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West RTS

West RTS

West RTS components are delivered in packaging appropriate for direct sterilization. West RTS packaging components were developed to provide a high-performance solution for biopharmaceutical manufacturers who are looking to reduce costs related to capital expenditures. West RTS stoppers are delivered in bags that can be introduced directly into sterilizers.

Component Testing

West RTS components have been tested to meet specified bioburden, bacterial endotoxin, particulate and, if applicable, silicone oil levels.

  • Bioburden:
    • Testing for bioburden is essential in assessing whether the sterilization process is adequate. An unvalidated level of bioburden on stoppers raises questions about the assurance level of the validation of the stopper sterilization process.
  • Endotoxin:
    • Maintaining microbiologically clean components after they have been washed is critical for preventing contamination during storage, shipping and handling.
  • Particulate matter:
    • Particulate matter on stoppers can be transferred to packaged drug products, resulting in particles in the drug that can lead to end-of-the-line rejects and could cause major problems for complex protein and peptide drugs.

Process and Specifications

West RTS products are handled in a class 100,000 cleanroom (ISO 8) where they are also siliconised. After washing, the components are unloaded and packed in a class 100 cleanroom (ISO 5).

West RTS components meet the following product specifications:

  • Bacterial endotoxin levels of NMT 0.125 Endotoxin Units (EU) per cm2 of stopper surface area
  • Bioburden level of NMT 5 Colony Forming Units (CFU) per 100 cm2 of stopper surface area
  • Particle level, specification in agreement with customer
  • Silicone oil level not tested

These specification limits are monitored only, but can be measured per batch on customer demand at an additional cost.

West RTS Packaging

The standard packaging for West RTS stoppers is a sterilisable bag in combination with an outer clipped polyethylene bag. Customers may request an isolator bag or other packaging combinations to fit their requirements.