Which requirements apply to GMP-compliant design and validatable cleaning in pharmaceutical production?
GMP-compliant design comprises the hygienic layout of plants, equipment and process paths so that medicinal products can be manufactured and cleaned reproducibly in the required quality across the entire life cycle. The focus is on avoiding contamination, cross-contamination and microbial niches as well as on complete, demonstrably effective cleanability.
Hygienic design
Surface quality
Product-contact surfaces typically consist of austenitic stainless steel, for example 1.4404 or 1.4435. Smooth surfaces and low roughness facilitate cleaning and reduce build-up as well as the formation of biofilms.
Freedom from dead space
Dead spaces should be avoided as far as possible so that process media and cleaning liquids can circulate sufficiently everywhere. Branch lines and dead legs should be kept as short as possible by design, so that product residues and microbial growth are minimised.
Geometry and radii
Internal radii, clean transitions and the absence of sharp edges are important so that product or cleaning media cannot deposit. Horizontal surfaces without drainage should be avoided where possible.
Self-drainage
Pipework and vessels should be executed so that they can drain completely after production or cleaning. Defined gradients and good drainage reduce residual pools and facilitate cleaning.
Connections
Crevice-free, hygienic connections are preferable, for example orbitally welded pipes or hygienic clamp connections. Weld seams must be cleanly executed, tested and documented.
Material and seal selection
Metallic materials must be corrosion-resistant and chemically suitable for the product and the cleaning media. Elastomers and plastics must be suitable for food or pharmaceutical contact and must not release problematic substances under the conditions of use.
Migration behaviour and chemical resistance to cleaning and disinfecting agents and, where applicable, to clean steam must also be taken into account.
CIP and SIP capability
GMP-compliant plants are to be designed so that they can be cleaned and sterilised without dismantling.
CIP
Cleaning in the circuit must wet all internal surfaces reliably and generate sufficiently turbulent flow. Spray balls or spray heads must be arranged so that shadow areas are avoided.
SIP
Sterilisation is typically carried out with saturated clean steam under controlled conditions. Venting, condensate drainage and temperature distribution must be controlled so that no cold spots arise.
Time, temperature, concentration and mechanical action must be defined, controllable and documentable for both processes.
Validatable cleaning
Cleaning is regarded as validatable where planned and documented studies demonstrate that the cleaning procedure reduces residues reproducibly to an acceptable level.
Important requirements are:
- a clearly defined cleaning procedure,
- risk-based limits for residues,
- suitable sampling by swab and rinse samples,
- validated analytical methods such as HPLC, TOC or conductivity,
- worst-case considerations for multi-product plants,
- and repeated successful execution of the cleaning procedure as evidence of reproducibility.
Cleaning and cleaning validation must also be monitored across the life cycle of the plant and reassessed when changes are made.
Avoiding cross-contamination
Cross-contamination is reduced by separating process paths, hygienic valve technology, a design with minimal dead space and validated cleaning procedures. The more sensitive the product and the higher the risk, the more important additional organisational and technical protective measures become.
Qualification, documentation and risk approach
In addition to the design, GMP conformity also includes qualification and documentation. DQ, IQ, OQ and PQ are typical, based on the requirement specification and the functional specification, together with change control, data integrity and a risk-based approach in accordance with quality risk management.
How amixon® supports validatable cleaning and its documentation
A design that makes validation possible
A cleaning validation is only as good as the accessibility of the plant. At amixon®, large Clever-Cut® inspection doors with the OmgaSeal® seal provide complete, ergonomic access to all product-contact surfaces. This is the precondition for swab sampling at worst-case points and for visual inspection.
Because the mixing chamber and mixing tool are welded free of crevices and ground smooth and the mixing tool is supported only at the top, there are structurally no hidden sampling risk points such as gaps, lower shaft passages or dead spaces. Integrated washing lances allow defined, reproducible CIP and WIP cycles; rinse samples can be taken at the dead-space-free outlet. Residual discharge of 99.997 % and better with free-flowing materials markedly lowers the initial soil load of every cleaning cycle.
Qualification in accordance with recognised regulations
amixon® assists on request with DQ, IQ and OQ. Documentation and execution follow, on request, EU GMP and FDA 21 CFR Part 11; integration follows the operator's validation concept from the URS through to commissioning. Every apparatus is a documented one-off from in-house manufacture in Paderborn – material certificates, surface specifications and welding documentation are available without gaps.
Reproducible operation as the basis for validation
Mixing and cleaning programmes can be stored in the PLC; integration into the ERP system is provided for, and a barcode scanner can be integrated for real-time documentation. Cleaning cycles can thus be evidenced batch by batch. Limits, analysis such as swab and rinse tests as well as protein, allergen or conductivity evidence and the acceptance criteria are defined by the operator. amixon® supplies the plant that can be qualified for this purpose and, on request, tests cleaning regimes in advance at the pilot plant with the original product.
Particularly suitable for pharmaceutical applications
For pharmaceutical applications, amixon® supplies the apparatus in GMP-compliant form: usable in FDA-compliant form as sterile mixers and reactors as well as EHEDG- and 3-A-compliant.
An addition for particularly demanding cleaning
At the pilot plant, amixon® can also verify mixing quality and cleanability with the original product under real conditions. This is particularly helpful where the plant has to be designed for products that are difficult to clean, for changing formulations or for high hygiene requirements. Cleaning times, residual discharge and validatability can thus be examined robustly before the investment.
Manufacture in Paderborn as the quality foundation
amixon® develops and manufactures exclusively at the Paderborn works with the greatest depth of manufacture and all components from Germany. As a certified welding company with European, Japanese, Korean and American qualifications, amixon® designs every apparatus as a one-off on the basis of the operator's URS. Quality control remains entirely in-house without gaps, and every specification is verifiable down to component level. This manufacturing autonomy also secures long-term supply: every component can still be re-manufactured reproducibly decades later.