Singapore: Sinovac Biotech, a provider of vaccines in China, reported preliminary top-line data from its phase III clinical trial assessing the efficacy, immunogenicity and safety of the company's proprietary Enterovirus 71 (EV71) vaccine against hand, foot and mouth disease.

The primary objective of the study was to evaluate the efficacy of the EV71 vaccine in the prevention of hand, foot and mouth disease 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 percent efficacious against the disease.

The phase III trial showed good immunogenicity and safety for Sinovac's EV71 vaccine. The overall incidence of serious adverse events in this trial was 2.2 percent among the EV71 candidate vaccine recipients and 2.6 percent 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 them were considered unlikely to be vaccine-related.

The double-blinded, randomized, placebo controlled phase III clinical trial was conducted at three sites across China's Jiangsu province. Approximately 10,000 healthy infants completed the two dose vaccination schedule (at 0 and 28 days) in the first quarter of 2012, prior to the hand, foot and mouth disease epidemic season in China, followed by active monitoring period.

In parallel, Sinovac conducted another clinical study that was comprised 1,400 volunteers and designed to evaluate the consistency of three consecutive lots of EV71 vaccine manufactured by the company. The study results showed consistent immune response for all three lots and a good safety profile. With immunogenicity equivalent across the three consecutive lots, the results showed Sinovac's vaccine production process and quality are stable.