In March, while testing bioREV as a means of dehydrating the a salmonella typhoid (Ty21a) vaccine, EnWave’s development partner Aridis discovered that the residual moisture levels achieved were between 5 and 6 per cent, outside industry acceptable limits.
Based on the initial data, EnWave invested an additional C$120,000 (€78,684) in the project, resulting in the development of freezeREV technology. The firm claims that dehydration levels produced with the new kit can help drugmakers significantly cut energy, processing and shipping costs.
The water content of vaccine products has a dramatic affect on their durability and the way in which they can be stored. In general, the more dehydrated a vaccine the longer it can be stored at room temperature without losing therapeutic efficacy.
At present, lyophilisation is the “gold standard” method for drying vaccines and liquid pharmaceuticals. But the process is expensive and can often result in a significant loss of biological activity because it can induce structural changes in components of the product in question.
The overall aim of projects like EnWave's is to make vaccines with improved shelf-life and stability that can be shipped and stored in ambient conditions, as this will reduce production costs, lower prices and improve their stockpiling potential.
Microwave-assisted dehydration
One of the key features of EnWave’s technology is its incorporation of microwave-assisted freeze drying. Previous attempts to use microwaves in freeze drying have resulted in uncontrolled electrical discharge, or "arcing", causing equipment and product damage, along with uneven drying rates.
EnWave's platform is designed to eliminate both of these problems and offer dramatically reduced processing times compared with lyophilisation, which can take days to prepare a single vaccine batch.
Company CEO John McNicol explained that: "One of the advantages of freezeREV technology is that it is more compatible with freeze drying technology that is used by the industry today."
"We are now evaluating commercial designs for a high-speed freezeREV vacuum microwave dehydrator capable of replacing a conventional freeze dryer with seamless integration into an existing plant configuration," he added.
EnWave’s next step is to conduct trials on a number of vaccine products to improve both the freezeREV system’s process consistency and the long-term shelf life of medications to which it is applied.
The company is also searching for a partner with lyophilisation manufacturing experience to support the commercial design and scale-up of the freezeREV equipment.