Whether you keep up with science and tech-related news on a daily basis, or your consumption post-watching Bill Nye in your 5th grade science classroom has been scarce, you’ve most likely heard about an abundance of COVID-19 related discoveries over the past year. From virus detecting face masks, to biosensors that work like fob cards to electric toothbrush-like vaccine administration devices, it seems the potential treatments and preventative apparatuses just keep coming. Turns out, this wave of new innovations isn’t far from home, as researchers within the Faculty of Engineering at McMaster have created a formulation that can revolutionize vaccine transport and storage; increasing accessibility and reducing waste.
In 2014, Dr. Carlos Filipe, the Chair of the Department of Chemical Engineering at McMaster, and his team of researchers began experimenting with vaccine stabilization. Initially, researchers were trying to detect viruses and pathogens using bioactive paper; similar to detecting the pH of a solution using litmus paper, but they needed a method to avoid virus degradation during trials. Most vaccines require a cold environment ranging between 2–8 °C in order to avoid reducing the efficacy. In the case of COVID-19 vaccines, this is because mRNA is easily destroyed through enzymes, and thus the vaccines must be in an uninterrupted, refrigerated environment from production to dispensation. This need for refrigeration was eliminated through a mixture of two natural compounds, which have unique properties allowing them to accomplish this task, once they are added to the genetic material of the virus (mRNA) and subsequently to the vaccine. The development of thermally stable vaccines can increase availability worldwide, especially in developing countries.
This simple, low cost experiment was tested on two viruses. Both of them were dried with a sugar film made of pullulan: a molecule with good film-forming abilities often used to extend the shelf life of food, and trehalose: a stabilizing agent. Previously, pullulan was used to make water soluble tablets, as it forms an impermeable layer for protection against oxidation of enzymes, after it dries. Similarly, a pullulan-trehalose mixture was dried as a film coating to preserve bacteriophages and maintain their infectivity for up to 3 months.
In order to evaluate their effectiveness as stabilizing agents, the viruses were dried with a combination of both sugars. By measuring the viral infectivity on a target cell (titer) of the sample at different storage times and then comparing it to the initial infectivity prior to drying, it was apparent the mixture of pullulan-trehalose, best maintained its titer, closest to the original state.
The trend was similar all across the board; viruses were able to last at up to 40°C for long periods within the film, with the viral particles trapped within a wall of sugar to avoid any sort of deformations, therefore making them thermally stable.
This discovery led to numerous publications, patents and eventually, in 2019, the creation of Elarex Inc., a startup company whose main objective is reducing the dependency of vaccines on the cold chain and creating equity in vaccine distribution. Carlos Filipe is the co-founder of the company, in addition to being one of the scientific advisors along with Dr. Brian Lichty, an Associate Professor in Molecular Medicine at McMaster’s Immunology Research Centre.
One of the biggest issues within remote areas with low infrastructure and unfavourable terrain, is accessibility and storage of vaccines due to their delicate nature, and many are wasted in the process of delivery. It is easy to assume this would only be an issue for developing countries, however even in the US, the cold chain problem is prevalent in rural communities. Most hospitals in such regions cannot afford the high-end, extremely cold freezers that are necessary for storage of the Pfizer vaccine. Thus, the discovery of this thermally stabilizing mixture and the startup, Elarex, as a whole, would reduce the inequity experienced by these regions which can pave the way for bridging this gap within health systems in general.