What happened

Shares of Moderna (MRNA 1.58%) climbed 4% on Monday after the biotech announced a major COVID-19 vaccine supply deal. 

So what

Moderna will provide up to 500 million doses of its coronavirus vaccine to Gavi, the Vaccine Alliance. Gavi works with partners -- such as the World Bank, the Bill & Melinda Gates Foundation, and the World Health Organization (WHO) -- to supply low-income countries with much-needed medicines.

Moderna will deliver 34 million doses to Gavi by the fourth quarter. Gavi also has the option to purchase 466 million more doses next year. Moderna will sell the doses at their lowest tiered price. 

A syringe is in a vial next to other vials.

Moderna's new vaccine supply agreement could help to slow the spread of COVID-19. Image source: Getty Images.

The deal comes after the WHO issued an Emergency Use Listing (EUL) for Moderna's vaccine to prevent COVID-19 in people at least 18 years old on Friday. The EUL is similar in some respects to the Emergency Use Authorization (EUA) granted by the U.S. Food and Drug Administration (FDA) to Moderna in December. The EUL helps other countries accelerate their regulatory approval procedures.

"This is an important milestone as we work to ensure that people around the world have access to our COVID-19 vaccine," Moderna CEO Stephane Bancel said in a press release. 

Now what 

Investors can expect to receive an update on Moderna's overall vaccine sales on Thursday. The company is slated to report its first-quarter financial results before the market open.