Rapid Sterility Test Systems in the Pharmaceutical Industry: Applying a Structured Approach to Their Evaluation, Validation and Global Implementation.

The current compendial sterility test has a 14-day incubation time and is often the time-limiting step in the Assess and Release Process of pharmaceutical products. There is an ever-increasing number of technologies available on the market that have benefits in addition to faster Time to Result, such as standardization and automation of readout (eliminating analyst subjectivity) and improved data integrity (including eliminating the need for contemporaneous verification of the result by another analyst). Regulators have been encouraging the pharmaceutical industry to adopt these innovative systems; however, it has taken a considerable time before receiving the first approvals from various health authorities (including both the European Medicines Agency and Food and Drug Administration) for the use of an alternative and rapid sterility test for the release of sterile drug product lots. This article describes a systematic 9-step approach to the evaluation, equipment qualification, validation, and deployment of alternative sterility tests that can be applied by pharmaceutical companies wanting to take advantage of the numerous benefits of alternative sterility tests. Two case studies are presented to illustrate the validation and implementation approach, including statistical methods. Although most of the steps toward implementation are aligned, the validation and transfer have been approached differently for each of the case studies because of differences in the chosen technology as well as independent company internal decisions to comply with validation guidelines. However, both case studies show successful implementation of an alternative sterility test for sterile drug products with an ∼50% reduced incubation time.

A Systematic Approach for the Evaluation, Validation, and Implementation of Automated Colony Counting Systems.

For several years, automated colony counting systems have been available with varying degrees of automation. Ever more sophisticated instruments are now increasingly used in microbiological laboratories of pharmaceutical quality control. In addition to the colony counting device, the instruments are now also equipped with robotic systems performing the entire handling of the petri dishes, e.g., automated internal transportation of petri dishes from the incubator chamber to the instrument's enumeration device and back. Moreover, the subjective evaluation of microbial enumeration tests by analysts is replaced with a more accurate and precise process. This leads to significant improvements to data integrity compliance. Automated colony counting systems also often enable cost reduction in the microbiological laboratory, e.g., by not requiring a contemporaneous verification by a second analyst. They also enable direct integration of count data into an existing laboratory information management system, reducing the hands-on time, costs per test and also preventing human errors caused by manual transcription. Altogether, these instruments will lead to improved monitoring and assurance of control of biopharmaceutical processes and manufacturing environments, as well as shortened cycle times in the supply chain. Regulators are encouraging the biopharmaceutical industry to adopt these innovative systems. For example, this year a BioPhorum member company received the first health authority approvals from EU, US, CH, Canada, Australia, and China for the use of automated colony counting systems for in-process bioburden testing and the release of drug substance lots, with an incubation time reduced by about 50%. Although these approvals are for release testing of drug substance lots, the instruments can also be used for environmental monitoring, testing of water samples, etc. This article describes a systematic 9-step approach to the evaluation, equipment qualification, and deployment of automated colony counting systems, which can be applied by biopharmaceutical companies wanting to take advantage of their numerous benefits.

Suppressing posttranslational gluconoylation of heterologous proteins by metabolic engineering of Escherichia coli.

Minimization of chemical modifications during the production of proteins for pharmaceutical and medical applications is of fundamental and practical importance. The gluconoylation of heterologously expressed protein which is observed in Escherichia coli BL21(DE3) constitutes one such undesired posttranslational modification. We postulated that formation of gluconoylated/phosphogluconoylated products of heterologous proteins is caused by the accumulation of 6-phosphogluconolactone due to the absence of phosphogluconolactonase (PGL) in the pentose phosphate pathway. The results obtained demonstrate that overexpression of a heterologous PGL in BL21(DE3) suppresses the formation of the gluconoylated adducts in the therapeutic proteins studied. When this E. coli strain was grown in high-cell-density fed-batch cultures with an extra copy of the pgl gene, we found that the biomass yield and specific productivity of a heterologous 18-kDa protein increased simultaneously by 50 and 60%, respectively. The higher level of PGL expression allowed E. coli strain BL21(DE3) to satisfy the extra demand for precursors, as well as the energy requirements, in order to replicate plasmid DNA and express heterologous genes, as metabolic flux analysis showed by the higher precursor and NADPH fluxes through the oxidative branch of the pentose phosphate shunt. This work shows that E. coli strain BL21(DE3) can be used as a host to produce three different proteins, a heterodimer of liver X receptors, elongin C, and an 18-kDa protein. This is the first report describing a novel and general strategy for suppressing this nonenzymatic modification by metabolic pathway engineering.