Canada's Medicago reports positive early data for H7N9 vaccine

Global concern is growing over the outbreak of H7N9 avian influenza in China. So far, 133 cases of H7N9 sickness have been confirmed, and at least 37 deaths are thought to have been caused by the disease.

There is limited knowledge on the scope, cause and source of the disease, and it's not yet known whether it can be transmitted among people. The potential for the virus to mutate into one that's fully transmissible to humans and morph into a serious pandemic has scientists and government officials scrambling to find a way to thwart the disease. One Canadian vaccine maker's H7N9 treatment could be the answer.

Quebec-based Medicago unveiled new positive interim results from a preclinical trial for an H7N9 avian influenza vaccine candidate made from vaccine-like, plant-based particles. When injected in mice, three micrograms of the H7 vaccine increased the level of antibodies needed to ward off disease after one dose.

Scientists have predicted low immunogenicity for potential H7 vaccines--that is, new vaccines are likely to be limited in their ability to provoke an immune response in humans.

"However, our results indicate that our plant-based H7 vaccine is able to generate a high immune response in animal models," said Andy Sheldon, president and CEO of Medicago.

Most human cases of H7N9 have reported a history of exposure to animals, mostly chickens, but studies have shown that the disease can pass between ferrets under certain conditions. While cases have been reported in both men and women across a wide age range, the majority of cases have occurred in middle-aged or older men.

What makes H7N9 tricky to track is that unlike H5N1 viruses, the H7N9 virus does not kill bird populations, which limits the ability to control the source of infection.

Durham, NC-based BioCryst ($BCRX) is also working on a vaccine against the deadly influenza virus. The government-funded company won a surprise approval last month from Chinese regulators for its flu treatment peramivir, which failed to meet endpoints in a 2012 Phase III trial. Peramivir is intended as an intravenous flu treatment for hospitalized patients.

- here's the press release