Water, Water, Everywhere

Everyone probably feels like the above illustration sooner or later about their water system.

The Critical Role of Water in Pharmaceutical Manufacturing

In the pharmaceutical industry, we often joke that we’re primarily water companies that happen to make drugs on the side. This quip underscores a fundamental truth: water is a crucial component in drug manufacturing processes. Its purity and quality are paramount to ensuring the safety and efficacy of pharmaceutical products.

Why Water Quality Matters

Water is ubiquitous in pharmaceutical manufacturing, used in everything from cleaning equipment to serving as a key ingredient in many formulations. Given its importance, regulatory bodies like the FDA and EMA have established stringent Good Manufacturing Practice (GMP) guidelines for water systems in pharmaceutical facilities.

GMP Requirements for Water Systems

The GMPs mandate that water systems be meticulously designed, constructed, installed, commissioned, qualified, monitored, and maintained. The primary goal? Preventing microbiological contamination. This comprehensive approach encompasses several key areas:

System Design: Water systems must be engineered to minimize the risk of contamination.
Construction and Installation: Materials and methods used must meet high standards to ensure system integrity.
Commissioning and Qualification: Rigorous testing is required to verify that the system performs as intended.
Monitoring: Ongoing surveillance is necessary to detect any deviations from established parameters.
Maintenance: Regular upkeep is crucial to maintain system performance and prevent degradation.

Key Regulatory Requirements

Agency	Title	Year	URL
EMA	Guideline on the quality of water for pharmaceutical use	2020	https://www.ema.europa.eu/en/documents/scientific-guideline/guideline-quality-water-pharmaceutical-use_en.pdf
WHO	Good manufacturing practices: water for pharmaceutical use	2012	https://www.who.int/docs/default-source/medicines/norms-and-standards/guidelines/production/trs970-annex2-gmp-wate-pharmaceutical-use.pdf
US FDA	Guide to inspections of high purity water systems	2016	https://www.fda.gov/media/75927/download
PIC/S	Inspection of utilities	2014	https://picscheme.org/docview/1941
US FDA	Water for pharmaceutical use	2014	https://www.fda.gov/media/88905/download
USP	<1231> Water for pharmaceutical purposes	2020	Not publicly available
USP	<543> Water Conductivity	2020	Not publicly available
USP	<85> Bacterial Endotoxins Test	2020	Not publicly available
USP	<643> Total Organic Carbon	2020	Not publicly available
Ph. Eur.	Monograph 0168 (Water for injections)	2020	Not publicly available
Ph. Eur.	Monograph 0008 (Purified water)	2020	Not publicly available

Specific Measures for Contamination Prevention

To meet these GMP requirements, pharmaceutical manufacturers must implement several specific measures:

Minimizing Particulates

Particulate matter in water can compromise product quality and potentially harm patients. Filtration systems and regular cleaning protocols are essential to keep particulate levels in check.

Controlling Microbial Contamination

Microorganisms can proliferate rapidly in water systems if left unchecked. Strategies to prevent this include:

Regular sanitization procedures
Maintaining appropriate water temperatures
Implementing effective water treatment technologies (e.g., UV light, ozonation)

Preventing Endotoxin Formation

Endotoxins, produced by certain bacteria, can be particularly problematic in pharmaceutical water systems. Measures to prevent endotoxin formation include:

Minimizing areas where water can stagnate
Ensuring complete drainage of pipes
Regular system flushing

The Ongoing Challenge

Maintaining water quality in pharmaceutical manufacturing is not a one-time effort but an ongoing process. It requires constant vigilance, regular testing, and a commitment to continuous improvement. As regulations evolve and our understanding of potential contaminants grows, so too must our approaches to water system management.

Types of Water

These water types are defined and regulated by pharmacopeias such as the United States Pharmacopeia (USP), European Pharmacopoeia (Ph. Eur.), and other regional standards. Pharmaceutical manufacturers must adhere to the specific requirements outlined in these references to ensure water quality and safety in drug production.

Potable Water

Potable water, also known as drinking water, may be used for some pharmaceuticals bt is more commonly used in cosmetics. It can also be used for cleanings walls and floors in non-asceptic areas.

Key points:

Must comply with EPA standards or comparable regulations in the EU/Japan
Can be used to manufacture drug substances (bulk drugs)
Not suitable for preparing USP dosage forms or laboratory reagents

Purified Water (PW)

Purified water is widely used in pharmaceutical manufacturing for non-sterile preparations.

Specifications (USP <1231>):

Conductivity: ≤1.3 μS/cm at 25°C
Total organic carbon (TOC): ≤500 ppb
Microbial limits: ≤100 CFU/mL

Applications:

Non-parenteral preparations
Cleaning equipment for non-parenteral products
Preparation of some bulk chemicals

Water for Injection (WFI)

Water for Injection is used for parenteral drug products and has stricter quality standards.

