Coming into 2020, Moderna (NASDAQ:MRNA) was a $6.5 billion biotech

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with the goal of using messenger RNA (mRNA) -- the molecule that tells cells what proteins to make -- to fight and prevent disease. Not much was known about the company's technology or even the diseases its drugs would target, but that changed in 2020 as the company became one of the leaders in the fight against COVID-19. 

A table of COVID-19 vaccine vials with an ascending trend line superimposed over the vials.

Image source: Getty Images.

A breakout year

Moderna's stock rose 434% during 2020,

https://ycharts.com/companies/MRNA">MRNA data by https://ycharts.com">YCharts

but that number doesn't capture how eventful the year was, or the ups and downs shareholders experienced. After receiving funding from the Coalition for Epidemic Preparedness Innovations in late January, the company worked with the National Institute of Allergy and Infectious Diseases to deliver a COVID-19 vaccine candidate a month later.

Positive phase 1 data were released in mid-May, and management promptly raised $1.34 billion through a secondary share offering. On Nov. 30, the company provided analysis from phase 3 data showing its vaccine was 94.1% effective at preventing COVID-19. Three weeks later, on Dec. 18, the Food and Drug Administration (FDA) granted emergency use authorization (EUA). 

Although the stock's rise has been tremendous, its overall uneven progress offers a lesson in perseverance for shareholders. While everyone would welcome a more than 400% rise in a stock, holders had to endure a 25% sell-off (or more) four different times.

MRNA Chart

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Looking ahead, the company is well positioned for the future. Moderna had $3.3 billion in cash and investments on its balance sheet as of Sept. 30 and recently increased the number of COVID-19 vaccine doses it expects to make in 2021 from 500 million to 600 million. The company has already supplied 18 million of an agreed-upon 200 million doses to the U.S. government and has additional deals with Canada, Israel, South Korea, and the European Commission, among other recipients . Despite this good news already priced into shares, the company has said it could produce as many as a billion doses this year. If so, last year's gains in the share price could continue through 2021.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.