Sinovac shares soar on success of PhIII EV71 vaccine in China

Shares of Beijing-based Sinovac Biotech ($SVA) soared 30% this morning after investigators reported promising Phase III data on its EV71 vaccine, designed to protect infants from hand, foot and mouth disease. But an analyst tells reporters that the party may be premature if competing vaccines now in development prove effective in ongoing late-stage trials.

The biotech says that the Phase III study demonstrated a 95.4% efficacy rate with no significant difference in the rate of severe adverse events when compared with a control-arm vaccine. A total of 10,000 infants were recruited in three Chinese provinces in the months ahead of the hand, foot and mouth disease season. 

"The conclusion of this trial marks an important milestone in the development of our proprietary vaccine," said Sinovac CEO Weidong Yin in a release. "Hand, foot, and mouth disease continues to represent a significant unmet public health need and economic burden in China, as well as several other Asian countries. Our EV71 vaccine is poised to provide an effective solution to prevent hand, food and mouth disease caused by EV71, a much needed resource given the current limited prevention and EV71 specific treatment methods."

Not so fast, Aegis Capital analyst Raghuram Selvaraju tells Reuters. China National Biotec Group and Kunming Institute of Biological Products are expected to report their own data in coming months. And comparable results would likely lead to a market showdown, with rivals splitting the revenue available.

"If those programs show efficacy rates of greater than 90 percent, then Sinovac has got a problem," Selvaraju told Reuters. "If their efficacy rates are below 70 percent, Sinovac will be the dominant leader in the market."

- here's the press release
- read the Reuters story