Critical studies on the novel development and implementation of vaporized hydrogen peroxide (VH202) for terminal sterilization of medical devices encompassing use of flow cytometry for the real-time commensurate monitoring of microbial inactivation

Abstract

Aims and Rationale: Sterilization microbiology relies on determining the linearity of microbial survivor curves for calculating decimal reduction times (D-values) that is used to inform sterility assurance levels (SAL), critical to efficacious sterilization of medical device for patient care application. Medical devices play an important role in the provision of healthcare, with a global market estimated at $432bn and expected to surpass $650bn by 2028. Terminal sterilization of medical devices is currently provided by established methods including Gamma, E-beam and X-ray radiation with Ethylene Oxide gas sterilization continuing to be the method of choice due to wide ranging material compatibility. Given the hazards associated with EO gas, alternative methods are actively being pursued by the global medical device industry. Furthermore, there is an increasing opportunity to develop sustainable sterilization microbiology processes necessary to meet emerging needs including evolution of device features containing heat sensitive polymers, inclusion of sensor technology and biologics. This constitutes the first, and timely study to (i) establish and alternative method using vaporized hydrogen peroxide (VH2O2) at an industrial sterilization scale and (ii) report on the linearity of microbial inactivation plots for treated Geobacillus stearothermophilus and Bacillus atrophaeus spores to demonstrate the appropriateness of process validation as a means of confidently determining SAL.