The two investors each contributed $7.5 million in the form of a convertible loan that bears interest, or, at the investor's election, converts into 7.5% of the total equity interest of Sinovac R&D.

The vaccine, dubbed CoronaVac, was shown in preclinical results to be safe and provides protection to rhesus macaque monkeys through an animal challenge study.

Governmental authorities granted Sinovac approval to conduct both phase I and phase II human clinical trials in China. The phase I clinical trial, which started in April, evaluated the safety, tolerance, and preliminary immunogenicity of CoronaVac. In May, the phase II trial started and evaluates the immunogenicity and safety of CoronaVac in a larger population in order to define the dosage, regimen, and immunization schedule.

The firm is building a commercial vaccine production plant that is expected to manufacture up to 100 million doses of CoronaVac annually.