Safety and Immunogenicity from a Phase I Trial of Inactivated Severe Acute Respiratory Syndrome Coronavirus Vaccine

Background: Emergence of severe acute respiratory syndrome (SARS) from the winter of 2002 to the spring of 2003 has caused a serious threat to public health.

Methods: To evaluate the safety and immunogenicity of the inactivated SARS coronavirus (SARS-CoV) vaccine, 36 subjects received two doses of 16 SARS-CoV units (SU) or 32 SU inactivated SARS-CoV vaccine, or placebo control.

Results: On day 42, the seroconversion reached 100% for both vaccine groups. On day 56, 100% of participants in the group receiving 16 SU and 91.1% in the group receiving 32 SU had seroconverted. The geometric mean titre of neutralizing antibody peaked 2 weeks after the second vaccination, but decreased 4 weeks later.

Conclusion: The inactivated vaccine was safe and well tolerated and can elicit SARS-CoV-specific neutralizing antibodies.