Moderna (MRNA) stock has been one of 2020’s star performers, up 695%, and judging by its real-world results, many would say justifiably so.

The biggest question for investors, then, is whether those gains are likely to continue. Needham analyst Alan Carr came out with an answer.

The analyst downgraded Moderna shares from Buy to Hold, without suggesting a price target. (To watch Carr’s track record, click here)

Moderna's Covid-19 vaccine candidate mRNA-1273 displayed a 94.1% success rate in preventing the coronavirus in a late-stage study and is currently on the cusp of gaining emergency use authorization (EUA).

The company has an agreement in place with the U.S. government to sell 100 million vaccine doses for $1.225 billion and will receive an EUA bonus of $300 million by January 31, 2021. It also has options for four more 100 million dose deliveries, each worth $1.65 billion.

Carr estimates the company will deliver 200 million doses in the U.S. (initial contract + first option) and an additional 300 million outside the U.S. in 2021.

With so many positive developments, why the change of heart, then? Carr has a simple explanation.

“Moderna has made significant progress in 2020 towards validation of its mRNA platform, particularly through the discovery and development of COVID-19 vaccine mRNA-1273,” the analyst said. “The stock has responded remarkably well and we now believe it is fully valued... The stock may react favorably to EUA issuance, but we do not believe it will justify a meaningfully higher price target. We await competitor vaccine updates and additional data from other Moderna programs, which may support a higher valuation.”

There could be further upside, Carr says, should Moderna “source raw material for production of 1B total doses in 2021.” A further tailwind could be provided by other competitors - AstraZeneca, J&J, Sanofi, and Novavax - should they fail to deliver strong data from their respective late-stage studies. All have said they can exceed the production of 1 billion doses a year.

Overall, most Street analysts also feel Moderna stock has surged enough for now. Going by the $127.69 average price target, the forecast is for an 18% drop in the coming months. (See Moderna stock analysis on TipRanks)

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Disclaimer: The opinions expressed in this article are solely those of the featured analyst. The content is intended to be used for informational purposes only. It is very important to do your own analysis before making any investment.