Clinical trials to develop a subunit vaccine for contagious bovine pleuropneumonia in Kenya

Contagious bovine pleuropneumonia (CBPP) is a significant disease among cattle in sub-Saharan Africa, causing losses estimated at US$48.6 million annually. A commercially available live attenuated vaccine for CBPP exists, but it does not provide long-lasting immunity, it causes adverse side effects, and it requires cold chain management to maintain efficacy, which makes it challenging to deliver to smallholder livestock farmers.

As part of the Canadian International Food Security Research Fund, IDRC and Global Affairs Canada funded the development of a novel CBPP vaccine using reverse vaccinology. Preliminary studies were promising and suggested that the recombinant subunit vaccine could be more effective and safer than the current vaccine. However, the research team has yet to provide sufficient information on the protective capacity of the vaccine, largely due to the inability to reproduce the disease experimentally. This technical drawback has withheld a final verdict on whether the new recombinant vaccine is viable and effective to replace the current CBPP vaccine.

The objective of this project is to achieve robust experimental evidence that the protective efficacy of the recombinant subunit vaccine is greater than the live attenuated CBPP vaccine. The project will establish and use a novel experimental infection model to demonstrate proof of concept that meets scientific and statistical thresholds, which could also provide justification for further development and commercialization activities for the vaccine.