Long-term Thermostabilization of Live Poxviral and Adenoviral Vaccine Vectors
Vaccines based on live viruses must remain infectious to be effective, therefore requiring a need for continuous refrigeration to maintain stability and viability.
Vaccines based on live viruses must remain infectious to be effective, therefore requiring a need for continuous refrigeration to maintain stability and viability. A requirement that can be costly and difficult, especially in developing countries. Scientists at Oxford University and Nova Bio-Pharma Technologies have developed a proof of concept study that could offer an affordable way of making vaccines stable at room temperature, including elevated temperatures experienced in tropical settings. This would remove the need for fridges, freezers, refrigerated trucks and shipping containers and the infrastructure needed to maintain the cold chain from point of manufacture to point of use. Preparing vaccines that do not need refrigeration has been identified as one of the major unsolved problems in global health.
Using pox and adeno virus the team involved in this study showed that their method made it possible to store two different virus-based vaccines for up to six months at 45°C without any degradation and up to a year at 37°C with minimal losses. This was achieved by mixing the vaccine with the sugars trehalose and sucrose and allowing the mixture to dry out on a simple filter or membrane preserving the vaccine in suspended animation, which is then easily rehydrated with water. This membrane can easily be incorporated into a holder attached to a syringe for almost simultaneous reconstitution and injection at point of use.
