BioWorld International Correspondent

LONDON - Microscience Ltd has signed a collaborative deal with Merial Animal Health to use its functional genomics platform to develop two avian vaccines.

The financial terms were not disclosed, but the deal includes up-front fees and milestone and royalty payments. Douglas Thomson, director of business development, told BioWorld International, "The deal is significant in financial terms, and is an important validation of our technology."

The first project aims to develop a vaccine against Salmonella enterica in poultry. "This is not a serious disease in poultry, but it is in humans. The aim is to eliminate salmonella from the food chain," he said. This will allow producers to guarantee their chicken is salmonella-free, and thus command a higher price. Eggs with a salmonella-free guarantee were recently introduced in the UK and now have the largest market share, despite premium pricing.

The second project will develop a vaccine against Pasteurella multocida, an economically significant pathogen that affects avian species, and in particular turkeys.

Thomson said work on the two pathogens is quite well advanced and he believes commercial products could be available in two to three years. Microscience will apply its Signature Tagged Mutagenesis (STM) platform, which makes it possible to rapidly identify virulence genes in pathogens. Unlike expression-based methods for doing this, STM identifies genes required for survival and growth in the host directly, often assigning a function to the identified gene in the process.

Microscience, based in Wokingham, Berkshire, is applying STM in house to the development of human vaccines. Its lead product is a live, attenuated typhoid vaccine, currently in Phase I. It is orally administered and requires only one dose, as opposed to existing products, which are four-dose oral, or administered by injection. Two other vaccines, against neonatal Group B Streptococcus, the leading cause of neonatal mortality in North America and Europe, and Meningitis B, are in preclinical development.

The company says that STM also opens the way to a new class of small-molecule antimicrobials. Because STM identifies genes that are essential for survival in the host but not in the environment, small molecules against these targets would only kill pathogens while they are causing disease. This could have the important effect of reducing selection pressure for the development of resistance to the drugs.

The deal with Merial is Microscience's first collaboration on animal vaccines, and Thomson hopes that if the first two projects are successful it will lead to an ongoing strategic partnership with the world's largest animal health company.

Merial, headquartered in London, was formed in 1997 by the merger of the animal health divisions of Rhone-Poulenc and Merck & Co.