are combined into one process
清潔和消毒合并為一個(gè)過(guò)程
Combiningcleaning and sanitation into one process is common mistake. Even though we cansay both cleaning and sanitization are combined in one step, the purpose ofboth steps are totally different.Some companies mistakenly believe that bycombining the steps combined but leaving the equipment idle for a prolongedperiod is sufficient. This is not an adequate approach. Cleaning isconcerned with removing the residues from the previous product (and thecleaning agent if applicable) using a worst-case dirty hold time. Sanitizationis concerned with the condition of the equipment before it is used next,particularly from a microbial consideration.
Once it has beendemonstrated that the cleaning is effective after the CV protocol executionusing a worst-case dirty hold time, the fact that you are keeping the equipmentidle for some time brings a set of totally different questions:
How does this combination of idle time and storage conditions affect the microbial bioburden on the equipment surface?
閑置時(shí)間和存放條件的這種組合如何影響設(shè)備表面的微生物負(fù)荷?
As a goodoption, many companies are establishing a sanitization process/step beforeusing the equipment again and this step is validated separately from thecleaning validation. Or, separately they may test for the microbial bioburdenin the equipment surface after the worst-case clean hold time has elapsed tosee whether a sanitization step is necessary. If test fails, the option will beto apply a sanitization step. Of course, these considerations will be affectedby the type of product/process being manufactured – from a topical drug, oralsolid dosage to the more critical sterile products, specifically thoseaseptically filled.
6、The Onlychemical residues of interest are the API residues
化學(xué)殘留只考慮API 殘留
In some cases,the residue of interest within a product formula or in the case of an APIproduction facility will be the API itself, but not always. Other components ofthe formula must also be considered, and those may be more difficult to clean,could represent a more toxic material or may just be present in higherconcentrations when compared to the API. In these cases, it is recommended totest both the API and the worst-case formula component based on those criteria.
在某些情況下,產(chǎn)品配方或 API 生產(chǎn)設(shè)施中需要考慮的殘留物將是 API 本身,但并非總是如此。配方的其他成分也需要考慮,這些成分可能更難清潔,可能代表毒性更高的材料，或者與API相比，可能只是以更高的濃度存在。在這些情況下,建議基于這些標(biāo)準(zhǔn)檢測(cè) API 和最壞條件的配方成分。
7、Applicationof LD50 directly into the Toxicity MACO calculation
LD50直接應(yīng)用于毒性MACO計(jì)算
The residuelimit calculation for toxicity is much more complex than most companiesrealize. It is not adequate to just take the LD50 value from a reference sourceor MSDS and insert that value into the formula with an arbitrarily selectedempirical factor. The fact that this formula includes at least one empiricalfactor requires a detailed consideration which may force some high-levelscientific analysis from a qualified expert such as a toxicologist. I suggestinvolving an expert if any of their formula components is considered to berelatively high-risk in terms of their toxicity.
8、Applicationof aprocess trainconcept when calculating surface areas andresidue limits for all drug processes
在計(jì)算所有藥物工藝的表面積和殘留限度時(shí)，應(yīng)用工藝鏈概念
Some industryexperts say that you “MUST” apply a process train concept for any CV effort.But that concept may not be applicable in every situation. Particularly whencalculating the total surface area for the entire process equipment train withconsideration for the total residues for the entire train. For example, theprocess train concept will make sense if the cleaning is actually conducted asa “process train” which is not the case in most operations. Because thecleaning of each equipment is different, it is recommended to validate thecleaning of each equipment separately.
9、Rinse samplesare enough to demonstrate cleaning process effectiveness
淋洗水足以證明清潔過(guò)程的有效性
The decision ofwhether rinse samples will be enough to demonstrate effectiveness of thecleaning procedure and that the residue levels have been reduced to acceptablelevels depends on several factors such as equipment design/physicalcharacteristics and formula components. Are there difficult locations where arinse sample will not have contact with the area and a swab sample must betaken? Are the selected formula components totally soluble under the rinseconditions and the solvent/water being used for the sample?
10、AnalyticalMethods must be specific for the particular entity being measured as residues
分析方法必須專屬于被檢測(cè)的殘留物
This questionhas been addressed extensively in the industry, and the consensus is – itdepends. If you can develop/find a non-specific method that canmeasure/quantify the residue of interest under the sampling conditions applied,you may be able to use this method. This decision will reduce the timenecessary for conducting your CV programby a considerablefactor. Another reason to consider using a non-specific method isjust the practicality for some operations where developing and validating aspecific method for each residue will imply extensive time/resources which theymay not have, and the value added by such efforts is not commensurate to theresources applied.
