The brief

Analyst view

• KOSTAIVE is world's first approved self-amplifying mRNA vaccine.
• Approved in Japan (Nov 2023), EU (Feb 2025) for COVID-19.
• Superior antibody persistence vs. standard mRNA at 12+ months.

Technical approach

As reported

Self-amplifying mRNA

mRNA replication platform

sa-mRNA includes RNA replication genes, allowing self-replication and sustained antigen production in cells.

Lower-dose efficacy

Amplification reduces dose

Self-replication enables smaller vaccine doses with comparable immune responses.

Durable immunity

Sustained antigen expression

Prolonged intracellular antigen production generates durable antibody persistence.