Aseptic Transfer Risk Assessment: A Case Study

Aseptic Transfer Risk Assessment: A Case Study | IVT By Tim Sandle, Ph.D. May 6, 2015 11:00 pm PDT

Peer Reviewed: Case Study ABSTRACT This paper uses one example of a risk assessment approach to illustrate how risk assessment can be incorporated into good manufacturing controls. The specific activity assessed involves transferring a set of sterilised stoppers from an autoclave to a filling machine within a sterile manufacturing facility. The risk assessment approach adopted is a form of HACCP (Hazard Analysis Critical Control Points). Approaches to risk assessments are discussed. Key activities are described. Documentation is critical. There is no such thing as “zero risk.” A decision is thus required as to what is “acceptable risk. Key components of HACCP including hazard analysis and critical control points. The “seven pillars” of HACCP are described. Stepwise activities needed to accomplish the risk assessment are discussed. This case study described a low risk activity. Rationale for the assessment is described. This discussion described a risk assessment approach using a relatively simple case to illustrate its potential for other applications.

INTRODUCTION Risk analysis and risk management are significant considerations in current pharmaceutical manufacturing practices. All areas and functions in the pharmaceutical manufacturing plant assess level of risk to a process and then take steps to eliminate that risk. This paper uses one example of a risk assessment approach to illustrate how risk assessment can be incorporated into good manufacturing controls. Risk assessment involves identifying risk scenarios either prospectively or retrospectively. The former involves determining what can go wrong in the system and all the associated consequences and likelihoods; the latter this looks at what has gone wrong. Risk assessment is then used to assess the process, product, or environmental risk and to aid in formulating the appropriate actions to prevent the incident from re-occurring (1). The case examined here is a prospective risk assessment.

The case study involves transferring a set of sterilised stoppers from an autoclave to a filling machine within a sterile manufacturing facility. The risk assessment approach adopted is a form of HACCP (Hazard Analysis Critical Control Points).

APPROACHES TO RISK ASSESSMENT There are various approaches to risk assessment being used in the pharmaceutical industry. Each has their respective merits. The use of risk assessment is commonly expected by regulatory authorities (2). There are various tools that can be drawn upon for conducting risk assessments. Some common methods include FMEA (Failure Mode and Effects Analysis), FTA (Fault Tree Analysis), and HACCP (Hazard Analysis Critical Control Points). Many of these employ a scoring approach. No definitive method exists for all applications and different approaches are useful for different situations (3). The various approaches differ in their structure and with the degree of complexity involved. Nonetheless, there are some broad similarities. The different analytical tools are similar in that they generally involve:      

Constructing diagrams of work flows, Pin-pointing areas of greatest risk, Examining potential sources of contamination, Deciding on the most appropriate sample methods, Helping to establish alert and action levels, Taking into account changes to the work process / seasonal activities.

Documenting risk assessments is important. When a risk assessment is presented to an auditor, it is likely that the reviewer will be concerned with whether the risk assessment is traceable to a risk methodology and that the process is clear, understandable, and that it has been performed consistently. In this sense, the reviewer will want to understand how the decisions were made and that the risk (or problem) was defined upfront. With the question established, the reviewer will also wish to see if the process performed actually answered the question in a meaningful way using scientific principles. Important points to remember for any risk assessment are the following:  

There is no such thing as “zero risk.” A decision is thus required as to what is “acceptable risk.” Risk Assessment is not an exact science - different people will have different perspectives on the same hazard.

Risk assessments should always:  

Be based on systematic identifications of possible risk factors Take full account of current scientific knowledge

      

Be conducted by people with experience in the risk assessment process and the process being risk assessed Use factual evidence supported by expert assessment to reach conclusions Do not include any unjustified assumptions Identify all reasonably expected risks-simply and clearly, along with a factual assessment and mitigation where required Be documented to an appropriate level and controlled/approved Ultimately be linked to the protection of the patient Should contain objective risk mitigation plan.

Before embarking upon risk assessment it is important to establish and to define: 



Develop and agree on the risk question. A clearly defining the risk question facilitates selection of the appropriate risk assessment tool, identifies relevant data, information and assumptions; assists in the identification of resources, responsibilities and accountabilities; and ensures that appropriate focus on the business objective is maintained. Select the most appropriate risk assessment tool. The selected risk assessment method or tool will be used to organise collected data, understand what steps can be taken to reduce or control risk, and to help make appropriate decisions.

