Vaccines without refrigeration possible, says Cambridge Biostability
eliminating the need for refrigeration has been given UK government
funding in a project to deliver immunisations to the developing
world.
The UK Department for International Development has awarded the company behind the development, Cambridge Biostability, a £950,000 (€1.38bn) grant to bring to production a pentavalent childhood vaccine - i.e. one that guards against five infections in one shot - that can be stored without refrigeration.
Cambridge Biostability's technology is based on anhydrobiosis - a process which enables cells to be preserved in a dehydrated state. It involves embedding vaccine particles in sugar beads - known as sugar glasses - that can be stored without the need for refrigeration; these beads dissolve in the body to release the vaccine when injected.
While common vaccines have been stabilised in sugar glasses before, they have required reconstituting in the field, imparting a degree of uncertainty into the delivery process. Biostability's technology uses a smooth, continuous process of stabilising vaccine molecules in sugar glass - and then suspends these tiny spheres in biocompatible, perfluorocarbon (PFC) liquids. Because the PFC liquids are anhydrous they are inherently bacteriostatic and require no antiseptic additives. The dry spheres suspended in these liquids can also contain many different vaccines with no possibility of chemical interaction between them.
Currently, most vaccines need to be refrigerated to protect them against extremes of temperature that could reduce their potency. This makes it costly to distribute vaccines to those that need them most in the poorer parts of the world. Furthermore, even with refrigeration, many vaccines are damaged in transit.
"By making vaccines stable across a range of temperatures, the new technology removes the need for the cold chain, which currently costs $200 million (€1.58m) a year. It also gives vaccines a very long shelf life, which will save $100 million in wasted vaccines each year," said Cambridge Biostability in a statement.
This means that 10 million extra children could be vaccinated without having to expand budgets, it added.
The new technology also offers the potential of slow release vaccines, which may overcome the need for boosters.
The project is being managed by a public-private partnership involving PATH, the Seattle, US-based Program for Appropriate Technology in Health, and India's Panacea Biotec, which will produce the liquid-stable vaccines.
