A biotech investor reportedly made $255 million in just 4 weeks on Novavax's 120% surge

• RA Capital Management, a small biotech investment firm, has made $255 million in paper profits in less than four weeks from a bet on Novavax, The Wall Street Journal reported Thursday.
• Shares of pharmaceutical company Novavax have surged nearly 2,300% this year. In February, the company said it was working on a vaccine for COVID-19.
• On Tuesday, shares jumped as much as 41% when the company announced it will receive $1.6 billion from the government to develop and manufacture its coronavirus vaccine.
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For one biotech firm, an investment in vaccine company Novavax is paying off.

RA Capital, a small biotech investment firm based in Boston, made $255 million in paper profits in less than four weeks from an investment in Novavax, Gregory Zuckerman of The Wall Street Journal reported Thursday. The firm bought 4.4 million shares of convertible preferred stock on June 12 for $200 million, about 7.5% of Novavax's total shares, according to the report.

The firm made the investment after becoming convinced that the coronavirus will remain a threat for many years, and that any vaccine may be needed annually, according to the report.

Since June 12, Novavax's shares have skyrocketed 120%. This year, the company's stock has rallied nearly 2,300% amid the coronavirus pandemic — Novavax announced in February it was working on a COVID-19 vaccine.

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It's steadily gained since then as investors look to capitalize on hopes that a vaccine will soon come. On Tuesday, Novavax surged as much as 41% when the company announced it will receive $1.6 billion from the government to develop and manufacture its coronavirus vaccine candidate. It pared some of those gains Thursday, falling as much as 5%.

Shares of competing pharmaceutical companies such as Moderna, Regeneron, and Gilead have also skyrocketed this year.