Specifications (USP <1231>):

Conductivity: ≤1.3 μS/cm at 25°C
TOC: ≤500 ppb
Bacterial endotoxins: <0.25 EU/mL
Microbial limits: ≤10 CFU/100 mL

Production methods:

Distillation
Reverse osmosis (allowed by Ph. Eur. since 2017)

Sterile Water for Injection (SWFI)

SWFI is WFI that has been sterilized for direct administration.

Characteristics:

Sterile
Non-pyrogenic
Packaged in single-dose containers

Highly Purified Water (HPW)

Previously included in the European Pharmacopoeia, but now discontinued.

Type of Water	Description	USP Reference	EP Reference
Potable Water	Meets drinking water standards, used for early stages of manufacturing	Not applicable	Not applicable
Purified Water (PW)	Used for non-sterile preparations, cleaning equipment	USP <1231>	Ph. Eur. 0008
Water for Injection (WFI)	Used for parenteral products, higher purity than PW	USP <1231>	Ph. Eur. 0169
Sterile Water for Injection (SWFI)	WFI that has been sterilized for direct administration	USP <1231>	Ph. Eur. 0169
Bacteriostatic Water for Injection	Contains bacteriostatic agents, for multiple-dose use	USP <1231>	Ph. Eur. 0169
Sterile Water for Irrigation	Packaged in single-dose containers larger than 1L	USP <1231>	Ph. Eur. 1116
Sterile Water for Inhalation	For use in inhalators, less stringent endotoxin levels	USP <1231>	Ph. Eur. 1116
Water for Hemodialysis	Specially treated for use in hemodialysis, produced on-site	USP <1231>	Not specified

Additional relevant USP chapters:

USP <645>: Water for Pharmaceutical Purposes – Microbial Attributes
USP <85>: Bacterial Endotoxins Test

Always refer to the most current versions of the pharmacopoeial monographs and regulatory guidelines for detailed information.

Good Water System Design

Hygienic and Sanitary Design

The cornerstone of any good water system is its hygienic and sanitary design. This principle encompasses several aspects:

Smooth, cleanable surfaces: All surfaces in contact with water should be smooth, non-porous, and easily cleanable to prevent biofilm formation.
Self-draining components: Pipes and tanks should be designed to drain completely, eliminating standing water that could harbor microorganisms.
Accessibility: All parts of the system should be easily accessible for inspection, cleaning, and maintenance.

Material Selection

Choosing the right materials is crucial for maintaining water quality and system integrity:

Corrosion resistance: Use materials that resist corrosion, such as stainless steel (316L grade for high-purity applications) or appropriate food-grade plastics.
Smooth internal finish: Crevices are places where corrosion happens, electropolishing improves the resistance of stainless steel to corrosion.
Leachate prevention: Select materials that do not leach harmful substances into the water, even under prolonged contact or elevated temperatures.
Non-adsorptive surfaces: Avoid materials that may adsorb contaminants, which could later be released back into the water.

Microbial Control

Preventing microbial growth is essential for water system safety:

Elimination of dead legs: Design piping to avoid areas where water can stagnate and microorganisms can proliferate.
Temperature control: Maintain temperatures outside the optimal range for microbial growth (typically below 20°C or above 50°C).
Regular sanitization: Incorporate features that allow for effective and frequent sanitization of the entire system.

System Integrity

Ensuring the system remains sealed and leak-free is critical:

Proper sealing: Use appropriate gaskets and seals compatible with the system’s operating conditions.
Pressure testing: Implement regular pressure tests to identify and address potential leaks promptly.
Quality connections: Utilize sanitary fittings and connections designed for hygienic applications.

Cleaning and Sanitization Compatibility

The system must withstand regular cleaning and sanitization:

Chemical resistance: Choose materials and components that can tolerate cleaning and sanitizing agents without degradation.
Thermal stability: Ensure all parts can withstand thermal sanitization processes if applicable.
CIP/SIP design: Incorporate Clean-in-Place (CIP) or Steam-in-Place (SIP) features for efficient and thorough cleaning.

Capacity and Performance

Meeting output requirements while maintaining quality is crucial:

Proper sizing: Design the system to meet peak demand without compromising water quality or flow rates.
Redundancy: Consider incorporating redundant components for critical parts to ensure continuous operation.
Efficiency: Optimize the system layout to minimize pressure drops and energy consumption.

Monitoring and Control

Implement robust monitoring systems to ensure water quality:

Sampling points: Strategically place sampling ports throughout the system for regular quality checks.
Instrumentation: Install appropriate instruments to monitor critical parameters such as flow rate, pressure, temperature, and conductivity.
Control systems: Implement automated control systems to maintain consistent water quality and system performance.

