Pharmaceutical Technology-05-01-2007

Irradiation is an established method of sterilization for pharmaceutical products. Radiation sterilization can be achieved with gamma rays, electron beams, and X-rays. Each of these techniques has its advantages and disadvantages. The author describes these methods, the ways to find the correct sterilization doses, and the regulatory and safety concerns about irradation sterilization.

Validating the sterilization process is extremely important in pharmaceutical manufacturing. The authors explore different types of sterilization processes and discuss the importance of finding the worst-case positions of loads or equipment to be sterilized and the worst-case conditions for each sterilization cycle. Biological indicators (BIs) can be used to simulate worst-case scenarios and determine the effectiveness of a particular sterilization process.

Pre-use integrity testing of sterilizing-grade filters eliminates the potential adverse effects of filter loading on the integrity-test results, allowing unambiguous correlation with the integrity-test specification established during filter-validation studies.

A biological indicator (BI) measures the effectiveness of the sterilization process to which it is subjected. Factors such as the test organism, the packaging, the culture material, and the test system all influence a BI's resistance. Carrier material is an often-overlooked factor that also influences BI resistance. The authors examine various solid and liquid carriers, describe their properties, and investigate how they influence BI resistance.

The author clarifies the definition and objectives of overkill sterilization for steam sterilization cycles. Current sterilization practices are reviewed and the validation difficulties associated with the various definitions of overkill sterilization are explored.

Aseptic processing has advanced over the past several decades, yet the pharmaceutical industry is still accepting of its limitations, particularly as it relates to human intervention as a source of contamination. The authors explain the importance of further diminishing the role of operators in aseptic processing and the approaches and technologies needed to achieve that goal.