Recombinant Yersinia Pestis (rYP)

Avecia is involved in the development of a new type of plague vaccine called rYP – recombinant Yersinia Pestis, which is the scientific name for the plague bacterium. The technology for the vaccine was initially developed in the UK by the Defence Science & Technology Laboratory (Dstl), part of the UK Ministry of Defence.

The process development and scale-up technologies have since been progressed jointly by Dstl and Avecia, using Avecia’s fermentation expertise and manufacturing capabilities.

In October 2004, Avecia was awarded a US$50m contract for the development of the new vaccine by the US National Institute of Allergy and Infectious Diseases (NIAID), which is ultimately an agency of the US Department of Health & Human Services (DHHS).

The contract calls for the production of trial quantities of the new vaccine, which is designed to create an immune response to inhalational or pneumonic plague which in turn is designed to protect the recipient against subsequent risk of infection in the event of exposure to the bacteria. Protocols for further, Phase II, human clinical trials - to determine the optimum dosing regime – are currently being progressed.

Avecia’s vaccine consists of two recombinant antigens (rF1 and rV), produced in Escherichia coli. The rF1 antigen is a capsular protein and the rV antigen is a secreted protein. The target indication for the vaccine is the prevention of the bubonic and pneumonic forms of the disease in healthy adult populations. In a military or bioterrorism context it is the latter indication which presents the greatest threat.