Regulatory Compliance

Ensure the system design meets all relevant regulatory requirements:

Material compliance: Use only materials approved for contact with water in your specific application.
Documentation: Maintain detailed documentation of system design, materials, and operating procedures.
Validation: Conduct thorough system qualification to demonstrate consistent performance and quality.

By adhering to these principles, you can design a water system that not only meets your capacity requirements but also ensures the highest standards of safety and quality. Remember, good water system design is an ongoing process that requires regular review and updates to maintain its effectiveness over time.

The Challenge of Cleanroom Classification Harmonization

In the world of pharmaceutical manufacturing, cleanroom classifications play a crucial role in ensuring product quality and patient safety. However, a significant hurdle in the global harmonization of regulations has been a pain in our sides for a long time, that highlights the persistent differences between major regulatory bodies, including the FDA, EMA, and others, despite efforts to align through organizations like the World Health Organization (WHO) and the Pharmaceutical Inspection Co-operation Scheme (PIC/S).

The Current Landscape

United States Approach

In the United States, cleanroom classifications are primarily governed by two key documents:

The FDA’s “Sterile Drug Products Produced by Aseptic Processing” guidance
ISO 14644-1 standard for cleanroom classifications

The ISO 14644-1 standard is particularly noteworthy as it’s a general standard applicable across various industries utilizing cleanrooms, not just pharmaceuticals.

European Union Approach

The European Union takes a different stance, employing a grading system outlined in the EU GMP guide:

Grades A through D are used for normal cleanroom operation
ISO 14644 is still utilized, but primarily for validation purposes

World Health Organization Alignment

The World Health Organization (WHO) aligns with the European approach, adopting the same A to D grading system in its GMP guidelines.

The Implications of Disharmony

This lack of harmonization in cleanroom classifications presents several challenges:

Regulatory Complexity: Companies operating globally must navigate different classification systems, potentially leading to confusion and increased compliance costs.
Technology Transfer Issues: Transferring manufacturing processes between regions becomes more complicated when cleanroom requirements differ.
Inspection Inconsistencies: Differences in classification systems can lead to varying interpretations during inspections by different regulatory bodies.

The Missed Opportunity in Annex 1

The recent update to Annex 1, a key document in GMP regulations, could have been a prime opportunity to address this disharmony. However, despite involvement from WHO and PIC/S (and through them the FDA), the update failed to bring about the hoped-for alignment in cleanroom classifications.

Moving Forward

As the pharmaceutical industry continues to globalize, the need for harmonized regulations continues to be central. I would love to see future efforts towards harmonization here that would:

Prioritize alignment on fundamental technical specifications like cleanroom classifications
Consider the practical implications for manufacturers operating across multiple jurisdictions

While the journey towards full regulatory harmonization may be long and challenging, addressing key discrepancies like cleanroom classifications would represent a significant step forward for the global pharmaceutical industry.

FDA Nitrosamine Impurities Update

FDA guidance, “Control of Nitrosamine Impurities in Human Drugs,” revises the final guidance of the same name issued on February 24, 2021, by including information about nitrosamine drug substance related impurities (NDSRIs), recommending implementation of new nitrosamine control strategies, and providing an updated timeline for manufacturers and applicants to implement these recommendations.

Nitrosamine impurities are important to control because they are potential human carcinogens. Long-term exposure to these impurities at levels above acceptable limits can increase the risk of cancer. Nitrosamines can be found in various consumer products and the environment, and they have been detected in several pharmaceutical products since 2018, prompting recalls and regulatory actions. A lot of regulatory action. Nitrosamine impurities may be one of the biggest drivers of changes in the GMPs.

Current Regulatory View

Regulators, including the FDA, Health Canada, and the European Medicines Agency (EMA), have been actively working to address the presence of nitrosamine impurities in medications. The current regulatory view emphasizes:

Risk Assessment and Control: Regulatory agencies have established acceptable intake (AI) limits for nitrosamines in drug products. These limits are designed to minimize the risk of cancer associated with long-term exposure to these impurities.
Guidance and Frameworks: Agencies have issued guidance documents outlining frameworks for assessing and controlling nitrosamine impurities. For example, the FDA’s guidance includes recommendations for predicting the mutagenic and carcinogenic potential of nitrosamine drug substance-related impurities (NDSRIs) and provides AI limits based on carcinogenic potency categorization.
International Collaboration: There is significant collaboration among global regulators to harmonize approaches and methodologies for controlling nitrosamine impurities. This includes the adoption of the Carcinogenic Potency Categorization Approach (CPCA) to determine AI limits.
Industry Responsibility: Manufacturers are responsible for understanding their processes to prevent nitrosamine formation and for conducting risk assessments. They must implement control strategies and perform confirmatory testing to ensure that nitrosamine levels remain below the established AI limits.

