Why did Moderna start clinical trials on the "Covid 19" vaccine in 2017?

Why did Moderna start clinical trials on the "Covid 19" vaccine in 2017? Well before we even knew about Covid-19 in 2019.

Remember the World Economic Forum and Bill Gates Foundation Covid simulation before the plandemic?

Yes. They knew. It was planned.

Live Simulation Exercise to Prepare Public and Private Leaders for Pandemic Response
https://weforum.org/press/2019/10/live-simulation-exercise-to-prepare-public-and-private-leaders-for-pandemic-response/