Moderna (MRNA) was on track to see a weekly gain of 21% as of Wednesday. Shares of the vaccine maker rose 11.7% the prior day following the first reported bird flu death in the US.

The stock was up as much as 1% in premarket trading Wednesday.

Moderna in July 2024 was awarded $176 million from the US government to advance the development of its mRNA H5N1 (bird flu) vaccine, which is in early stages of testing. The award came after an outbreak of the virus in cows infected three dairy workers, prompting concerns of an outbreak in humans.

As of January, there have been 66 confirmed cases of H5N1 in the US since 2024, the CDC said Monday.

“CDC has carefully studied the available information about the person who died in Louisiana and continues to assess that the risk to the general public remains low,” the federal public health agency said. “However, people with job-related or recreational exposures to infected birds or other animals are at greater risk of infection.”

After Moderna’s development of a Covid-19 vaccine fueled a massive surge in revenue — rising more than 2,000% in 2021 from the prior year, with the vaccine maker turning its first-ever profit — the company has sputtered in a post-pandemic world. Moderna’s revenue fell 64% to just below $7 billion in 2023 (far below the $18.5 billion in sales reported in 2020), and the company reported a loss of roughly $12 per share.

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Wall Street analysts tracked by Bloomberg expect the company to report a loss of a little over $9 per share for the fiscal year 2024 and for sales to halve from the prior year.

Even with this week’s rally, Moderna shares are down nearly 60% from last year. More than half of analysts tracked by Yahoo Finance have a Hold rating on the stock but on average see shares rising to $74 over the next 12 months, implying a 56% gain from their current level.

Other companies developing an mRNA bird flu shot also rose on news of the bird flu death. Novavax (NVAX) surged nearly 11% Tuesday. German biotech firm CureVac (CVAC) rose more than 4%. 

CureVac is developing an mRNA bird flu shot in collaboration with Indian pharma giant GlaxoSmithKline (GSK) (GLAXO.BO). Pfizer (PFE) ticked up a much more modest 0.9%, while GSK itself dropped 1%.

An uptick in COVID-19 cases reported by the CDC also helped prop up vaccine makers earlier this week.

Laura Bratton is a reporter for Yahoo Finance. Follow her on Bluesky @laurabratton.bsky.social. Email her at laura.bratton@yahooinc.com.

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