In Depth: Why China Still Doesn’t Have an mRNA Shot

As the fast-evolving coronavirus tests scientists’ capacity to develop more-effective vaccines, drugmakers in China are scrambling to catch up with the most advanced technology for producing more powerful shots to better protect the world’s largest population.

Since the pandemic started, China has approved seven home-grown Covid-19 vaccines using four proven technologies to back the country’s vaccination campaign, the world’s largest. But shots based on the new mRNA technology that have been widely used elsewhere are still not available in China. MRNA vaccines, led by products developed by Pfizer-BioNTech and Moderna, have outperformed most other shots in efficacy rates against Covid-19.