Flexible vs. rigid isolators

Why containment is more important than ever

The pharmaceutical and biopharmaceutical industries are increasingly developing highly potent compounds such as HPAPIs (Highly Potent Active Pharmaceutical Ingredients) and ADCs (Antibody-Drug Conjugates). At the same time, requirements for operator protection and the prevention of cross-contamination continue to increase.

Especially for products with exposure limits in the OEB 5 and OEB 6 range, closed containment systems have become a key technology. Isolators provide a reliable barrier between the product, the process and the operator. However, not all isolators are the same.

What is a flexible isolator?

Flexible isolators consist of a combination of robust film materials, glove ports and a controlled airflow system.They create a closed working environment without the need for a rigid enclosure.

Typical features:

• Lightweight and modular design
• Fast installation and commissioning
• Adaptable to different processes
• Small footprint
• Often available as a single-use solution

Flexible isolators are frequently used where processes change regularly or a high degree of flexibility is required.

What is a rigid isolator?

Rigid isolators are typically manufactured from stainless steel and equipped with glass viewing panels. They are integrated containment systems that form a permanently installed, fully enclosed processing environment.

Typical features:

• Robust and durable construction
• Maximum process stability
• Excellent cleanability
• Designed for long-term, high-volume production
• High degree of automation possible

They are primarily used in production environments where processes are standardized and remain unchanged over long periods.

Flexible vs. rigid isolators: a practical comparison

Criterion	Flexible Isolator	Rigid Isolator	Advantage
Flexibility	Quick adaptation to new products or processes Ideal for multi-product facilities Easy to expand or reconfigure	Less flexible after installation Optimized for dedicated production processes	Flexible isolators
Cleaning & Validation	Reduced cleaning effort depending on the design Single-use components can simplify validation	Well-established cleaning and decontamination procedures Particularly suitable for repetitive GMP processes	Depends on the process and validation strategy
Investment Costs	Lower initial investment Shorter implementation times Lower infrastructure costs	Higher initial investment Cost-effective over the long term at high utilization	Flexible isolators
Scalability	Ideal for development and pilot phases Easily adapted to changing requirements	Excellent for continuous high-volume manufacturing High process reliability for large production volumes	Depends on the production model
Containment Level	High, up to OEB 5–6	Very high, up to OEB 6	Both technologies can meet the highest containment requirements.
Typical Applications	HPAPI development ADC research and early production phases Clinical batches Small to medium batch sizes Frequent product changeovers Pilot and scale-up projects	Manufacturing of highly potent compounds (HPAPIs) Aseptic processing Commercial manufacturing High production volumes Standardized processes Long-term production concepts Automated production lines Continuous manufacturing	The best solution is the one that fits your process.

Conclusion

The best solution is the one that fits your process. The question is not whether flexible or rigid isolators are generally better. What matters is which solution best meets your process requirements today and in the future.

If flexibility, rapid implementation and frequent product changes are your priorities, flexible isolators often offer clear advantages. For long-term production with high volumes and maximum process stability, rigid isolators may be the better choice.

Your decision guide

Ask yourself the following questions:

✓ How often do products or processes change?
✓ What batch sizes are being produced?
✓ Which OEB requirements must be met?
✓ How important are scalability and future expansion?
✓ Which investment and operating cost model best fits your strategy?

Not sure which containment solution is best for your application? Contact the experts at Lugaia for a no-obligation consultation. Together, we will analyze your requirements and develop the optimal containment strategy for your HPAPI, ADC or OEB 5/6 application.