Avecia spoilt for vaccine formulation choice
British biotechnology firm Avecia has put together a consortium of
four companies to develop a version of its anthrax vaccine with
increased stability so it works without the need for the
conventional cold chain.
The research, which could have technological benefits for the wider vaccine manufacturing sector, is driven by fears in the US of a terrorist attack with anthrax on civilian population.
The most important of these benefits would be improved temperature stability, which would simplify storage and transport and prolong shelf life, thereby also reducing the overall cost of large scale vaccine provision.
Avecia's vaccine, currently in Phase II clinical trials, is called Thraxine and is based on a recombinant Protective Antigen (rPA) obtained from the non-disease causing strain of B. anthracis, the bacterium that causes anthrax, using recombinant DNA technology.
To establish which formulation of Thraxine can be stored, transported and used most effectively, Avecia has contracted four UK firms - Lyosolutions, Cambridge Biostability, Defence Science and Technology Laboratories (Dstl) and XstalBio - to develop versions of the vaccine using their technologies.
Lyosolutions will use freeze drying (lypophilisation), the most established method to immobilise solution components and reduce thermal inactivation.
"Freeze drying is a well established technique, there are other technologies that are very promising but may take a lot of time to take into good manufacturing practice (GMP) manufacturing," Gerald Adams, president of Lyosolutions, told In-PharmaTechnologist.com.
"However, freeze drying is a relatively expensive technique which takes a long time to complete, so it will be useful to evaluate it against the other more modern methods."
Cambridge Biostability will work with a smooth continuous process of drying vaccine molecules in mixed soluble glass to create tiny stable glass spheres which are then suspended in a non-aqueous liquid, never dissolving and remaining physically stable for years until injected into the body.
Dstl will deploy microencapsulation, which involves protecting the vaccine with a thin layer of biodegradable substance referred to as a microsphere.
XstalBio, on the other hand, will use its protein-coated microcrystals (PCMC) to try to increase stability and bioactivity and lower aggregation under temperature and humidity stress conditions.
"After the different vaccines have been developed we will select the most stable and start a pilot-scale production of around 1,000 doses," Avecia spokeswoman Bridget Hall told In-PharmaTechnologist.com.
"We believe Avecia was selected by the National Institute of Allergy and Infectious Diseases (NIAID) because of the good progress it has made in second generation vaccines and its competitive involvement."
The latest NIAID award follows a $71m contract awarded to Avecia in September 2003 for ongoing development of rPA vaccine.
What is more, Avecia and Dstl are also collaborating, under a $50m contract awarded to Avecia in October 2004, on the development of a new plague vaccine for NIAID, using similar protein-based technology to rPA.
