Development of a fridge-free thermostabilised tetanus diphtheria (Td) vaccine

Vaccines save ~3 million lives globally each year by preventing many infectious, serious, and potentially deadly diseases including smallpox, polio, measles and diphtheria). Vaccines are normally supplied in liquid form which requires constant refrigeration between 2 to 8°C. According to UNICEF, delivering vaccines using a temperature controlled supply chain (known as cold chain) costs approximately £364 million per year.

Repeated episodes of temperature variation outside of the recommended range can result in an irreversible cumulative loss of vaccine potency. According to WHO, currently approximately half of all vaccines are wasted due to insufficient and suboptimal cold chain capacity. This leads to reduced availability of vaccination which results in ~1.5 million/annum avoidable childhood deaths globally. Furthermore, vaccine wastage costs ~£19 billion/annum of losses to the global economy.

Production of thermostable vaccines represents the optimum solution to the cold chain failure problems. However, there are currently no cost-effective vaccine thermo-stabilisation methods and few thermostable vaccines available. State-of-the-art solutions (HydRIS, Arktek, Arestat and Stabilitech) have disadvantages of high costs related to cold-chain, lower shelf live of less than year and bespoke process-modifications requirements for individual vaccines.

Stablepharma is developing a platform technology 'SPVX02' (novel formulation and lyophilisation process) to stabilise most widely used vaccines at temperatures up to 45degC for 12months. SPVX02 is initially being developed for Tetanus-diphtheria (Td) following WHO guidelines on humanitarian needs with a larger target market (236million doses per annum) and higher value per dose.

Through recently concluded successful Innovate UK funded project (\#52711), Stablepharma has developing a GMP compliant manufacturing process and validated the efficacy of SPVX02 stabilised Td vaccine through pre-clinical trials.

In collaboration with University Hospital of Southampton, this 18months project will further develop SPVX02 to Technology Readiness Level-8 through clinical studies (n=48) and upscale GMP manufacturing process to a capacity of 20,000 vials per batch.