Implications for the pharmaceutical industry
Initially, the concern over glass flakes focused on product quality and patient safety. Recent data have shown, however, that
foreign particulate matter such as glass flakes can serve as nucleation sites for protein and peptide fragment aggregation
(16–19). Such aggregates have been shown to generate immunological effects and can render biopharmaceuticals ineffective,
thus causing considerable risk to the patient (20).
Glass compatibility with pharmaceutical liquids is an ongoing industry challenge. The phenomenon is well described and understood
in the literature. Existing analytical techniques can evaluate the suitability of glass packaging for parenteral liquids.
These tests should be employed to detect potential problems. Visual inspection continues to be the standard method for detecting
glass flakes, but it is a lagging indicator, not a leading one.
The author would like to recognize the efforts of the following people who have contributed to this investigation: Nick Toltl,
research and development manager at SGS Canada; and Alan Shi, engineer at Medtronix. The author also would like to thank the
following current and former employees of Eli Lilly and Company: Matthew Allgeier, research scientist of pharmaceutical sciences
R&D; Xia Dong, principal research scientist for analytical sciences R&D; Michael Foubert, associate consultant chemist of
analytical sciences R&D; Bethany Bustard, consultant chemist of manufacturing sciences and technology; Sheryl Peoples (retired);
Jeffrey Hoefer, director of statistics, manufacturing science, and technology; David Crozier, retired; Nathan Milton, research
advisor for pharmaceutical sciences R&D; and Tim Shelbourne, research scientist in analytical sciences R&D. This work could
not have been accomplished without the support of the management of Analytical Sciences Research and Development in Eli Lilly
Ronald G. Iacocca is a senior research advisor in analytical sciences R&D at Lilly Research Laboratories, Eli Lilly and Company, Indianapolis,
IN 46285, firstname.lastname@example.org