The Role of CCIT in Ensuring Sterility for Injectable Drug Products

Container Closure Integrity Testing (CCIT) plays a critical role in pharmaceutical quality assurance, particularly for injectable drugs - it's a fundamental component of patient safety and public health. Even the smallest breach in container closure integrity can compromise sterility, potentially leading to contamination, patient harm, or costly product recalls.

 

So how can CCIT safeguard sterility and examine common injectable packaging types? And which testing methods are best suited to identify micro-leaks that pose a risk to product safety?

Why Sterility Is Critical for Injectables

Injectable drug products, also known as parenterals, bypass the body’s natural defense systems such as the digestive tract and skin barrier. As a result, they are highly susceptible to microbial contamination, which can lead to severe health consequences - from localized infections to systemic conditions such as sepsis.

Real-world case examples include:

• 2007 U.S. outbreak of Exophiala fungus infections linked to contaminated injectable pain medication due to faulty vial seals.
• 2012 New England Compounding Center incident, where poor sterility controls led to a fungal meningitis outbreak, causing over 60 deaths.

Such cases underscore the non-negotiable need for validated and highly sensitive CCIT methods in parenteral product manufacturing.

What are common container types for injectables?

Injectable drug products are typically packaged in:

• Glass vials (lyophilized or liquid)
• Pre-filled syringes (PFS)
• Autoinjectors
• Cartridges (used in autoinjectors or pen systems)
• Ampoules
• IV-Bags
• BFS Bottles

 

Each format presents unique sterility challenges:

• Vials rely on the crimped cap and rubber stopper system to maintain integrity.
• Pre-filled syringes must prevent ingress through the plunger and needle shield.
• Cartridges require precision sealing around end caps and plungers.
• BFS bottles have a critical point between the closure and the seal.

 

Understanding these configurations is essential when selecting a CCIT method.

Best CCIT Methods for Detecting Micro-Leaks

Regulatory guidance such as USP <1207> and EU GMP Annex 1 emphasizes the use of deterministic, quantitative testing methods over traditional probabilistic techniques like dye ingress or microbial challenge. Deterministic methods provide objective, repeatable, and scientifically measurable results, ensuring a higher level of reliability and sensitivity in leak detection. These methods allow for precise quantification of leak sizes and provide digital data that can be used for real-time monitoring, trending, and compliance reporting. In contrast, probabilistic methods depend on visual interpretation or microbial growth, which can introduce subjectivity, have lower sensitivity, and may miss micro-leaks that pose serious sterility risks. For injectable products, where even minute contamination can have significant clinical consequences, deterministic methods are essential to meeting the stringent sterility assurance standards required by regulators.

1. LFC method® (Advanced Vacuum Decay method)

Working principle:

• Differential pressure inside the test chamber indicates a leak
• Detects smallest leaks even if they are covered with liquid
• Non-destructive
• Suitable for lab environments and 100% in-line testing
• Optimized to test for leaks in both headspace as well as liquid filled part of the container
• High test sensitivity of down to 1.0e–03 mbar *l/s
• Provides deterministic, quantitative data

Container Types:

• Works well with many container types, like vials, cartridges, ampoules, IV-Bags, pre-fill syringes, BFS Bottles and autoinjectors

Drug products:

• Suitable for liquids, that can vaporize and lyo products as well as products containing alcohols

Compliant with:

• Fully compliant with USP <1207>
• Fulfils EU GMP Annex 1 requirements

2. Vacuum Decay Testing

Working principle:

• Differential pressure inside the test chamber indicates a leak
• Non-destructive
• Suitable for lab environments and 100% in-line testing
• Provides deterministic, quantitative data

Container Types:

• Ideal for rigid containers like glass vials and medical devices 

Drug products

• Suitable for dry content like powder or lyophilizates

Compliant with:

• Fully compliant with USP<1207>
• Fulfills EU GMP Annex 1 requirements
• ASTM F 2338

3. Pressure Decay Testing

Working principle:

• Reduction of the pressure level inside the test chamber will indicate the presence of a leak due to gas transfer into the container
• Does not rely on altering the internal headspace of the container
• Evaluates the integrity of the complete container-closure system
• Non-destructive
• Suitable for lab environments and 100% in-line testing
• Provides deterministic, quantitative data

