In vitro diagnostics (IVD) involves testing samples, such as tissue or blood, to detect diseases or other conditions using sensitive tests. IVD can be used to monitor a person’s general health and to aid in the treatment or prevention of diseases.
Most in vitro diagnostic assays are developed based on molecular or immunodetection technologies, including polymerase chain reaction (PCR), enzyme-linked immunosorbent assays (ELISA), chemiluminescent immunoassays (CLIA), lateral flow, cytology, and immunohistochemistry. PCR and its variants are specific and sensitive detection methods used to identify and amplify unique stretches of DNA/RNA indicative of a pathogen or disease state.
In ELISA-based assays, antibodies are attached to a chromogenic enzyme, which in the presence of substrate produces a quantitative, colorimetric signal. In CLIA, an enzyme converts a substrate into a chemiluminescent signal that is emitted as visible or near visible light. The amount of light produced directly correlates to the quantity of target analyte present in the sample. Lateral flow test strips are routinely used to detect certain target components in liquid samples. Based on basic immunochromatography principles, a complex is formed between a detector particle in the sample stream and a capture reagent bound at the test line. Certain staining assays use antibodies and specific stains to identify and localize cells which are indicative of a disease state. These assays are widely used in cytology, hematology, blood typing, and histopathology.
Developing a diagnostic assay from the design stage through product development and final manufacturing employs principles from biology, chemistry, physics and engineering. There is no guarantee that an assay with the required clinical sensitivity and specificity developed within the R&D environment will be transferrable to production scale. An assay that works reliably on the bench top often requires further development and reagent reformulations, when moved to scale-up. Experienced diagnostic assay developers leverage key fit-for-use materials aligned with regulatory requirements and supply-chain security, to save significant time and cost by minimizing variations. The process from the discovery of a promising assay to a marketable IVD kit approved by regulatory authorities may take two years or more to complete.
Upon the successful transition of a diagnostic assay to full-scale production, the developer’s emphasis shifts to monitoring and controlling the quality of components and assembly. Supply chain management becomes critical and risk mitigation strategies are devised to ensure business continuity in the event of manufacturing disruptions. Quality management systems (QMS) and careful documentation of production processes according to ISO and other regulatory guidelines keep the final assay product compliant and sellable. Governing bodies conduct scheduled and unscheduled audits of all IVD manufacturing facilities to verify safety and quality compliance.
IVD manufacturing is a valid strategic decision due to the significant capital expenditure required for in-house manufacturing. In addition to the costs of equipment, there is also the need to develop a Quality Management System (QMS) aligned with all regulatory requirements, the hiring of personnel, and the acquisition of the appropriate certifications. Due to the significant capital expenditure required, many companies choose outsourcing in order to redeploy their capital towards growing their business and developing new products. Considerations for successful assay launch through contract manufacturing include your partnership’s ability to master supply-chain management, assay scale-up to manufacture, and regulatory compliance.