Not a huge surprise given the absolute face ripping jump MRNA had when the vaccine was first announced. The ~$20B company jumped 174% overnight, and then climbed another 70% over the last two months, now only dropping 18% on this news.

To illustrate how much they've gone up, this 18% drop is just slightly less than their entire market cap in June (four months ago)

The usual “buy the rumour, sell the news” then?

When it clicked that you meant MRNA the ticker symbol, it also just clicked for me that the name Moderna is a play on mRNA. Not sure why I never noticed that before.

Like the FedEx logotype arrow, now I will never unsee it.