APPLICATIONS TO CLEANROOM ENVIRONMENTS AND PHARMACEUTICAL PROCESSES The primary risk assessment approaches can allow for a complete review of operations within the cleanroom ensuring those facilities, operations and practices are also satisfactory. The approaches recognise a risk, rate the level of the risk, and then develop a plan to minimise, control, and monitor the risk. For example, the monitoring of the risk will help to determine the frequency, locations, and level for environmental monitoring (4). This case study outlined in this paper uses a modification of the HACCP method, which is sometimes called the “Lifecycle Approach”. The approach adopted has been used for similar assessments of pharmaceutical processes (5). There are numerous risk factors to be considered when analysing aseptic processing. The HACCP approach can help to identify these risk factors. The following factors shown in Figure 1 are useful to note when undertaking HACCP analysis in pharmaceutical manufacturing.

FIGURE 1: ASEPTIC PROCESSING RISKS

HACCP HACCP was developed during the 1960’s from collaboration between NASA, a food company (the Pillsbury Company), and the US Army Natick Laboratories. The objective was to provide a zero-defect food supply for astronauts. HACCP was derived from Failure Mode Analysis (6). There are two key components of HACCP:  

Hazard Analysis: Determining what microbiological, physical, or chemical risks are associated with a process. Critical Control Point: A point, step, or procedure at which control can be applied.

HACCP generally involves an assessment of the following conditions – known as the “seven pillars.” 1. Conducting a hazard analysis. List all potential hazards associated with each step, conduct a hazard analysis, and consider any measures to control identified hazards. 2. Determining the Critical Control Points (CCPs). Critical control points have to be defined as processing steps at which necessary action can be applied to ensure and maintain compliance with specified conditions. Those points are identified with appropriate measures that can be applied to control each hazard. If no such critical control points can be established, product specific validation should eliminate potential risks of a certain process step. 3. Establishing critical limit(s). Establish critical limits for each CCP. 4. Establishing a system to monitor control of the CCP. 5. Establishing the corrective action to be taken when monitoring indicates that a particular CCP is not under control. 6. Establishing procedures for verification to confirm that the HACCP system is working effectively. 7. Establishing documentation and record keeping. Aspects of these have been utilized in the case study. In general, the advantages of the HACCP approach are that it allows for a systematic overview of the process for the evaluation of each processing step, allows each step to be examined the possible risks, and allows for the specification of measures required for controlling each risk. The primary disadvantage of HACCP is that, unlike FMEA, HACCP cannot be used to rank or prioritize risks.

CASE STUDY This case study describes a specific activity within the sterile area of a pharmaceutical manufacturing facility. An autoclave that is connected to the filling room is unavailable due to a long-term malfunction. The autoclave is used to prepare the stopper for a sterile injectable product and the need to process an important batch has arisen. The production management at the facility has decided that stoppers will be sterilised using a different autoclave within the facility and that the sterilised stoppers will be transported to the filling machine. The stopper swill be loaded by trained operators into a sterilised hopper drum and wheeled through part of the facility. Putting aside any doubts to the suitability of this process, the quality personnel have been asked to risk assess the proposed procedure.

DECONSTRUCTING THE PROCESS Four stepwise activities are needed to accomplish the risk assessment: 

A route map. The facility is drawn and the route indicated

  

Identification of hazards, which can be divided into biological; physical; equipment; transport and chemical. This will allow an assessment of existing control measures Process flow Assessment of environmental monitoring. This will determine if the activity is safe to proceed (7).

Route Map The first step was to outline a route map. This focused on transporting the stoppers by the shortest and safest route possible as illustrated in figure 2.

FIGURE 2: ROUTE MAP. Arrows indicate stopper transfer route from autoclaves to filling room

Identification of Hazards The second step was to understand the hazards and the process. The primary hazards with an aseptic process are biological, physical, and equipment related (8) as displayed in Table 1.