Container types:

• Ideal for glass ampoules and vials

Drug products:

• Suitable for liquids that don’t allow vaporization such as oily and toxic products

Compliant with:

• Fully compliant with USP<1207> guidelines
• Fulfills EU GMP Annex 1 requirements

4. Force Decay Technology

Working principle:

• Measures force changes caused by potential leaks
• Allows the inspection of critical welding areas (port)
• Non-destructive
• Ideal for lab and inline testing in high-throughput environments
• Provides deterministic, quantitative data

Container types:

• Suitable for flexible packaging like IV Bags in different format sizes

Drug products:

• Liquid products

Compliant with:

• Fully compliant with USP<1207> guidelines
• Fulfills EU GMP Annex 1 requirements

5. Headspace Analysis (HSA)

Working principle:

• Leak is measured by gas ingress over time
• Permanent and temporary leaks are detected
• Can measure up to two gases (O₂, CO₂ or H₂O) simultaneously
• Applicable for CCIT, Media-Fill inspection or vacuum level verification
• Non-destructive
• Suitable for lab environments and 100% in-line testing
• Smallest leakages of the Kirsch criteria can be reached by combining with the CO₂ bombing method

Container types:

• Suitable for glass vials, ampoules, pre-filled syringes, autoinjectors, BFS bottles

Drug Products:

• Appropriate for oxygen-sensitive formulations
• Applicable for liquid, lyophilized and solid products

Compliant with:

• Fully compliant with USP<1207> guidelines
• Fulfills EU GMP Annex 1 requirements

When to use which CCIT method?

Container Type	Recommended Method	Notes
Glass Vials, Ampoules	LFC method®, Vacuum Decay, Pressure Decay,  HSA	Vacuum Decay excels for rigid containers; HSA useful for oxygen-sensitive products. The first inline CCIT method using HSA in combination with bombing has been developed for ampoules.
Pre-filled Syringes	LFC method®, HSA	To ensure sterility, it is essential that the stopper is not moveable by the vacuum generated.
Cartridges	LFC method®	Vacuum Decay for rigid formats provides fast inline testing for small volumes. To ensure sterility, it must be ensured that the stopper is not moveable by the vacuum generated
Autoinjectors	LFC method ®, HSA	HSA only possible if there is a visible headspace
IV Bags / Pouches	Force Decay, LFC method®	Flexible, often large-volume containers require gentle yet precise methods.
BFS Bottles	LFC method ®, HSA	HSA ideal to inspect the sterility between the stopper and the cover foil.

Advantages of Differential Pressure-Based Methods for Injectable Applications

Differential pressure-based leak detection technologies, such as vacuum decay and force sensor methods, offer a robust and deterministic approach for ensuring container closure integrity in injectable drug products. These methods operate by detecting minute changes in pressure across a sealed chamber or sensor interface, which can indicate the presence of a leak.

Key advantages include:

• Non-destructive testing that enables 100% inspection without damaging the product
• High sensitivity to micro-leaks, especially in rigid container formats
• Versatility for a range of packaging formats, including vials, syringes, cartridges, IV bags and BFS bottles
• Deterministic and quantitative results in compliance with USP <1207> and EU GMP Annex 1
• No need for tracer gases or modified headspace, preserving product and packaging integrity
• Digital data output supporting audit trails, real-time monitoring, and regulatory submissions in compliance with 21 CFR part 11

WILCO’s approach in regards to Leak Detection

At WILCO AG, we are committed to delivering advanced, non-destructive leak detection solutions that ensure the highest standards of container closure integrity (CCI) across a diverse range of pharmaceutical packaging formats. Our approach is centred on providing deterministic and quantitative testing methods that align with regulatory requirements and industry best practices. With the invention of the LFC method®, WILCO has set a new industry benchmark in leak testing.

Commitment to Innovation and Quality 

With over 50 years of experience, WILCO continues to pioneer advancements in leak detection technologies, ensuring that our clients benefit from state-of-the-art solutions that enhance product safety and compliance. We would be happy to evaluate the most suitable test method for your products.