Sinovac Biotech Ltd. ("Sinovac" or the "Company"), a leading provider of biopharmaceutical products in China, announced that the inactivated COVID-19 vaccine candidate developed by Sinovac Life Sciences (Sinovac LS), or "CoronaVac," shows good safety and immunogenicity on healthy adults aged 60 and above from its phase I/II clinical studies conducted in China, which is comparable to the result in healthy adults aged from 18 to 59 in the earlier studies.

The phase I/II clinical trial on elderly volunteers were randomized, double-blinded and placebo controlled trials with two-dose immunization scheduled at 28 day intervals.

CoronaVac was tested on a total of 421 healthy adults aged between 60 to 89 years old in the phase I/II clinical trial. The vaccine candidate appeared to be well tolerated for low dose, medium dose, and high dose groups. No vaccine-related serious adverse event was reported. Both the seroconversion rate and GMT level for elderly volunteers were comparable to the adult group aged 18 to 59 years old. According to the results, the medium dose was selected to enter into phase III trial. The seroconversion rate and GMT for the medium dose group was 98.0% and 42.2 in elderly volunteers, respectively; and 97.4% and 44.1 in healthy adults. The detailed data will be published in a peer reviewed journal.

Mr. Weidong Yin, Chairman, President and CEO of Sinovac, commented, "I am very pleased that our vaccine candidate shows promising results, especially on elderly volunteers who are a highly vulnerable group impacted by the COVID-19 pandemic. As Sinovac is accelerating its vaccine development against the fast spread of the virus, we have completed the construction of our production facility and have commenced production of CoronaVac. Sinovac remains committed to the development of vaccines to fight against the coronavirus."