Tempris – Temperature Measurement in Lyophilization

Vaccines becomes an important part of public health. They play an essential role in preventing the spread of infectious diseases and have saved millions of lives worldwide. Most of vaccines, however, are very sensitive to temperature and need to be lyophilized to remain effective. Pfizer is one of the largest vaccine manufacturers of the world.

In order to develop a robust manufacturing process significant efforts need to be made to ensure the quality of the product. We typically design lyophilization process in such way that even relatively wide variability of process parameters during manufacturing do not impact vaccine quality. We perform robust experiments at laboratory scale generating a wide product temperature design space (and wide range of process parameters associated with it) which produce product with acceptable quality. We also make sure that product quality attributes remain within specification for a desired shelf life for all samples generated during robustness study.

When we transfer lyophilization process we are making sure that product temperature at large scale remains within product design space generated during robustness study. This guarantees that stability profile of commercial material would be similar to that in laboratory study. Measurement of product temperature in laboratory dryer is easy and routine task. It is very difficult, however, to measure product temperature on the commercial scale dryer, especially, when it is equipped with automated vial loading system (ALUS).

Tempris, wireless sensor, allows placement of temperature sensors in any location within freeze-dryer. It is also a sensor of choice if product temperature of edge vials is monitored. Tempris sensor is not releasing heat while wired temperature sensors (thermocouples or data loggers) can transfer some heat into the product (very notable for the edge vials), obscuring the actual product temperature. It is especially very important if small fill volume is used when readings of thermocouples and data loggers from the edge vials produce uncertain temperature profiles.

Recently, we performed large scale experiments for one of our vaccine candidates using Tempris to ensure robustness of our process at scale. We demonstrated that product temperature profiles for both edge and center vials remain within design space, confirmed during laboratory robustness study. This provides insurance that commercial process will produce a product with the desired quality and provides strong support for our regulatory application.