TABLE 1a: IDENTIFICATION OF HAZARDS

TABLE 1b: IDENTIFICATION OF HAZARDS

Process flow The third step was to outline the process flow as shown in Figure 3.

Figure 3a: Process flow with CCPs (critical control points) marked. Process flow identifies hazards.

Figure 3b: Process flow with CCPs (critical control points) marked. Process flow identifies hazards.

Environmental monitoring The fourth step involved assessing dynamic state viable microbiological environmental monitoring and particle counts. If data have been satisfactory and there are no indications of adverse trends, the proposal can be advanced. If there is a level of risk, this must be addressed first using appropriate corrective and preventative action. Undertaking an unusual event in a high-risk situation will compound the problem.

RISK ASSESSMENT – PERFORM A SIMULATION

Before undertaking the activity, a simulation should be performed so that any previously unforeseen problems can be noted and further preventative measures taken. If any variability is expected, the simulation should be repeated. The simulation should be timed and the number of staff required noted. The focus should remain on the ease of transit. In this case study, the duration of the activity is five minutes and the number of staff involved is two.

CONCLUSION From three possible options -- high risk, medium risk or low risk -- the conclusion of this risk analysis was that the risk level was low. This evaluation is based on the successful identification of the hazards and control points. The strongest evidence for this came from the following:      

The process being performed by trained clean room personnel operating in an aseptic manner The autoclaved stoppers being contained within a sealed box. The seal remains intact throughout the transfer The outlet at the bottom of the box has an integrity tested vent filter An additional vent filter is placed on the top of the box The stoppers are wheeled on a trolley which minimises human intervention The microbiological environmental monitoring for the rooms is satisfactory.

It is important to note the impact of change and to review any risk assessments on a regular basis in developing any risk assessment. This case study may or may not be typical. It may or may not be wise for an organisation to undertake such an activity. The purpose of this discussion was to demonstrate an example of the risk assessment approach using a relatively simple case so that the wider application can be appreciated.

REFERENCES 1. Sandle, T. (2011): Risk Management in Pharmaceutical Microbiology. In Saghee, M.R., Sandle, T. and Tidswell, E.C. (Eds.) Microbiology and Sterility Assurance in Pharmaceuticals and Medical Devices, New Delhi: Business Horizons, pp553-588 2. Sandle, T. and Lamba, S. S. Effectively Incorporating Quality Risk Management into Quality Systems. In Saghee, M.R. (2012) Achieving Quality and Compliance Excellence in Pharmaceuticals: A Master Class GMP Guide, New Delhi: Business Horizons, pp89-128 3. Sandle, T. (2013). Contamination Control Risk Assessment. In Masden, R.E. and Moldenhauer, J. (Eds.) Contamination Control in Healthcare Product Manufacturing, Volume 1, DHI Publishing, River Grove: USA, pp423-474

4. Sandle, T. (2003): The use of a risk assessment in the pharmaceutical industry – the application of FMEA to a sterility testing isolator: a case study, European Journal of Parenteral and Pharmaceutical Sciences, 8(2): 43-49 5. Munro, M. J., Millar, B. W. and Radley. A. S. (2003): A Risk Assessment of the Preparation of Parenteral Medicines in Clinical Areas, Hospital Pharmacist, Vol. 10, pp303-305 6. Gavin, A., and Weddig, L.M. (Eds.). (1995): Canned Foods: Principles of Thermal Process Control, Acidification and Container Closure Evaluation, Food Processors Institute, Washington, D.C., pp5-10 7. Sandle, T. (2006) Environmental Monitoring Risk Assessment, Journal of GXP Compliance, 10(2): 54-73 8. Whyte, W. and Eaton, T. (2004): Assessing microbial risk to patients from aseptically manufactured pharmaceuticals, European Journal of Parenteral and Pharmaceutical Sciences, 9 (3): 71-79 9. Whyte, W. and Eaton, T. (2004): Microbiological contamination models for use in risk assessment during pharmaceutical production, European Journal of Parenteral and Pharmaceutical Sciences, 9 (1): 11-15 10. Sandle, T. (2004): General Considerations for the Risk Assessment of Isolators used for Aseptic Processes, Pharmaceutical Manufacturing and Packaging Sourcer, Samedan Ltd, Winter 2004, pp43-47