Regulators are focused on ensuring the safety of pharmaceutical products by controlling nitrosamine impurities through comprehensive risk assessments, setting stringent AI limits, and fostering international cooperation. Companies need to make sure they are ahead of this matter.

Viral Controls in Facility Design

Facility design and control considerations for mitigating viral contamination risk is a holistic approach to facility design and controls, considering all potential routes of viral introduction and spread. A living risk management approach should be taken to identify vulnerabilities and implement appropriate mitigation measures.

Facility Considerations

Segregation of areas: Separate areas for cell banking, small-scale and large-scale upstream cell culture/fermentation, downstream processing, media/buffer preparation, materials management, corridors, and ancillary rooms (e.g. cold rooms, freezer rooms, storage areas).
Traffic flow: Control and minimize traffic flow of materials, personnel, equipment, and air within and between areas and corridors. Implement room segregation strategies.
Air handling systems: Design HVAC systems to maintain appropriate air quality and prevent cross-contamination between areas. Use HEPA filtration where needed.
Room Classifications
- For open operations:
  - Open sterile and aseptic operations must be performed in an environment where the probability of contamination is acceptably low, i.e. an environment meeting the bioburden requirements for a Grade A space.
  - Open bioburden-controlled processing may be performed in an ISO Grade 8/EU Grade C or EU Grade D environment as appropriate for the unit operation.
  - Open aseptic operations require a Grade A environment. Maintaining a Grade A cleanroom for large bioreactors is not feasible.
- For closed operations:
  - Closed systems do not require cleanroom environments. ICH Q7 states that closed or contained systems can be located outdoors if they provide adequate protection of the material.
  - When all equipment used to manufacture a product is closed, the surrounding environment becomes less critical. The cleanroom requirements should be based on a business risk assessment and could be categorized as unclassified.
  - Housing a closed aseptic process in a Grade C or Grade B cleanroom would not mitigate contamination risk compared to an unclassified environment.
  - For low bioburden closed operations, the manufacturing environment can be unclassified.

Equipment Considerations

Closed vs. open processing: Utilize closed processing operations where possible to prevent introduction/re-introduction of viruses. Implement additional controls for open processing steps.

Closure Level	Description
Closed Equipment	Single use, never been used, such as irradiated and autoclaved assembles; connections are made using sterile connectors or tube wielders/sealers
Functionally closed equipment: cleaned and sterilized	Open vessels or connections that undergo cleaning and sterilization prior to use and are then aseptically connected. The connection is then sterilized after being closed and remains closed during use.
Functionally closed equipment: cleaned and sanitized	Open vessels or connections that are CIPed including bioburden reducing flushes, but not sterilized before use and remain closed during use
Open	Connections open to the environment without subsequent cleaning, sanitization or sterilization prior to use

Operational Practices

Personnel controls: Implement rigorous training programs, safety policies and procedures for personnel working in critical areas.
Cleaning and sanitization: Establish frequent and thorough cleaning protocols for facilities, equipment, and processing areas using appropriate cleaning agents effective against viruses.
Material and equipment flow: Define procedures for disinfection and transfer of materials and equipment between areas to prevent contamination spread.
Storage practices: Implement proper storage procedures for product contact materials, intermediates, buffers, etc. Control access to cold rooms and freezers.

Additional Controls

Pest control: Implement comprehensive pest control strategies both inside and outside facilities, including regular treatments and monitoring.
Water systems: Design and maintain water systems to prevent microbial growth and contamination.
Process gases: Use appropriate filtration for process air and gases.
Environmental monitoring: Establish environmental monitoring programs to detect potential contamination early.

FDA Speaks About Recent CRLs for Manufacturing

I hasn’t been difficult to notice that a whole lot of biological new drug applications have been rejected in the last few years, many for CMC reasons. Recently CDER Director Patrizia Cavazzoni spoke on the matter at a recent at a Duke University and FDA event at the National Press Club iin the video above.

“Our standards have not changed. We have exactly the same standards as we had in 2018 and 2019,” she said, before going on to talk about how the quality related issues the FDA is seeing: contamination, overall oversight, manufacturing controls or insufficient quality management systems.

Max Van Tassell, a senior pharmaceutical quality assessor in CDER’s Office of Pharmaceutical Quality, provided insights from analyzing 100 complete response letters (CRLs) for Biologics License Applications (BLAs) issued between 2014 and 2024. He noted that facility-related deficiencies in CRLs typically stem from inadequate demonstration that proposed corrective and preventive actions would effectively mitigate risks identified during on-site inspections.

It should be a key takeaway from this presentation that:

We aren’t doing enough risk management in the right ways.
We treat our facility as a secondary consideration, especially in biosimilars.
Companies do a really bad job building trust with health authorities.