Moderna (MRNA) shares slid more than 20% Thursday after the company slashed its sales guidance for 2024, largely because of a lack of new COVID-19 vaccine orders from the European Union.

The company said it now expects total sales between $3 billion and $3.5 billion for the year. That's down from the $4 billion forecast in the first quarter.

The guidance came amid Moderna's second quarter earnings report Thursday. Revenue was $241 million, beating analyst estimates of $131 million for the quarter. But the company missed Wall Street expectations when it reported an earnings loss of $3.33 per share. Analysts predicted a loss of $3.28 per share.

"As you know, the situation in Europe is not good. The growth is low; they still have quite a lot of inflation; there's still a war in Ukraine; and every country is investing more in defense," CEO Stéphane Bancel told Yahoo Finance Thursday.

Another problem is the EU's multiyear contract with competitor Pfizer (PFE), which could satisfy the demand for COVID vaccines and leave Moderna out in the cold. Bancel said he is making the case to European leaders that they should not rely on a single supplier, especially since COVID cases continue to result in more hospitalizations than flu.

"Imagine if something were to happen to a Pfizer factory and being dependent on only one supplier, and they would be in the heart of a (COVID) season ... Imagine the public health catastrophe that this will be," Bancel said.

Bancel added that the EU is also strapped due to increased defense spending and the war in Ukraine. Moderna's struggle is further compounded by waning demand globally.

Some Asian and Latin American countries are also pushing their orders from the end of 2024 to early 2025, weakening Moderna's outlook for the second half of the year.

The company's only chance of recovery is dependent on sales of the new RSV vaccine, which was approved this year and will deploy in the fall for older adults. Moderna is facing fierce competition from GSK (GSK) and Pfizer, which already have RSV vaccines in the marketplace.

Bancel said Moderna has a leg up in the market as the only provider of pre-filled syringes, rather than vials, for both COVID and RSV vaccines. That already helped the Cambridge, Mass.-based company capture 48% of the US market share in 2023 for COVID.

The hit to 2024 revenue comes at a time when the company is in transition. Once only relying on its COVID-19 vaccine business, Moderna is entering a competitive RSV market this fall, as well as awaiting approval of its combination flu and COVID vaccine.

Bancel added he is disappointed in the outlook for the year, and hopes investors understand the longer-term plans.

"This is a speed bump. I'm not pleased about it, obviously. This company, most of the value is in the products that are going to be launching in the next couple of years," Bancel said.

For now, he added, Moderna's story is a "Northern Hemisphere, winter season business."

Anjalee Khemlani is the senior health reporter at Yahoo Finance, covering all things pharma, insurance, care services, digital health, PBMs, and health policy and politics. Follow Anjalee on all social media platforms @AnjKhem.

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