Sterile powder manufacturing presents one of the most demanding combinations of aseptic processing and high-containment production.
Reusable containers, machine parts and thermosensitive materials must each follow dedicated preparation pathways before entering the filling environment, while uninterrupted production campaigns require a sufficient number of sterile containers to be available before filling can even begin.
The challenge therefore extends well beyond aseptic filling itself: manufacturers must coordinate washing, depyrogenation, sterilization, material bio-decontamination, protected transfers and containment into a single validated manufacturing workflow that preserves both product sterility and operator safety.
Sterility is not established by a single technology but preserved through every transition between preparation, transfer, filling and packaging. We design each interface between washing, depyrogenation, sterilization, bio-decontamination, automated handling and barrier systems as part of one controlled manufacturing workflow, transforming multiple independent operations into a repeatable sterile production campaign.
Independent pressure and temperature control applies counterpressure through heating and cooling, protecting 5–7 N seals while delivering effective terminal sterilization
Magazines leave the sterilizer and transfer directly toward secondary packaging, sustaining line continuity and eliminating manual product handling after treatment.
Robotic handling moves magazines from primary packaging to the sterilizer without product extraction or operator contact, maintaining throughput and a touchless production flow
Preparing the production line for the next campaign.
Validated washing removes process residues and establishes the required cleanliness state for reusable product-contact, machine and format parts. Cycle parameters, load configuration and mechanical action are developed around the materials and geometries involved, preparing every surface for the selected downstream treatment and preventing cleaning from becoming an uncontrolled variable within the aseptic-transfer route.
Restoring sterility before production begins.
Compatible reusable parts are packaged in bags or loaded into closed canisters before steam sterilization. The process is developed around the complete load configuration to govern air removal, steam penetration, condensate management and drying. Once treated, the selected packaging or transfer system preserves the sterile state during unloading, movement and introduction into the aseptic processing environment.
Introducing sensitive materials without thermal stress.
Not every production material can tolerate steam sterilization or dry heat. Thermosensitive accessories, environmental monitoring tools and auxiliary production materials are transferred into the classified manufacturing area through validated hydrogen peroxide bio-decontamination. This approach enables safe material introduction while preserving aseptic conditions and avoiding thermal damage to sensitive components.
Establishing the required cleanliness state.
Before sterile processing can begin, reusable aluminium kegs are washed to remove manufacturing residues and prepare every product-contact surface for downstream depyrogenation. Washing represents the first operation of the production campaign, creating consistent starting conditions for sterile container preparation while supporting repeatable processing of every batch of reusable primary containers.
Washing and steam sterilization are integrated within one system to establish cleanliness and sterility through a coordinated process. This architecture reduces equipment interfaces, material movements and classified-space requirements while strengthening control between the two treatments. It is selected for compatible reusable loads when layout efficiency, operator protection or a more contained process route drives the transfer strategy.
Preparing sterile and pyrogen-free primary containers.
After washing, aluminium kegs undergo validated dry-heat depyrogenation before entering the protected aseptic workflow. The process combines sterilization with endotoxin reduction, preparing reusable primary containers for direct contact with sterile powder products. By establishing both sterility and pyrogen control upstream of filling, depyrogenation extends contamination control beyond microbial reduction alone.
The rapid growth of biologics, nanoparticle-based medicines and Advanced Therapy Medicinal Products (ATMPs) is redefining the relationship between pharmaceutical formulations and primary packaging.
Interactions between proteins such as insulin, nanoparticles and container surfaces are well-recognised phenomena that can influence product stability, efficacy and patient safety. As these therapies become increasingly sensitive, material compatibility can no longer be considered an intrinsic property of the container alone.
When manufacturers seek to move away from EtO towards a method that reduces toxic-residue concerns and the potential burden on patients, workers and the environment, selecting an alternative sterilant is only the beginning.
This is particularly true for the low-temperature sterilization of RTU glass vials in their complete packaging configuration. The sterilant must pass through the outer transport box, multiple porous barriers and enclosed packaging interfaces before reaching the internal vial surfaces. The same structure must then release residual sterilant within an acceptable aeration time.
30 Kegs/washing batch
maximum number of aluminium kegs prepared during a single washing cycle before downstream depyrogenation
60
sterile Kegs buffer accumulated inside the RABS before the filling campaign begins, ensuring uninterrupted production
OEB 5
contained filling performed under high-containment conditions to protect operators during sterile powder processing
≈1 h
customized washing cycle
They have different process objectives. Machine parts require washing followed by terminal steam sterilization before line assembly, while aluminium kegs undergo washing followed by dry-heat depyrogenation before entering the aseptic production flow.
Continuous powder filling cannot be interrupted. A sufficient number of washed and depyrogenated kegs must therefore be accumulated inside the Grade A RABS before production begins, ensuring a continuous supply of sterile containers throughout the manufacturing campaign.
Dry-heat depyrogenation prepares reusable primary containers by combining sterilization with endotoxin reduction before direct contact with sterile powder products.
Materials that cannot withstand thermal treatment are transferred through validated hydrogen peroxide pass boxes before entering the classified production environment..
Because product sterility and operator protection depend on every transition between cleaning, sterilization, depyrogenation, material transfer and filling—not on any single technology alone.
The Grade A RABS acts as a sterile parking area where depyrogenated kegs are accumulated before controlled transfer into the filling isolator, supporting uninterrupted production campaigns.
Knowledge Hub Regulatory
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