IN-006

Primary objectives: 1) To evaluate the safety and reactogenicity of IN006 in healthy subjects aged 18-59 years; 2) To evaluate the safety and reactogenicity of IN006 in healthy subjects aged 60 years and above after initial vaccination. Secondary objectives: 1) To evaluate the humoral immune response and its persistence after IN006 vaccination in healthy subjects aged 18-59 years; 2) To evaluate the cellular immune response and its persistence after IN006 vaccination in healthy subjects aged 18-59 years; 3) To evaluate the safety and reactogenicity of revaccination of IN006 12 months after initial vaccination in healthy subjects aged 60 years and above; 4) To evaluate the humoral immune response and its persistence after initial vaccination of IN006 in healthy subjects aged 60 years and above; 5) To evaluate the cellular immune response and its persistence after initial vaccination of IN006 in healthy subjects aged 60 years and above.