Westar® RS

West Westar® RS components are delivered in packaging appropriate for direct sterilization. Westar RS packaging components were developed to provide a high-performance solution for biopharmaceutical manufacturers who are looking to reduce costs related to capital expenditures and validation studies. The Westar RS process ensures consistent component preparation and minimized variability in your sterile operations. Choosing the Westar RS process allows pharmaceutical companies to streamline operations by reducing steps in component preparation. Westar RS stoppers are delivered in bags that can be introduced directly into sterilizers.

Component Testing

Westar RS components have been tested and are certified 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 are 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.

During the development of the Westar process, West performed Statistical Process Control (SPC) studies to identify the family of variation (load to load, within load, day-to-day, etc.) and designed the process to reduce the variability of the silicone level on processed stoppers.

Westar RS Process and Specifications

The process validation data demonstrate that the Westar RS process is capable of reducing the endotoxin content by at least 3 logs. Before the washing process, all Westar products are handled in a class 100,000 cleanroom (ISO 8) where they are also loaded into the washer. After washing, the components are unloaded and packed in a class 100 cleanroom (ISO 5).

Westar RS components meet the following product specifications:

  • Bacterial endotoxin levels of NMT 0.1 Endotoxin Units (EU)/mL (per 10 pooled samples) equals NMT 1 EU per stopper
  • Bioburden level of NMT 5 Colony Forming Units (CFU) per 100 cm2 of stopper surface area
  • Particulate matter content NMT 2.5 PCI (Proved Clean Index)
  • Specified silicone oil level when applicable
  • Specification established after 30 wash loads
  • Validated siliconization process

The named specification limits are tested per delivery batch and reported in the certificate of analysis (CoA)

West has site-specific Drug Master Files with the FDA for the Westar process performed at its plants in Le Nouvion (France), Eschweiler (Germany), Jurong (Singapore) and Jersey Shore (U.S.)

Westar RS Packaging

The standard packaging for Westar 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.

Westar® is a registered trademark of West Pharmaceutical Services, Inc., in the United States and other jurisdictions.