Temperature peaks in the manufacturing process are the main cause of delamination in tubular glass vials, which was discovered in a long-term study conducted by Gerresheimer AG and the Alfred University in New York.

The Primary Packaging Glass Division took action directly: the new Gx ARMOR vials are equipped to withstand aggressive active ingredients, reducing the delamination risk.

Experts were surprised by the finding of the long-term study, which confirmed delamination in primary packaging for parenteral solutions is a temperature-induced phenomenon.

It only affects vials made of tubular glass and it is a phenomenon that occurs 98% of the time in the region of the vial base.

Delamination is caused by too high temperatures in the forming process. It can also be exacerbated by the subsequent treatment of the vials with ammonium sulfate.

Gerresheimer and the research team at New York’s Alfred University invested three years in this project. It involved the meticulous testing of 9,000 samples.

The Primary Packaging Glass Division has already responded to the study results with a new product line called Gx ARMOR vials, which are specifically designed for parenteral solutions with aggressive active ingredients and specially equipped to prevent delamination.

Gx ARMOR stands for Gerresheimer Advanced Risk Management and Operational Response. The vials are manufactured in an optimised production process, which limits and continuously adjusts the temperature of the burners.

A camera system monitors the moulding process for every single vial.

Random samples are taken from the production line and tested for their susceptibility to delamination with the new, in-house developed Thermal Hydrolytic Optimisation and Reduction (Gx THOR) control process and the Gx FLASH test procedure.

Gerresheimer Technical Services director Carol Rea Flynn said: "The complex research and development work has paid off.

"We are now launching a brand new generation of optimised vials."


The delamination problem has become worse since the introduction of innovative biotech drugs. Monoclonal antibodies, which are active proteins, cause the glass to flake off the vials’ surface when they are stored for long periods of time, causing corrosion and contamination.

Solutions containing chelating agents or buffer systems, or solutions with a high pH value, can also cause delamination. Although it is such an inert material, Type I borosilicate glass is affected by the phenomenon.

In the US, in particular, delamination has resulted in many product recall campaigns, generating significant losses in the pharmaceutical industry.