Novavax (NASDAQ:NVAX) started off 2020 as a micro-cap. It was trading at $4 a share, and its market capitalization was barely over $100 million. The stock had dropped all the way down to penny-stock land. The biotech had no profits and no FDA-approved drugs. Most investors had given up on the stock. But there were reasons to be bullish.

This tiny company had arguably the best flu vaccine in the world, NanoFlu. The drug was in the middle of phase 3 trials, and it had won all its head-to-head competitions against the market-leading flu vaccines from Sanofi (NASDAQ:SNY). In March, when Novavax reported positive news in its phase 3 trial for NanoFlu, the stock jumped up to $14 a share.

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This was a nice three-bagger in two months. What made this run even more magnificent was the rest of the stock market was in freefall because of the coronavirus. Not surprisingly, Novavax had already announced that it was pursuing a COVID-19 vaccine. And the stock market loved this news.

The stock jumped dramatically in May, when the Coalition for Epidemic Preparedness Innovations (CEPI) invested $384 million in Novavax's vaccine candidate for COVID-19. This was a huge validation of Novavax's science and sent the stock skyrocketing to $40 a share. In July, Novavax was awarded $1.6 billion by Operation Warp Speed to help pay for its COVID-19 vaccine. That news sent the stock over $100. And then positive data from the phase 1 trial sent the stock up over $180 a share. And that's how your stock goes up 4,000%.