Sinovac rockets on strong data for Enterovirus 71 vaccine

Chinese vaccines maker Sinovac Biotech Ltd. (Nasdaq: SVA) saw its shares leap 53% to $4.88 in morning trading on March 14, when the company announced positive preliminary top-line data from its Phase III clinical trial assessing the efficacy, immunogenicity and safety of its proprietary Enterovirus 71 (EV71) vaccine against hand, foot and mouth disease (HFMD).

The primary objective of the study was to evaluate the efficacy of the EV71 vaccine in the prevention of HFMD caused by EV71 in infants of six to 35 months old. The preliminary Phase III data showed that Sinovac's EV71 vaccine was 95.4% (95% CI: 87.5%, 98.3%) efficacious against HFMD caused by EV71.

The Phase III trial showed good immunogenicity and safety for EV71 vaccine. The overall incidence of serious adverse events in this trial was 2.2% among the EV71 candidate vaccine recipients and 2.6% among those receiving a control vaccine during the fourteen months observation period. The difference in rates of serious adverse events is not statistically significant. Most of the SAEs were considered unlikely to be vaccine-related.