Evaluation of Extreme Depyrogenation Conditions on the Surface Hydrolytic Resistance of Glass Containers for Pharmaceutical Use

This paper is the result of a round-robin activity run by the Technical Committee TC12, Pharma Packaging, of the International Commission on Glass (ICG). The study was motivated by a concern about the risk that the depyrogenation treatment of glass vials, when performed in an abnormal way that deviates from the usual procedure, may have a negative impact on the hydrolytic resistance of the container inner surface after filling with the drug product, for example, by increasing the release of leacheables and/or the propensity to delamination. The study was executed by using 10 mL clear type I borosilicate glass vials representing four different compositions. For the applied depyrogenation process, extreme parameters were chosen with maximum temperature up to 400°C, exposure times up to 72 hours, and different amounts of residual water inside as starting conditions. Those treated samples were tested in seven different laboratories as a round-robin test. A large amount of data was obtained, which clearly indicate that the hydrolytic resistance performance of the Type I borosilicate glass vials is not affected even by such extreme depyrogenation conditions (e.g., 400°C, 72 hours, and not perfectly dried inside). This is an important and useful result, both for glass and pharma companies, based on the 12,000 analytical data collected during the interlaboratory activity.